0.6.3 release

docs(all): Add complete documentation information to README

.appveyor.yml

@@ -1,23 +1,24 @@
 environment:
-    CARGO_TARGET: x86_64-pc-windows-gnu
-    matrix:
-        - TARGET: x86_64-pc-windows-msvc
-        - TARGET: i686-pc-windows-gnu
+  OPENSSL_INCLUDE_DIR: C:\OpenSSL\include
+  OPENSSL_LIB_DIR: C:\OpenSSL\lib
+  OPENSSL_LIBS: ssleay32:libeay32
+  matrix:
+  - TARGET: i686-pc-windows-gnu
+    BITS: 32
+#  - TARGET: x86_64-pc-windows-msvc
+#    BITS: 64
+
 install:
-    - ps: Start-FileDownload "https://static.rust-lang.org/dist/rustc-nightly-${env:TARGET}.tar.gz"
-    - ps: Start-FileDownload "https://static.rust-lang.org/cargo-dist/cargo-nightly-${env:CARGO_TARGET}.tar.gz"
-    - 7z x rustc-nightly-%TARGET%.tar.gz > nul
-    - 7z x rustc-nightly-%TARGET%.tar > nul
-    - 7z x cargo-nightly-%CARGO_TARGET%.tar.gz > nul
-    - 7z x cargo-nightly-%CARGO_TARGET%.tar > nul
-    - call "C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC\vcvarsall.bat" amd64
-    - set PATH=%PATH%;%cd%/rustc-nightly-%TARGET%/rustc/bin
-    - set PATH=%PATH%;%cd%/cargo-nightly-%CARGO_TARGET%/cargo/bin
-    - SET PATH=%PATH%;C:\MinGW\bin
-    - rustc -V
-    - cargo -V
+  - ps: Start-FileDownload "http://slproweb.com/download/Win${env:BITS}OpenSSL-1_0_2g.exe"
+  - Win%BITS%OpenSSL-1_0_2g.exe /SILENT /VERYSILENT /SP- /DIR="C:\OpenSSL"
+  - ps: Start-FileDownload "https://static.rust-lang.org/dist/rust-beta-${env:TARGET}.exe"
+  - rust-beta-%TARGET%.exe /VERYSILENT /NORESTART /DIR="C:\Program Files (x86)\Rust"
+  - SET PATH=%PATH%;C:\Program Files (x86)\Rust\bin
+  - SET PATH=%PATH%;C:\MinGW\bin
+  - rustc -V
+  - cargo -V
 
 build: false
 
 test_script:
-    - cargo test --verbose --no-default-features
+  - cargo build --verbose

.travis.yml

@@ -1,20 +1,49 @@
 language: rust
-sudo: required
 
 rust:
-  - stable
-  - beta
-  - nightly
+- stable
+- beta
+- nightly
+
+matrix:
+  allow_failures:
+    - rust: nightly
+
+sudo: false
+
+cache:
+  apt: true
+  pip: true
+  directories:
+  - target/debug/deps
+  - target/debug/build
+  - target/release/deps
+  - target/release/build
+
+install:
+- pip install 'travis-cargo<0.2' --user
+- export PATH=$HOME/.local/bin:$PATH
+
+addons:
+  apt:
+    packages:
+    - postfix
+    - libcurl4-openssl-dev
+    - libelf-dev
+    - libdw-dev
+
 before_script:
-  - pip install 'travis-cargo<0.2' --user && export PATH=$HOME/.local/bin:$PATH
+- smtp-sink 2525 1000&
+
 script:
-  - |
-      travis-cargo build &&
-      travis-cargo test &&
-      travis-cargo doc
+- travis-cargo build
+- travis-cargo test
+- travis-cargo doc
+
 after_success:
-  - travis-cargo --only stable doc-upload
-  - travis-cargo --only stable coveralls
+- ./.travis/doc.sh
+- ./.travis/coverage.sh
+- travis-cargo --only nightly bench
 
 env:
   global:

.travis/coverage.sh

@@ -0,0 +1,20 @@
+#!/bin/bash
+
+set -o errexit
+
+if [ "$TRAVIS_RUST_VERSION" != "stable" ]; then
+    exit 0
+fi
+
+cargo test --no-run
+
+wget https://github.com/SimonKagstrom/kcov/archive/master.tar.gz
+tar xzf master.tar.gz
+mkdir kcov-master/build
+cd kcov-master/build
+cmake ..
+make
+make install DESTDIR=../tmp
+cd ../..
+ls target/debug
+./kcov-master/tmp/usr/local/bin/kcov --coveralls-id=$TRAVIS_JOB_ID --exclude-pattern=/.cargo target/kcov target/debug/lettre-*

.travis/doc.sh

@@ -0,0 +1,38 @@
+#!/bin/bash
+
+set -o errexit
+
+if [ "$TRAVIS_RUST_VERSION" != "stable" ] || [ "$TRAVIS_PULL_REQUEST" != "false" ]; then
+    exit 0
+fi
+
+cargo clean
+cargo doc --no-deps
+
+git clone --branch gh-pages "https://$GH_TOKEN@github.com/${TRAVIS_REPO_SLUG}.git" deploy_docs
+cd deploy_docs
+
+git config user.email "contact@amousset.me"
+git config user.name "Alexis Mousset"
+
+if [ "$TRAVIS_BRANCH" == "master"  ]; then
+    rm -rf master
+    mv ../target/doc ./master
+    echo "<meta http-equiv=refresh content=0;url=lettre/index.html>" > ./master/index.html
+elif [ "$TRAVIS_TAG" != ""  ]; then
+    rm -rf $TRAVIS_TAG
+    mv ../target/doc ./$TRAVIS_TAG
+    echo "<meta http-equiv=refresh content=0;url=lettre/index.html>" > ./$TRAVIS_TAG/index.html
+
+    latest=$(echo * | tr " " "\n" | sort -V -r | head -n1)
+    if [ "$TRAVIS_TAG" == "$latest" ]; then
+
+        echo "<meta http-equiv=refresh content=0;url=$latest/lettre/index.html>" > index.html
+    fi
+else
+    exit 0
+fi
+
+git add -A .
+git commit -m "Rebuild pages at ${TRAVIS_COMMIT}"
+git push --quiet origin gh-pages

CHANGELOG.md

@@ -0,0 +1,43 @@
+### v0.6.3 (2022-1--21)
+
+* **transport**: Allow using openssl 0.10
+
+### v0.6.2 (2017-02-18)
+
+#### Features
+
+* **all**
+  * Update uuid crate to 0.4
+  * Update env-logger crate to 0.4
+  * Update openssl crate to 0.9
+
+### v0.6.1 (2016-10-19)
+
+#### Features
+
+* **documentation**
+  * #91: Build seperate docs for each release
+  * #96: Add complete documentation information to README
+
+#### Bugfixes
+
+* **email**
+  * #85: Use address-list for "To", "From" etc.
+
+* **tests**
+  * #93: Force building tests before coverage computing
+
+### v0.6.0 (2016-05-05)
+
+#### Features
+
+* **email**
+  *  multipart support
+  *  add non-consuming methods for Email builders
+
+#### Beaking Change
+
+* **email**
+  * `add_header` does not return the builder anymore, 
+    for consistency with other methods. Use the `header`
+    method instead

CONTRIBUTING.md

@@ -0,0 +1,38 @@
+## Contributing to Lettre
+
+The following guidelines are inspired from the [hyper project](https://github.com/hyperium/hyper/blob/master/CONTRIBUTING.md).
+
+### Code formatting
+
+All code must be formatted using `rustfmt`.
+
+### Commit Message Format
+
+Each commit message consists of a header, a body and a footer. The header has a special format that includes a type, a scope and a subject:
+
+```text
+<type>(<scope>): <subject> <BLANK LINE> <body> <BLANK LINE> <footer>
+```
+
+Any line of the commit message cannot be longer 72 characters.
+
+**type** must be one of the following:
+
+    feat: A new feature
+    fix: A bug fix
+    docs: Documentation only changes
+    style: Changes that do not affect the meaning of the code (white-space, formatting, missing semi-colons, etc)
+    refactor: A code change that neither fixes a bug or adds a feature
+    perf: A code change that improves performance
+    test: Adding missing tests
+    chore: Changes to the build process or auxiliary tools and libraries such as documentation generation
+
+**scope** is the lettre part that is being touched. Examples:
+
+    email
+    transport-smtp
+    transport-file
+    transport
+    all
+
+The body explains the change, and the footer contains relevant changelog notes and references to fixed issues.

Cargo.toml

@@ -1,27 +1,28 @@
 [package]
 
-name = "smtp"
-version = "0.3.0"
-description = "Simple SMTP client"
+name = "lettre"
+version = "0.6.3"
+description = "Email client"
 readme = "README.md"
-documentation = "http://amousset.me/rust-smtp/smtp/"
-repository = "https://github.com/amousset/rust-smtp"
+documentation = "https://lettre.github.io/lettre/"
+repository = "https://github.com/lettre/lettre"
 license = "MIT"
-authors = ["Alexis Mousset <alexis.mousset@gmx.fr>"]
+authors = ["Alexis Mousset <contact@amousset.me>"]
 keywords = ["email", "smtp", "mailer"]
 
 [dependencies]
-time = "0.1"
-uuid = "0.1"
-log = "0.3"
-rustc-serialize = "0.3"
-rust-crypto = "0.2"
-bufstream = "0.1"
-email = "0.0"
-openssl = "0.6"
+bufstream = "^0.1"
+email = "^0.0"
+log = "^0.3"
+mime = "^0.2"
+openssl = "> 0.9, < 0.11"
+rustc-serialize = "^0.3"
+rust-crypto = "^0.2"
+time = "^0.1"
+uuid = { version = "^0.4", features = ["v4"] }
 
 [dev-dependencies]
-env_logger = "0.3"
+env_logger = "^0.4"
 
 [features]
 unstable = []

README.md

@@ -1,22 +1,52 @@
-rust-smtp [![Build Status](https://travis-ci.org/amousset/rust-smtp.svg?branch=master)](https://travis-ci.org/amousset/rust-smtp) [![Coverage Status](https://coveralls.io/repos/github/amousset/rust-smtp/badge.svg?branch=master)](https://coveralls.io/github/amousset/rust-smtp?branch=master) [![Crate](https://meritbadge.herokuapp.com/smtp)](https://crates.io/crates/smtp) [![MIT licensed](https://img.shields.io/badge/license-MIT-blue.svg)](./LICENSE)
-=========
+# lettre
+[![Build Status](https://travis-ci.org/lettre/lettre.svg?branch=master)](https://travis-ci.org/lettre/lettre)
+[![Build status](https://ci.appveyor.com/api/projects/status/mpwglemugjtkps2d/branch/master?svg=true)](https://ci.appveyor.com/project/amousset/lettre/branch/master)
+[![Coverage Status](https://coveralls.io/repos/github/lettre/lettre/badge.svg?branch=master)](https://coveralls.io/github/lettre/lettre?branch=master)
+[![Crate](https://img.shields.io/crates/v/lettre.svg)](https://crates.io/crates/lettre)
+[![MIT licensed](https://img.shields.io/badge/license-MIT-blue.svg)](./LICENSE)
+[![Gitter](https://badges.gitter.im/lettre/lettre.svg)](https://gitter.im/lettre/lettre?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge)
 
-This library implements a simple SMTP client.
-See the [documentation](http://amousset.github.io/rust-smtp/smtp/) for more information.
+This is an email library written in Rust.
 
-Install
--------
+## Features
+
+Lettre provides the following features:
+
+* Multiple transport methods
+* Unicode support (for email content and addresses)
+* Secure delivery with SMTP using encryption and authentication
+* Easy email builders
+
+## Documentation
+
+Released versions:
+
+* [latest](https://lettre.github.io/lettre/)
+* [v0.6.3](https://lettre.github.io/lettre/v0.6.3/lettre/)
+* [v0.6.2](https://lettre.github.io/lettre/v0.6.2/lettre/)
+* [v0.6.1](https://lettre.github.io/lettre/v0.6.1/lettre/)
+* [v0.6.0](https://lettre.github.io/lettre/v0.6.0/lettre/)
+* [v0.5.1](https://lettre.github.io/lettre/v0.5.1/lettre/)
+
+Development version:
+
+* [master](https://lettre.github.io/lettre/master/lettre/)
+
+## Install
 
 To use this library, add the following to your `Cargo.toml`:
 
 ```toml
 [dependencies]
-smtp = "0.2"
+lettre = "0.6"
 ```
 
-License
--------
+## Testing
+
+The tests require an open mail server listening locally on port 25.
+
+## License
 
 This program is distributed under the terms of the MIT license.
 
-See LICENSE for details.
+See [LICENSE](./LICENSE) for details.

benches/transport_smtp.rs

@@ -0,0 +1,44 @@
+#![feature(test)]
+
+extern crate lettre;
+extern crate test;
+
+use lettre::transport::smtp::SmtpTransportBuilder;
+use lettre::transport::EmailTransport;
+use lettre::email::EmailBuilder;
+
+#[bench]
+fn bench_simple_send(b: &mut test::Bencher) {
+    let mut sender = SmtpTransportBuilder::new("127.0.0.1:2525").unwrap().build();
+    b.iter(|| {
+        let email = EmailBuilder::new()
+                        .to("root@localhost")
+                        .from("user@localhost")
+                        .body("Hello World!")
+                        .subject("Hello")
+                        .build()
+                        .unwrap();
+        let result = sender.send(email);
+        assert!(result.is_ok());
+    });
+}
+
+#[bench]
+fn bench_reuse_send(b: &mut test::Bencher) {
+    let mut sender = SmtpTransportBuilder::new("127.0.0.1:2525")
+                         .unwrap()
+                         .connection_reuse(true)
+                         .build();
+    b.iter(|| {
+        let email = EmailBuilder::new()
+                        .to("root@localhost")
+                        .from("user@localhost")
+                        .body("Hello World!")
+                        .subject("Hello")
+                        .build()
+                        .unwrap();
+        let result = sender.send(email);
+        assert!(result.is_ok());
+    });
+    sender.close()
+}

examples/client.rs

@@ -1,54 +0,0 @@
-#[macro_use]
-extern crate log;
-extern crate env_logger;
-extern crate smtp;
-
-use std::sync::{Arc, Mutex};
-use std::thread;
-
-use smtp::sender::SenderBuilder;
-use smtp::email::EmailBuilder;
-
-fn main() {
-    env_logger::init().unwrap();
-
-    let sender = Arc::new(Mutex::new(SenderBuilder::localhost().unwrap().hello_name("localhost")
-        .enable_connection_reuse(true).build()));
-
-	let mut threads = Vec::new();
-    for _ in 1..5 {
-
-    	let th_sender = sender.clone();
-    	threads.push(thread::spawn(move || {
-
-        	let email = EmailBuilder::new()
-                    	.to("user@localhost")
-                    	.from("user@localhost")
-                    	.body("Hello World!")
-                    	.subject("Hello")
-                    	.build();
-
-    		let _ = th_sender.lock().unwrap().send(email);
-		}));
-    }
-
-    for thread in threads {
-    	let _ = thread.join();
-    }
-
-    let email = EmailBuilder::new()
-                    .to("user@localhost")
-                    .from("user@localhost")
-                    .body("Hello World!")
-                    .subject("Hello Bis")
-                    .build();
-
-	let mut sender = sender.lock().unwrap();
-    let result = sender.send(email);
-    sender.close();
-
-    match result {
-        Ok(..) => info!("Email sent successfully"),
-        Err(error) => error!("{:?}", error),
-    }
-}

rustfmt.toml

@@ -0,0 +1 @@
+reorder_imports = true

src/authentication.rs

@@ -1,109 +0,0 @@
-//! Provides authentication mecanisms
-
-use std::fmt::{Display, Formatter};
-use std::fmt;
-
-use serialize::base64::{self, ToBase64, FromBase64};
-use serialize::hex::ToHex;
-use crypto::hmac::Hmac;
-use crypto::md5::Md5;
-use crypto::mac::Mac;
-
-use NUL;
-use error::Error;
-
-/// Represents authentication mecanisms
-#[derive(PartialEq,Eq,Copy,Clone,Hash,Debug)]
-pub enum Mecanism {
-    /// PLAIN authentication mecanism
-    /// RFC 4616: https://tools.ietf.org/html/rfc4616
-    Plain,
-    /// CRAM-MD5 authentication mecanism
-    /// RFC 2195: https://tools.ietf.org/html/rfc2195
-    CramMd5,
-}
-
-impl Display for Mecanism {
-    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
-        write!(f,
-               "{}",
-               match *self {
-                   Mecanism::Plain => "PLAIN",
-                   Mecanism::CramMd5 => "CRAM-MD5",
-               })
-    }
-}
-
-impl Mecanism {
-    /// Does the mecanism supports initial response
-    pub fn supports_initial_response(&self) -> bool {
-        match *self {
-            Mecanism::Plain => true,
-            Mecanism::CramMd5 => false,
-        }
-    }
-
-    /// Returns the string to send to the server, using the provided username, password and
-    /// challenge in some cases
-    pub fn response(&self,
-                    username: &str,
-                    password: &str,
-                    challenge: Option<&str>)
-                    -> Result<String, Error> {
-        match *self {
-            Mecanism::Plain => {
-                match challenge {
-                    Some(_) => Err(Error::ClientError("This mecanism does not expect a challenge")),
-                    None => Ok(format!("{}{}{}{}", NUL, username, NUL, password)
-                                   .as_bytes()
-                                   .to_base64(base64::STANDARD)),
-                }
-            }
-            Mecanism::CramMd5 => {
-                let encoded_challenge = match challenge {
-                    Some(challenge) => challenge,
-                    None => return Err(Error::ClientError("This mecanism does expect a challenge")),
-                };
-
-                let decoded_challenge = match encoded_challenge.from_base64() {
-                    Ok(challenge) => challenge,
-                    Err(error) => return Err(Error::ChallengeParsingError(error)),
-                };
-
-                let mut hmac = Hmac::new(Md5::new(), password.as_bytes());
-                hmac.input(&decoded_challenge);
-
-                Ok(format!("{} {}", username, hmac.result().code().to_hex())
-                       .as_bytes()
-                       .to_base64(base64::STANDARD))
-            }
-        }
-    }
-}
-
-#[cfg(test)]
-mod test {
-    use super::Mecanism;
-
-    #[test]
-    fn test_plain() {
-        let mecanism = Mecanism::Plain;
-
-        assert_eq!(mecanism.response("username", "password", None).unwrap(),
-                   "AHVzZXJuYW1lAHBhc3N3b3Jk");
-        assert!(mecanism.response("username", "password", Some("test")).is_err());
-    }
-
-    #[test]
-    fn test_cram_md5() {
-        let mecanism = Mecanism::CramMd5;
-
-        assert_eq!(mecanism.response("alice",
-                                     "wonderland",
-                                     Some("PDE3ODkzLjEzMjA2NzkxMjNAdGVzc2VyYWN0LnN1c2FtLmluPg=="))
-                           .unwrap(),
-                   "YWxpY2UgNjRiMmE0M2MxZjZlZDY4MDZhOTgwOTE0ZTIzZTc1ZjA=");
-        assert!(mecanism.response("alice", "wonderland", Some("tést")).is_err());
-        assert!(mecanism.response("alice", "wonderland", None).is_err());
-    }
-}

src/email.rs

@@ -1,348 +0,0 @@
-//! Simple email (very incomplete)
-
-use std::fmt::{Display, Formatter, Result};
-
-use email_format::{MimeMessage, Header, Mailbox};
-use time::{now, Tm};
-use uuid::Uuid;
-
-/// Converts an adress or an address with an alias to a `Address`
-pub trait ToHeader {
-    /// Converts to a `Header` struct
-    fn to_header(&self) -> Header;
-}
-
-impl ToHeader for Header {
-    fn to_header(&self) -> Header {
-        (*self).clone()
-    }
-}
-
-impl<'a> ToHeader for (&'a str, &'a str) {
-    fn to_header(&self) -> Header {
-        let (name, value) = *self;
-        Header::new(name.to_string(), value.to_string())
-    }
-}
-
-/// Converts an adress or an address with an alias to a `Mailbox`
-pub trait ToMailbox {
-    /// Converts to a `Mailbox` struct
-    fn to_mailbox(&self) -> Mailbox;
-}
-
-impl ToMailbox for Mailbox {
-    fn to_mailbox(&self) -> Mailbox {
-        (*self).clone()
-    }
-}
-
-impl<'a> ToMailbox for &'a str {
-    fn to_mailbox(&self) -> Mailbox {
-        Mailbox::new(self.to_string())
-    }
-}
-
-impl<'a> ToMailbox for (&'a str, &'a str) {
-    fn to_mailbox(&self) -> Mailbox {
-        let (address, alias) = *self;
-        Mailbox::new_with_name(alias.to_string(), address.to_string())
-    }
-}
-
-/// Builds an `Email` structure
-#[derive(PartialEq,Eq,Clone,Debug)]
-pub struct EmailBuilder {
-    /// Email content
-    content: Email,
-    /// Date issued
-    date_issued: bool,
-}
-
-/// Simple email representation
-#[derive(PartialEq,Eq,Clone,Debug)]
-pub struct Email {
-    /// Message
-    message: MimeMessage,
-    /// The enveloppe recipients addresses
-    to: Vec<String>,
-    /// The enveloppe sender address
-    from: Option<String>,
-    /// Message-ID
-    message_id: Uuid,
-}
-
-impl Display for Email {
-    fn fmt(&self, f: &mut Formatter) -> Result {
-        write!(f, "{}", self.message.as_string())
-    }
-}
-
-impl EmailBuilder {
-    /// Creates a new empty email
-    pub fn new() -> EmailBuilder {
-        let current_message = Uuid::new_v4();
-
-        let mut email = Email {
-            message: MimeMessage::new_blank_message(),
-            to: vec![],
-            from: None,
-            message_id: current_message,
-        };
-
-        match Header::new_with_value("Message-ID".to_string(),
-                                     format!("<{}@rust-smtp>", current_message)) {
-            Ok(header) => email.message.headers.insert(header),
-            Err(_) => (),
-        }
-
-        EmailBuilder {
-            content: email,
-            date_issued: false,
-        }
-    }
-
-    /// Sets the email body
-    pub fn body(mut self, body: &str) -> EmailBuilder {
-        self.content.message.body = body.to_string();
-        self
-    }
-
-    /// Add a generic header
-    pub fn add_header<A: ToHeader>(mut self, header: A) -> EmailBuilder {
-        self.insert_header(header);
-        self
-    }
-
-    fn insert_header<A: ToHeader>(&mut self, header: A) {
-        self.content.message.headers.insert(header.to_header());
-    }
-
-    /// Adds a `From` header and store the sender address
-    pub fn from<A: ToMailbox>(mut self, address: A) -> EmailBuilder {
-        let mailbox = address.to_mailbox();
-        self.insert_header(("From", mailbox.to_string().as_ref()));
-        self.content.from = Some(mailbox.address);
-        self
-    }
-
-    /// Adds a `To` header and store the recipient address
-    pub fn to<A: ToMailbox>(mut self, address: A) -> EmailBuilder {
-        let mailbox = address.to_mailbox();
-        self.insert_header(("To", mailbox.to_string().as_ref()));
-        self.content.to.push(mailbox.address);
-        self
-    }
-
-    /// Adds a `Cc` header and store the recipient address
-    pub fn cc<A: ToMailbox>(mut self, address: A) -> EmailBuilder {
-        let mailbox = address.to_mailbox();
-        self.insert_header(("Cc", mailbox.to_string().as_ref()));
-        self.content.to.push(mailbox.address);
-        self
-    }
-
-    /// Adds a `Reply-To` header
-    pub fn reply_to<A: ToMailbox>(mut self, address: A) -> EmailBuilder {
-        let mailbox = address.to_mailbox();
-        self.insert_header(("Reply-To", mailbox.to_string().as_ref()));
-        self
-    }
-
-    /// Adds a `Sender` header
-    pub fn sender<A: ToMailbox>(mut self, address: A) -> EmailBuilder {
-        let mailbox = address.to_mailbox();
-        self.insert_header(("Sender", mailbox.to_string().as_ref()));
-        self.content.from = Some(mailbox.address);
-        self
-    }
-
-    /// Adds a `Subject` header
-    pub fn subject(mut self, subject: &str) -> EmailBuilder {
-        self.insert_header(("Subject", subject));
-        self
-    }
-
-    /// Adds a `Date` header with the given date
-    pub fn date(mut self, date: &Tm) -> EmailBuilder {
-        self.insert_header(("Date", Tm::rfc822z(date).to_string().as_ref()));
-        self.date_issued = true;
-        self
-    }
-
-    /// Build the Email
-    pub fn build(mut self) -> Email {
-        if !self.date_issued {
-            self.insert_header(("Date", Tm::rfc822z(&now()).to_string().as_ref()));
-        }
-        self.content.message.update_headers();
-        self.content
-    }
-}
-
-
-/// Email sendable by an SMTP client
-pub trait SendableEmail {
-    /// From address
-    fn from_address(&self) -> Option<String>;
-    /// To addresses
-    fn to_addresses(&self) -> Option<Vec<String>>;
-    /// Message content
-    fn message(&self) -> Option<String>;
-    /// Message ID
-    fn message_id(&self) -> Option<String>;
-}
-
-/// Minimal email structure
-pub struct SimpleSendableEmail {
-    /// From address
-    from: String,
-    /// To addresses
-    to: Vec<String>,
-    /// Message
-    message: String,
-}
-
-impl SimpleSendableEmail {
-    /// Returns a new email
-    pub fn new(from_address: &str, to_address: &str, message: &str) -> SimpleSendableEmail {
-        SimpleSendableEmail {
-            from: from_address.to_string(),
-            to: vec![to_address.to_string()],
-            message: message.to_string(),
-        }
-    }
-}
-
-impl SendableEmail for SimpleSendableEmail {
-    fn from_address(&self) -> Option<String> {
-        Some(self.from.clone())
-    }
-
-    fn to_addresses(&self) -> Option<Vec<String>> {
-        Some(self.to.clone())
-    }
-
-    fn message(&self) -> Option<String> {
-        Some(self.message.clone())
-    }
-
-    fn message_id(&self) -> Option<String> {
-        Some(format!("<{}@rust-smtp>", Uuid::new_v4()))
-    }
-}
-
-impl SendableEmail for Email {
-    /// Return the to addresses, and fails if it is not set
-    fn to_addresses(&self) -> Option<Vec<String>> {
-        if self.to.is_empty() {
-            None
-        } else {
-            Some(self.to.clone())
-        }
-    }
-
-    /// Return the from address, and fails if it is not set
-    fn from_address(&self) -> Option<String> {
-        match self.from {
-            Some(ref from_address) => Some(from_address.clone()),
-            None => None,
-        }
-    }
-
-    fn message(&self) -> Option<String> {
-        Some(format!("{}", self))
-    }
-
-    fn message_id(&self) -> Option<String> {
-        Some(format!("{}", self.message_id))
-    }
-}
-
-#[cfg(test)]
-mod test {
-    use time::now;
-
-    use uuid::Uuid;
-    use email_format::{MimeMessage, Header};
-
-    use super::{SendableEmail, EmailBuilder, Email};
-
-    #[test]
-    fn test_email_display() {
-        let current_message = Uuid::new_v4();
-
-        let mut email = Email {
-            message: MimeMessage::new_blank_message(),
-            to: vec![],
-            from: None,
-            message_id: current_message,
-        };
-
-        email.message.headers.insert(Header::new_with_value("Message-ID".to_string(),
-                                                            format!("<{}@rust-smtp>",
-                                                                    current_message))
-                                         .unwrap());
-
-        email.message
-             .headers
-             .insert(Header::new_with_value("To".to_string(), "to@example.com".to_string())
-                         .unwrap());
-
-        email.message.body = "body".to_string();
-
-        assert_eq!(format!("{}", email),
-                   format!("Message-ID: <{}@rust-smtp>\r\nTo: to@example.com\r\n\r\nbody\r\n",
-                           current_message));
-        assert_eq!(current_message.to_string(), email.message_id().unwrap());
-    }
-
-    #[test]
-    fn test_email_builder() {
-        let email_builder = EmailBuilder::new();
-        let date_now = now();
-
-        let email = email_builder.to("user@localhost")
-                                 .from("user@localhost")
-                                 .cc(("cc@localhost", "Alias"))
-                                 .reply_to("reply@localhost")
-                                 .sender("sender@localhost")
-                                 .body("Hello World!")
-                                 .date(&date_now)
-                                 .subject("Hello")
-                                 .add_header(("X-test", "value"))
-                                 .build();
-
-        assert_eq!(format!("{}", email),
-                   format!("Message-ID: <{}@rust-smtp>\r\nTo: <user@localhost>\r\nFrom: \
-                            <user@localhost>\r\nCc: \"Alias\" <cc@localhost>\r\nReply-To: \
-                            <reply@localhost>\r\nSender: <sender@localhost>\r\nDate: \
-                            {}\r\nSubject: Hello\r\nX-test: value\r\n\r\nHello World!\r\n",
-                           email.message_id().unwrap(),
-                           date_now.rfc822z()));
-    }
-
-    #[test]
-    fn test_email_sendable() {
-        let email_builder = EmailBuilder::new();
-        let date_now = now();
-
-        let email = email_builder.to("user@localhost")
-                                 .from("user@localhost")
-                                 .cc(("cc@localhost", "Alias"))
-                                 .reply_to("reply@localhost")
-                                 .sender("sender@localhost")
-                                 .body("Hello World!")
-                                 .date(&date_now)
-                                 .subject("Hello")
-                                 .add_header(("X-test", "value"))
-                                 .build();
-
-        assert_eq!(email.from_address().unwrap(),
-                   "sender@localhost".to_string());
-        assert_eq!(email.to_addresses().unwrap(),
-                   vec!["user@localhost".to_string(), "cc@localhost".to_string()]);
-        assert_eq!(email.message().unwrap(), format!("{}", email));
-    }
-
-}

src/email/error.rs

@@ -0,0 +1,31 @@
+//! Error and result type for emails
+
+
+use self::Error::*;
+use std::error::Error as StdError;
+use std::fmt;
+use std::fmt::{Display, Formatter};
+
+/// An enum of all error kinds.
+#[derive(Debug)]
+pub enum Error {
+    /// Missinf sender
+    MissingFrom,
+    /// Missing recipient
+    MissingTo,
+}
+
+impl Display for Error {
+    fn fmt(&self, fmt: &mut Formatter) -> Result<(), fmt::Error> {
+        fmt.write_str(self.description())
+    }
+}
+
+impl StdError for Error {
+    fn description(&self) -> &str {
+        match *self {
+            MissingFrom => "the sender is missing",
+            MissingTo => "the recipient is missing",
+        }
+    }
+}

src/email/mod.rs

@@ -0,0 +1,799 @@
+//! Simple email representation
+pub mod error;
+
+use email::error::Error;
+
+use email_format::{Header, Mailbox, Address, MimeMessage, MimeMultipartType};
+use mime::Mime;
+use std::fmt;
+use std::fmt::{Display, Formatter};
+use time::{Tm, now};
+use uuid::Uuid;
+
+/// Converts an address or an address with an alias to a `Header`
+pub trait ToHeader {
+    /// Converts to a `Header` struct
+    fn to_header(&self) -> Header;
+}
+
+impl ToHeader for Header {
+    fn to_header(&self) -> Header {
+        self.clone()
+    }
+}
+
+impl<'a> ToHeader for (&'a str, &'a str) {
+    fn to_header(&self) -> Header {
+        let (name, value) = *self;
+        Header::new(name.to_string(), value.to_string())
+    }
+}
+
+/// Converts an adress or an address with an alias to a `Mailbox`
+pub trait ToMailbox {
+    /// Converts to a `Mailbox` struct
+    fn to_mailbox(&self) -> Mailbox;
+}
+
+impl ToMailbox for Mailbox {
+    fn to_mailbox(&self) -> Mailbox {
+        (*self).clone()
+    }
+}
+
+impl<'a> ToMailbox for &'a str {
+    fn to_mailbox(&self) -> Mailbox {
+        Mailbox::new(self.to_string())
+    }
+}
+
+impl<'a> ToMailbox for (&'a str, &'a str) {
+    fn to_mailbox(&self) -> Mailbox {
+        let (address, alias) = *self;
+        Mailbox::new_with_name(alias.to_string(), address.to_string())
+    }
+}
+
+/// Can be transformed to a sendable email
+pub trait IntoEmail {
+    /// Builds an email
+    fn into_email(&self) -> Result<Email, Error>;
+}
+
+impl IntoEmail for SimpleEmail {
+    fn into_email(&self) -> Result<Email, Error> {
+        let mut builder = EmailBuilder::new();
+
+        if self.from.is_some() {
+            builder.add_from(self.from.as_ref().unwrap().as_str().to_mailbox());
+        }
+
+        for to_address in self.to.as_slice() {
+            builder.add_to(to_address.as_str().to_mailbox());
+        }
+
+        for cc_address in self.cc.as_slice() {
+            builder.add_cc(cc_address.as_str().to_mailbox());
+        }
+
+        // No bcc for now
+
+        if self.reply_to.is_some() {
+            builder.add_reply_to(self.reply_to.as_ref().unwrap().as_str().to_mailbox());
+        }
+
+        if self.subject.is_some() {
+            builder.set_subject(self.subject.as_ref().unwrap().as_str());
+        }
+
+        // No date for now
+
+        match (self.text.as_ref(), self.html.as_ref()) {
+            (Some(text), Some(html)) => builder.set_alternative(html.as_str(), text.as_str()),
+            (Some(text), None) => builder.set_text(text.as_str()),
+            (None, Some(html)) => builder.set_html(html.as_str()),
+            (None, None) => (),
+        }
+
+        for header in self.headers.as_slice() {
+            builder.add_header(header.to_header());
+        }
+
+        Ok(builder.build().unwrap())
+    }
+}
+
+
+/// Simple representation of an email, useful for some transports
+#[derive(PartialEq,Eq,Clone,Debug,Default)]
+pub struct SimpleEmail {
+    from: Option<String>,
+    to: Vec<String>,
+    cc: Vec<String>,
+    // bcc: Vec<String>,
+    reply_to: Option<String>,
+    subject: Option<String>,
+    date: Option<Tm>,
+    html: Option<String>,
+    text: Option<String>,
+    // attachments: Vec<String>,
+    headers: Vec<Header>,
+}
+
+impl SimpleEmail {
+    /// Adds a generic header
+    pub fn header<A: ToHeader>(mut self, header: A) -> SimpleEmail {
+        self.add_header(header);
+        self
+    }
+
+    /// Adds a generic header
+    pub fn add_header<A: ToHeader>(&mut self, header: A) {
+        self.headers.push(header.to_header());
+    }
+
+    /// Adds a `From` header and stores the sender address
+    pub fn from<A: ToMailbox>(mut self, address: A) -> SimpleEmail {
+        self.add_from(address);
+        self
+    }
+
+    /// Adds a `From` header and stores the sender address
+    pub fn add_from<A: ToMailbox>(&mut self, address: A) {
+        let mailbox = address.to_mailbox();
+        self.from = Some(mailbox.address);
+    }
+
+    /// Adds a `To` header and stores the recipient address
+    pub fn to<A: ToMailbox>(mut self, address: A) -> SimpleEmail {
+        self.add_to(address);
+        self
+    }
+
+    /// Adds a `To` header and stores the recipient address
+    pub fn add_to<A: ToMailbox>(&mut self, address: A) {
+        let mailbox = address.to_mailbox();
+        self.to.push(mailbox.address);
+    }
+
+    /// Adds a `Cc` header and stores the recipient address
+    pub fn cc<A: ToMailbox>(mut self, address: A) -> SimpleEmail {
+        self.add_cc(address);
+        self
+    }
+
+    /// Adds a `Cc` header and stores the recipient address
+    pub fn add_cc<A: ToMailbox>(&mut self, address: A) {
+        let mailbox = address.to_mailbox();
+        self.cc.push(mailbox.address);
+    }
+
+    /// Adds a `Reply-To` header
+    pub fn reply_to<A: ToMailbox>(mut self, address: A) -> SimpleEmail {
+        self.add_reply_to(address);
+        self
+    }
+
+    /// Adds a `Reply-To` header
+    pub fn add_reply_to<A: ToMailbox>(&mut self, address: A) {
+        let mailbox = address.to_mailbox();
+        self.reply_to = Some(mailbox.address);
+    }
+
+    /// Adds a `Subject` header
+    pub fn subject(mut self, subject: &str) -> SimpleEmail {
+        self.set_subject(subject);
+        self
+    }
+
+    /// Adds a `Subject` header
+    pub fn set_subject(&mut self, subject: &str) {
+        self.subject = Some(subject.to_string());
+    }
+
+    /// Adds a `Date` header with the given date
+    pub fn date(mut self, date: &Tm) -> SimpleEmail {
+        self.set_date(date);
+        self
+    }
+
+    /// Adds a `Date` header with the given date
+    pub fn set_date(&mut self, date: &Tm) {
+        self.date = Some(date.clone());
+    }
+
+    /// Sets the email body to plain text content
+    pub fn text(mut self, body: &str) -> SimpleEmail {
+        self.set_text(body);
+        self
+    }
+
+    /// Sets the email body to plain text content
+    pub fn set_text(&mut self, body: &str) {
+        self.text = Some(body.to_string());
+    }
+
+    /// Sets the email body to HTML content
+    pub fn html(mut self, body: &str) -> SimpleEmail {
+        self.set_html(body);
+        self
+    }
+
+    /// Sets the email body to HTML content
+    pub fn set_html(&mut self, body: &str) {
+        self.html = Some(body.to_string());
+    }
+}
+
+/// Builds a `MimeMessage` structure
+#[derive(PartialEq,Eq,Clone,Debug)]
+pub struct PartBuilder {
+    /// Message
+    message: MimeMessage,
+}
+
+/// Builds an `Email` structure
+#[derive(PartialEq,Eq,Clone,Debug)]
+pub struct EmailBuilder {
+    /// Message
+    message: PartBuilder,
+    /// The recipients' addresses for the mail header
+    to_header: Vec<Address>,
+    /// The sender addresses for the mail header
+    from_header: Vec<Address>,
+    /// The Cc addresses for the mail header
+    cc_header: Vec<Address>,
+    /// The Reply-To addresses for the mail header
+    reply_to_header: Vec<Address>,
+    /// The sender address for the mail header
+    sender_header: Option<Mailbox>,
+    /// The envelope recipients' addresses
+    to: Vec<String>,
+    /// The envelope sender address
+    from: Option<String>,
+    /// Date issued
+    date_issued: bool,
+}
+
+/// Simple email enveloppe representation
+#[derive(PartialEq,Eq,Clone,Debug)]
+pub struct Envelope {
+    /// The envelope recipients' addresses
+    to: Vec<String>,
+    /// The envelope sender address
+    from: String,
+}
+
+/// Simple email representation
+#[derive(PartialEq,Eq,Clone,Debug)]
+pub struct Email {
+    /// Message
+    message: MimeMessage,
+    /// Envelope
+    envelope: Envelope,
+    /// Message-ID
+    message_id: Uuid,
+}
+
+impl Display for Email {
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        write!(f, "{}", self.message.as_string())
+    }
+}
+
+impl PartBuilder {
+    /// Creates a new empty part
+    pub fn new() -> PartBuilder {
+        PartBuilder { message: MimeMessage::new_blank_message() }
+    }
+
+    /// Adds a generic header
+    pub fn header<A: ToHeader>(mut self, header: A) -> PartBuilder {
+        self.add_header(header);
+        self
+    }
+
+    /// Adds a generic header
+    pub fn add_header<A: ToHeader>(&mut self, header: A) {
+        self.message.headers.insert(header.to_header());
+    }
+
+    /// Sets the body
+    pub fn body(mut self, body: &str) -> PartBuilder {
+        self.set_body(body);
+        self
+    }
+
+    /// Sets the body
+    pub fn set_body(&mut self, body: &str) {
+        self.message.body = body.to_string();
+    }
+
+
+    /// Defines a `MimeMultipartType` value
+    pub fn message_type(mut self, mime_type: MimeMultipartType) -> PartBuilder {
+        self.set_message_type(mime_type);
+        self
+    }
+
+    /// Defines a `MimeMultipartType` value
+    pub fn set_message_type(&mut self, mime_type: MimeMultipartType) {
+        self.message.message_type = Some(mime_type);
+    }
+
+    /// Adds a `ContentType` header with the given MIME type
+    pub fn content_type(mut self, content_type: Mime) -> PartBuilder {
+        self.set_content_type(content_type);
+        self
+    }
+
+    /// Adds a `ContentType` header with the given MIME type
+    pub fn set_content_type(&mut self, content_type: Mime) {
+        self.add_header(("Content-Type", format!("{}", content_type).as_ref()));
+    }
+
+    /// Adds a child part
+    pub fn child(mut self, child: MimeMessage) -> PartBuilder {
+        self.add_child(child);
+        self
+    }
+
+    /// Adds a child part
+    pub fn add_child(&mut self, child: MimeMessage) {
+        self.message.children.push(child);
+    }
+
+    /// Gets builded `MimeMessage`
+    pub fn build(mut self) -> MimeMessage {
+        self.message.update_headers();
+        self.message
+    }
+}
+
+impl EmailBuilder {
+    /// Creates a new empty email
+    pub fn new() -> EmailBuilder {
+        EmailBuilder {
+            message: PartBuilder::new(),
+            to_header: vec![],
+            from_header: vec![],
+            cc_header: vec![],
+            reply_to_header: vec![],
+            sender_header: None,
+            to: vec![],
+            from: None,
+            date_issued: false,
+        }
+    }
+
+    /// Sets the email body
+    pub fn body(mut self, body: &str) -> EmailBuilder {
+        self.message.set_body(body);
+        self
+    }
+
+    /// Sets the email body
+    pub fn set_body(&mut self, body: &str) {
+        self.message.set_body(body);
+    }
+
+    /// Add a generic header
+    pub fn header<A: ToHeader>(mut self, header: A) -> EmailBuilder {
+        self.message.add_header(header);
+        self
+    }
+
+    /// Add a generic header
+    pub fn add_header<A: ToHeader>(&mut self, header: A) {
+        self.message.add_header(header);
+    }
+
+    /// Adds a `From` header and stores the sender address
+    pub fn from<A: ToMailbox>(mut self, address: A) -> EmailBuilder {
+        self.add_from(address);
+        self
+    }
+
+    /// Adds a `From` header and stores the sender address
+    pub fn add_from<A: ToMailbox>(&mut self, address: A) {
+        let mailbox = address.to_mailbox();
+        self.from = Some(mailbox.address.clone());
+        self.from_header.push(Address::Mailbox(mailbox));
+    }
+
+    /// Adds a `To` header and stores the recipient address
+    pub fn to<A: ToMailbox>(mut self, address: A) -> EmailBuilder {
+        self.add_to(address);
+        self
+    }
+
+    /// Adds a `To` header and stores the recipient address
+    pub fn add_to<A: ToMailbox>(&mut self, address: A) {
+        let mailbox = address.to_mailbox();
+        self.to.push(mailbox.address.clone());
+        self.to_header.push(Address::Mailbox(mailbox));
+    }
+
+    /// Adds a `Cc` header and stores the recipient address
+    pub fn cc<A: ToMailbox>(mut self, address: A) -> EmailBuilder {
+        self.add_cc(address);
+        self
+    }
+
+    /// Adds a `Cc` header and stores the recipient address
+    pub fn add_cc<A: ToMailbox>(&mut self, address: A) {
+        let mailbox = address.to_mailbox();
+        self.to.push(mailbox.address.clone());
+        self.cc_header.push(Address::Mailbox(mailbox));
+    }
+
+    /// Adds a `Reply-To` header
+    pub fn reply_to<A: ToMailbox>(mut self, address: A) -> EmailBuilder {
+        self.add_reply_to(address);
+        self
+    }
+
+    /// Adds a `Reply-To` header
+    pub fn add_reply_to<A: ToMailbox>(&mut self, address: A) {
+        let mailbox = address.to_mailbox();
+        self.reply_to_header.push(Address::Mailbox(mailbox));
+    }
+
+    /// Adds a `Sender` header
+    pub fn sender<A: ToMailbox>(mut self, address: A) -> EmailBuilder {
+        self.set_sender(address);
+        self
+    }
+
+    /// Adds a `Sender` header
+    pub fn set_sender<A: ToMailbox>(&mut self, address: A) {
+        let mailbox = address.to_mailbox();
+        self.from = Some(mailbox.address.clone());
+        self.sender_header = Some(mailbox);
+    }
+
+    /// Adds a `Subject` header
+    pub fn subject(mut self, subject: &str) -> EmailBuilder {
+        self.set_subject(subject);
+        self
+    }
+
+    /// Adds a `Subject` header
+    pub fn set_subject(&mut self, subject: &str) {
+        self.message.add_header(("Subject", subject));
+    }
+
+    /// Adds a `Date` header with the given date
+    pub fn date(mut self, date: &Tm) -> EmailBuilder {
+        self.set_date(date);
+        self
+    }
+
+    /// Adds a `Date` header with the given date
+    pub fn set_date(&mut self, date: &Tm) {
+        self.message.add_header(("Date", Tm::rfc822z(date).to_string().as_ref()));
+        self.date_issued = true;
+    }
+
+    /// Set the message type
+    pub fn message_type(mut self, message_type: MimeMultipartType) -> EmailBuilder {
+        self.set_message_type(message_type);
+        self
+    }
+
+    /// Set the message type
+    pub fn set_message_type(&mut self, message_type: MimeMultipartType) {
+        self.message.set_message_type(message_type);
+    }
+
+    /// Adds a child
+    pub fn child(mut self, child: MimeMessage) -> EmailBuilder {
+        self.add_child(child);
+        self
+    }
+
+    /// Adds a child
+    pub fn add_child(&mut self, child: MimeMessage) {
+        self.message.add_child(child);
+    }
+
+    /// Sets the email body to plain text content
+    pub fn text(mut self, body: &str) -> EmailBuilder {
+        self.set_text(body);
+        self
+    }
+
+    /// Sets the email body to plain text content
+    pub fn set_text(&mut self, body: &str) {
+        self.message.set_body(body);
+        self.message
+            .add_header(("Content-Type", format!("{}", mime!(Text/Plain; Charset=Utf8)).as_ref()));
+    }
+
+    /// Sets the email body to HTML content
+    pub fn html(mut self, body: &str) -> EmailBuilder {
+        self.set_html(body);
+        self
+    }
+
+    /// Sets the email body to HTML content
+    pub fn set_html(&mut self, body: &str) {
+        self.message.set_body(body);
+        self.message
+            .add_header(("Content-Type", format!("{}", mime!(Text/Html; Charset=Utf8)).as_ref()));
+    }
+
+    /// Sets the email content
+    pub fn alternative(mut self, body_html: &str, body_text: &str) -> EmailBuilder {
+        self.set_alternative(body_html, body_text);
+        self
+    }
+
+    /// Sets the email content
+    pub fn set_alternative(&mut self, body_html: &str, body_text: &str) {
+        let mut alternate = PartBuilder::new();
+        alternate.set_message_type(MimeMultipartType::Alternative);
+
+        let text = PartBuilder::new()
+            .body(body_text)
+            .header(("Content-Type", format!("{}", mime!(Text/Plain; Charset=Utf8)).as_ref()))
+            .build();
+
+        let html = PartBuilder::new()
+            .body(body_html)
+            .header(("Content-Type", format!("{}", mime!(Text/Html; Charset=Utf8)).as_ref()))
+            .build();
+
+        alternate.add_child(text);
+        alternate.add_child(html);
+
+        self.set_message_type(MimeMultipartType::Mixed);
+        self.add_child(alternate.build());
+    }
+
+    /// Builds the Email
+    pub fn build(mut self) -> Result<Email, Error> {
+        if self.from.is_none() {
+            return Err(Error::MissingFrom);
+        }
+        if self.to.is_empty() {
+            return Err(Error::MissingTo);
+        }
+        // If there are multiple addresses in "From", the "Sender" is required.
+        if self.from_header.len() >= 2 && self.sender_header.is_none() {
+            // So, we must find something to put as Sender.
+            for possible_sender in self.from_header.iter() {
+                // Only a mailbox can be used as sender, not Address::Group.
+                if let &Address::Mailbox(ref mbx) = possible_sender {
+                    self.sender_header = Some(mbx.clone());
+                    break;
+                }
+            }
+            // Address::Group is not yet supported, so the line below will never panic.
+            // If groups are supported one day, add another Error for this case
+            //  and return it here, if sender_header is still None at this point.
+            assert!(self.sender_header.is_some());
+        }
+        // Add the sender header, if any.
+        if let Some(v) = self.sender_header {
+            self.message.add_header(("Sender", v.to_string().as_ref()));
+        }
+        // Add the collected addresses as mailbox-list all at once.
+        // The unwraps are fine because the conversions for Vec<Address> never errs.
+        self.message.add_header(Header::new_with_value("To".into(), self.to_header).unwrap());
+        self.message.add_header(Header::new_with_value("From".into(), self.from_header).unwrap());
+        if !self.cc_header.is_empty() {
+            self.message.add_header(Header::new_with_value("Cc".into(), self.cc_header).unwrap());
+        }
+        if !self.reply_to_header.is_empty() {
+            self.message.add_header(Header::new_with_value("Reply-To".into(),
+                                                           self.reply_to_header)
+                .unwrap());
+        }
+
+
+        if !self.date_issued {
+            self.message.add_header(("Date", Tm::rfc822z(&now()).to_string().as_ref()));
+        }
+
+        self.message.add_header(("MIME-Version", "1.0"));
+
+        let message_id = Uuid::new_v4();
+
+        if let Ok(header) = Header::new_with_value("Message-ID".to_string(),
+                                                   format!("<{}.lettre@localhost>", message_id)) {
+            self.message.add_header(header)
+        }
+
+        Ok(Email {
+            message: self.message.build(),
+            envelope: Envelope {
+                to: self.to,
+                from: self.from.unwrap(),
+            },
+            message_id: message_id,
+        })
+    }
+}
+
+/// Email sendable by an SMTP client
+pub trait SendableEmail {
+    /// From address
+    fn from_address(&self) -> String;
+    /// To addresses
+    fn to_addresses(&self) -> Vec<String>;
+    /// Message content
+    fn message(&self) -> String;
+    /// Message ID
+    fn message_id(&self) -> String;
+}
+
+/// Minimal email structure
+pub struct SimpleSendableEmail {
+    /// From address
+    from: String,
+    /// To addresses
+    to: Vec<String>,
+    /// Message
+    message: String,
+}
+
+impl SimpleSendableEmail {
+    /// Returns a new email
+    pub fn new(from_address: &str, to_address: Vec<String>, message: &str) -> SimpleSendableEmail {
+        SimpleSendableEmail {
+            from: from_address.to_string(),
+            to: to_address,
+            message: message.to_string(),
+        }
+    }
+}
+
+impl SendableEmail for SimpleSendableEmail {
+    fn from_address(&self) -> String {
+        self.from.clone()
+    }
+
+    fn to_addresses(&self) -> Vec<String> {
+        self.to.clone()
+    }
+
+    fn message(&self) -> String {
+        self.message.clone()
+    }
+
+    fn message_id(&self) -> String {
+        format!("{}", Uuid::new_v4())
+    }
+}
+
+impl SendableEmail for Email {
+    fn to_addresses(&self) -> Vec<String> {
+        self.envelope.to.clone()
+    }
+
+    fn from_address(&self) -> String {
+        self.envelope.from.clone()
+    }
+
+    fn message(&self) -> String {
+        format!("{}", self)
+    }
+
+    fn message_id(&self) -> String {
+        format!("{}", self.message_id)
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use email_format::{Header, MimeMessage};
+
+    use super::{Email, EmailBuilder, Envelope, SendableEmail};
+    use time::now;
+
+    use uuid::Uuid;
+
+    #[test]
+    fn test_email_display() {
+        let current_message = Uuid::new_v4();
+
+        let mut email = Email {
+            message: MimeMessage::new_blank_message(),
+            envelope: Envelope {
+                to: vec![],
+                from: "".to_string(),
+            },
+            message_id: current_message,
+        };
+
+        email.message.headers.insert(Header::new_with_value("Message-ID".to_string(),
+                                                            format!("<{}@rust-smtp>",
+                                                                    current_message))
+            .unwrap());
+
+        email.message
+            .headers
+            .insert(Header::new_with_value("To".to_string(), "to@example.com".to_string())
+                .unwrap());
+
+        email.message.body = "body".to_string();
+
+        assert_eq!(format!("{}", email),
+                   format!("Message-ID: <{}@rust-smtp>\r\nTo: to@example.com\r\n\r\nbody\r\n",
+                           current_message));
+        assert_eq!(current_message.to_string(), email.message_id());
+    }
+
+    #[test]
+    fn test_multiple_from() {
+        let email_builder = EmailBuilder::new();
+        let date_now = now();
+        let email = email_builder.to("anna@example.com")
+            .from("dieter@example.com")
+            .from("joachim@example.com")
+            .date(&date_now)
+            .subject("Invitation")
+            .body("We invite you!")
+            .build()
+            .unwrap();
+        assert_eq!(format!("{}", email),
+                   format!("Date: {}\r\nSubject: Invitation\r\nSender: \
+                            <dieter@example.com>\r\nTo: <anna@example.com>\r\nFrom: \
+                            <dieter@example.com>, <joachim@example.com>\r\nMIME-Version: \
+                            1.0\r\nMessage-ID: <{}.lettre@localhost>\r\n\r\nWe invite you!\r\n",
+                           date_now.rfc822z(),
+                           email.message_id()));
+    }
+
+    #[test]
+    fn test_simple_email_builder() {
+        let email_builder = EmailBuilder::new();
+        let date_now = now();
+
+        let email = email_builder.to("user@localhost")
+            .from("user@localhost")
+            .cc(("cc@localhost", "Alias"))
+            .reply_to("reply@localhost")
+            .sender("sender@localhost")
+            .body("Hello World!")
+            .date(&date_now)
+            .subject("Hello")
+            .header(("X-test", "value"))
+            .build()
+            .unwrap();
+
+        assert_eq!(format!("{}", email),
+                   format!("Date: {}\r\nSubject: Hello\r\nX-test: value\r\nSender: \
+                            <sender@localhost>\r\nTo: <user@localhost>\r\nFrom: \
+                            <user@localhost>\r\nCc: \"Alias\" <cc@localhost>\r\nReply-To: \
+                            <reply@localhost>\r\nMIME-Version: 1.0\r\nMessage-ID: \
+                            <{}.lettre@localhost>\r\n\r\nHello World!\r\n",
+                           date_now.rfc822z(),
+                           email.message_id()));
+    }
+
+    #[test]
+    fn test_email_sendable() {
+        let email_builder = EmailBuilder::new();
+        let date_now = now();
+
+        let email = email_builder.to("user@localhost")
+            .from("user@localhost")
+            .cc(("cc@localhost", "Alias"))
+            .reply_to("reply@localhost")
+            .sender("sender@localhost")
+            .body("Hello World!")
+            .date(&date_now)
+            .subject("Hello")
+            .header(("X-test", "value"))
+            .build()
+            .unwrap();
+
+        assert_eq!(email.from_address(), "sender@localhost".to_string());
+        assert_eq!(email.to_addresses(),
+                   vec!["user@localhost".to_string(), "cc@localhost".to_string()]);
+        assert_eq!(email.message(), format!("{}", email));
+    }
+
+}

src/lib.rs

@@ -1,133 +1,177 @@
-//! # Rust SMTP client
+//! Lettre is a mailer written in Rust. It provides a simple email builder and several transports.
 //!
-//! This client should tend to follow [RFC 5321](https://tools.ietf.org/html/rfc5321), but is still
-//! a work in progress. It is designed to efficiently send emails from an application to a
-//! relay email server, as it relies as much as possible on the relay server for sanity and RFC
+//! ## Overview
+//!
+//! This mailer is divided into:
+//!
+//! * An `email` part: builds the email message
+//! * A `transport` part: contains the available transports for your emails. To be sendable, the
+//!   emails have to implement `SendableEmail`.
+//!
+//! ## Creating messages
+//!
+//! The `email` part builds email messages. For now, it does not support attachments.
+//! An email is built using an `EmailBuilder`. The simplest email could be:
+//!
+//! ```rust
+//! use lettre::email::EmailBuilder;
+//!
+//! // Create an email
+//! let email = EmailBuilder::new()
+//!     // Addresses can be specified by the tuple (email, alias)
+//!     .to(("user@example.org", "Firstname Lastname"))
+//!     // ... or by an address only
+//!     .from("user@example.com")
+//!     .subject("Hi, Hello world")
+//!     .text("Hello world.")
+//!     .build();
+//!
+//! assert!(email.is_ok());
+//! ```
+//!
+//! When the `build` method is called, the `EmailBuilder` will add the missing headers (like
+//! `Message-ID` or `Date`) and check for missing necessary ones (like `From` or `To`). It will
+//! then generate an `Email` that can be sent.
+//!
+//! The `text()` method will create a plain text email, while the `html()` method will create an
+//! HTML email. You can use the `alternative()` method to provide both versions, using plain text
+//! as fallback for the HTML version.
+//!
+//! Below is a more complete example, not using method chaining:
+//!
+//! ```rust
+//! use lettre::email::EmailBuilder;
+//!
+//! let mut builder = EmailBuilder::new();
+//! builder.add_to(("user@example.org", "Alias name"));
+//! builder.add_cc(("user@example.net", "Alias name"));
+//! builder.add_from("no-reply@example.com");
+//! builder.add_from("no-reply@example.eu");
+//! builder.set_sender("no-reply@example.com");
+//! builder.set_subject("Hello world");
+//! builder.set_alternative("<h2>Hi, Hello world.</h2>", "Hi, Hello world.");
+//! builder.add_reply_to("contact@example.com");
+//! builder.add_header(("X-Custom-Header", "my header"));
+//!
+//! let email = builder.build();
+//! assert!(email.is_ok());
+//! ```
+//!
+//! See the `EmailBuilder` documentation for a complete list of methods.
+//!
+//! ## Sending messages
+//!
+//! The following sections describe the available transport methods to handle emails.
+//!
+//! * The `SmtpTransport` uses the SMTP protocol to send the message over the network. It is
+//!   the prefered way of sending emails.
+//! * The `FileTransport` creates a file containing the email content to be sent. It can be used
+//!   for debugging or if you want to keep all sent emails.
+//! * The `StubTransport` is useful for debugging, and only prints the content of the email in the
+//!   logs.
+//!
+//! ### SMTP transport
+//!
+//! This SMTP follows [RFC
+//! 5321](https://tools.ietf.org/html/rfc5321), but is still
+//! a work in progress. It is designed to efficiently send emails from an
+//! application to a
+//! relay email server, as it relies as much as possible on the relay server
+//! for sanity and RFC
 //! compliance checks.
 //!
 //! It implements the following extensions:
 //!
 //! * 8BITMIME ([RFC 6152](https://tools.ietf.org/html/rfc6152))
-//! * AUTH ([RFC 4954](http://tools.ietf.org/html/rfc4954)) with PLAIN and CRAM-MD5 mecanisms
+//! * AUTH ([RFC 4954](http://tools.ietf.org/html/rfc4954)) with PLAIN and
+//! CRAM-MD5 mechanisms
 //! * STARTTLS ([RFC 2487](http://tools.ietf.org/html/rfc2487))
-//!
-//! It will eventually implement the following extensions:
-//!
 //! * SMTPUTF8 ([RFC 6531](http://tools.ietf.org/html/rfc6531))
 //!
-//! ## Architecture
-//!
-//! This client is divided into three main parts:
-//!
-//! * client: a low level SMTP client providing all SMTP commands
-//! * sender: a high level SMTP client providing an easy method to send emails
-//! * email: generates the email to be sent with the sender
-//!
-//! ## Usage
-//!
-//! ### Simple example
+//! #### Simple example
 //!
 //! This is the most basic example of usage:
 //!
-//! ```rust,no_run
-//! use smtp::sender::{Sender, SenderBuilder};
-//! use smtp::email::EmailBuilder;
+//! ```rust
+//! use lettre::transport::smtp::{SmtpTransport, SmtpTransportBuilder};
+//! use lettre::email::EmailBuilder;
+//! use lettre::transport::EmailTransport;
 //!
-//! // Create an email
 //! let email = EmailBuilder::new()
-//!     // Addresses can be specified by the couple (email, alias)
-//!     .to(("user@example.org", "Firstname Lastname"))
-//!     // ... or by an address only
-//!     .from("user@example.com")
-//!     .subject("Hi, Hello world")
-//!     .body("Hello world.")
-//!     .build();
+//!                     .to("root@localhost")
+//!                     .from("user@localhost")
+//!                     .body("Hello World!")
+//!                     .subject("Hello")
+//!                     .build()
+//!                     .unwrap();
 //!
 //! // Open a local connection on port 25
-//! let mut sender = SenderBuilder::localhost().unwrap().build();
+//! let mut mailer =
+//! SmtpTransportBuilder::localhost().unwrap().build();
 //! // Send the email
-//! let result = sender.send(email);
+//! let result = mailer.send(email);
 //!
 //! assert!(result.is_ok());
 //! ```
 //!
-//! ### Complete example
+//! #### Complete example
 //!
 //! ```rust,no_run
-//! use smtp::sender::{Sender, SenderBuilder};
-//! use smtp::email::EmailBuilder;
-//! use smtp::authentication::Mecanism;
-//! use smtp::SUBMISSION_PORT;
+//! use lettre::email::EmailBuilder;
+//! use lettre::transport::smtp::{SecurityLevel, SmtpTransport,
+//! SmtpTransportBuilder};
+//! use lettre::transport::smtp::authentication::Mechanism;
+//! use lettre::transport::smtp::SUBMISSION_PORT;
+//! use lettre::transport::EmailTransport;
 //!
-//! let mut builder = EmailBuilder::new();
-//! builder = builder.to(("user@example.org", "Alias name"));
-//! builder = builder.cc(("user@example.net", "Alias name"));
-//! builder = builder.from("no-reply@example.com");
-//! builder = builder.from("no-reply@example.eu");
-//! builder = builder.sender("no-reply@example.com");
-//! builder = builder.subject("Hello world");
-//! builder = builder.body("Hi, Hello world.");
-//! builder = builder.reply_to("contact@example.com");
-//! builder = builder.add_header(("X-Custom-Header", "my header"));
-//!
-//! let email = builder.build();
+//! let email = EmailBuilder::new()
+//!                     .to("root@localhost")
+//!                     .from("user@localhost")
+//!                     .body("Hello World!")
+//!                     .subject("Hello")
+//!                     .build()
+//!                     .unwrap();
 //!
 //! // Connect to a remote server on a custom port
-//! let mut sender = SenderBuilder::new(("server.tld", SUBMISSION_PORT)).unwrap()
+//! let mut mailer = SmtpTransportBuilder::new(("server.tld",
+//! SUBMISSION_PORT)).unwrap()
 //!     // Set the name sent during EHLO/HELO, default is `localhost`
 //!     .hello_name("my.hostname.tld")
 //!     // Add credentials for authentication
 //!     .credentials("username", "password")
-//!     // Use TLS with STARTTLS, you can also specify a specific SSL context
-//!     // with `.ssl_context(context)`
-//!     .starttls()
-//!     // Configure accepted authetication mecanisms
-//!     .authentication_mecanisms(vec![Mecanism::CramMd5])
+//!     // Specify a TLS security level. You can also specify an SslContext with
+//!     // .ssl_context(SslContext::Ssl23)
+//!     .security_level(SecurityLevel::AlwaysEncrypt)
+//!     // Enable SMTPUTF8 if the server supports it
+//!     .smtp_utf8(true)
+//!     // Configure expected authentication mechanism
+//!     .authentication_mechanism(Mechanism::CramMd5)
 //!     // Enable connection reuse
-//!     .enable_connection_reuse(true).build();
+//!     .connection_reuse(true).build();
 //!
-//! let result_1 = sender.send(email.clone());
+//! let result_1 = mailer.send(email.clone());
 //! assert!(result_1.is_ok());
 //!
 //! // The second email will use the same connection
-//! let result_2 = sender.send(email);
+//! let result_2 = mailer.send(email);
 //! assert!(result_2.is_ok());
 //!
-//! // Explicitely close the SMTP transaction as we enabled connection reuse
-//! sender.close();
+//! // Explicitly close the SMTP transaction as we enabled connection reuse
+//! mailer.close();
 //! ```
 //!
-//! ### Using the client directly
+//! #### Lower level
 //!
-//! If you just want to send an email without using `Email` to provide headers:
+//! You can also send commands, here is a simple email transaction without
+//! error handling:
 //!
-//! ```rust,no_run
-//! use smtp::sender::{Sender, SenderBuilder};
-//! use smtp::email::SimpleSendableEmail;
-//!
-//! // Create a minimal email
-//! let email = SimpleSendableEmail::new(
-//!     "test@example.com",
-//!     "test@example.org",
-//!     "Hello world !"
-//! );
-//!
-//! let mut sender = SenderBuilder::localhost().unwrap().build();
-//! let result = sender.send(email);
-//! assert!(result.is_ok());
-//! ```
-//!
-//! ### Lower level
-//!
-//! You can also send commands, here is a simple email transaction without error handling:
-//!
-//! ```rust,no_run
-//! use smtp::client::Client;
-//! use smtp::SMTP_PORT;
-//! use smtp::client::net::NetworkStream;
+//! ```rust
+//! use lettre::transport::smtp::SMTP_PORT;
+//! use lettre::transport::smtp::client::Client;
+//! use lettre::transport::smtp::client::net::NetworkStream;
 //!
 //! let mut email_client: Client<NetworkStream> = Client::new();
-//! let _ = email_client.connect(&("localhost", SMTP_PORT));
+//! let _ = email_client.connect(&("localhost", SMTP_PORT), None);
 //! let _ = email_client.ehlo("my_hostname");
 //! let _ = email_client.mail("user@example.com", None);
 //! let _ = email_client.rcpt("user@example.org");
@@ -135,12 +179,83 @@
 //! let _ = email_client.message("Test email");
 //! let _ = email_client.quit();
 //! ```
+//!
+//! ### Stub transport
+//!
+//! The stub transport only logs message envelope and drops the content. It can be useful for
+//! testing purposes.
+//!
+//! ```rust
+//! use lettre::transport::stub::StubEmailTransport;
+//! use lettre::transport::EmailTransport;
+//! use lettre::email::EmailBuilder;
+//!
+//! let email = EmailBuilder::new()
+//!                     .to("root@localhost")
+//!                     .from("user@localhost")
+//!                     .body("Hello World!")
+//!                     .subject("Hello")
+//!                     .build()
+//!                     .unwrap();
+//!
+//! let mut sender = StubEmailTransport;
+//! let result = sender.send(email);
+//! assert!(result.is_ok());
+//! ```
+//!
+//! Will log the line:
+//!
+//! ```text
+//! b7c211bc-9811-45ce-8cd9-68eab575d695: from=<user@localhost> to=<root@localhost>
+//! ```
+//!
+//! ### File transport
+//!
+//! The file transport writes the emails to the given directory. The name of the file will be
+//! `message_id.txt`.
+//! It can be useful for testing purposes, or if you want to keep track of sent messages.
+//!
+//! ```rust
+//! use std::env::temp_dir;
+//!
+//! use lettre::transport::file::FileEmailTransport;
+//! use lettre::transport::EmailTransport;
+//! use lettre::email::{EmailBuilder, SendableEmail};
+//!
+//! // Write to the local temp directory
+//! let mut sender = FileEmailTransport::new(temp_dir());
+//! let email = EmailBuilder::new()
+//!                 .to("root@localhost")
+//!                 .from("user@localhost")
+//!                 .body("Hello World!")
+//!                 .subject("Hello")
+//!                 .build()
+//!                 .unwrap();
+//!
+//! let result = sender.send(email);
+//! assert!(result.is_ok());
+//! ```
+//! Example result in `/tmp/b7c211bc-9811-45ce-8cd9-68eab575d695.txt`:
+//!
+//! ```text
+//! b7c211bc-9811-45ce-8cd9-68eab575d695: from=<user@localhost> to=<root@localhost>
+//! To: <root@localhost>
+//! From: <user@localhost>
+//! Subject: Hello
+//! Date: Sat, 31 Oct 2015 13:42:19 +0100
+//! Message-ID: <b7c211bc-9811-45ce-8cd9-68eab575d695.lettre@localhost>
+//!
+//! Hello World!
+//! ```
 
-#![deny(missing_docs)]
+
+#![deny(missing_docs, unsafe_code, unstable_features)]
 
 #[macro_use]
 extern crate log;
-extern crate rustc_serialize as serialize;
+#[macro_use]
+extern crate mime;
+extern crate rustc_serialize;
 extern crate crypto;
 extern crate time;
 extern crate uuid;
@@ -148,39 +263,5 @@ extern crate email as email_format;
 extern crate bufstream;
 extern crate openssl;
 
-mod extension;
-pub mod client;
-pub mod sender;
-pub mod response;
-pub mod error;
-pub mod authentication;
+pub mod transport;
 pub mod email;
-
-// Registrated port numbers:
-// https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml
-
-/// Default smtp port
-pub static SMTP_PORT: u16 = 25;
-
-/// Default smtps port
-pub static SMTPS_PORT: u16 = 465;
-
-/// Default submission port
-pub static SUBMISSION_PORT: u16 = 587;
-
-// Useful strings and characters
-
-/// The word separator for SMTP transactions
-pub static SP: &'static str = " ";
-
-/// The line ending for SMTP transactions (carriage return + line feed)
-pub static CRLF: &'static str = "\r\n";
-
-/// Colon
-pub static COLON: &'static str = ":";
-
-/// The ending of message content
-pub static MESSAGE_ENDING: &'static str = "\r\n.\r\n";
-
-/// NUL unicode character
-pub static NUL: &'static str = "\0";

src/sender.rs

@@ -1,298 +0,0 @@
-//! Sends an email using the client
-
-use std::string::String;
-use std::net::{SocketAddr, ToSocketAddrs};
-
-use openssl::ssl::{SslMethod, SslContext};
-
-use SMTP_PORT;
-use extension::{Extension, ServerInfo};
-use error::{SmtpResult, Error};
-use email::SendableEmail;
-use client::Client;
-use authentication::Mecanism;
-
-/// Contains client configuration
-pub struct SenderBuilder {
-    /// Maximum connection reuse
-    ///
-    /// Zero means no limitation
-    connection_reuse_count_limit: u16,
-    /// Enable connection reuse
-    enable_connection_reuse: bool,
-    /// Name sent during HELO or EHLO
-    hello_name: String,
-    /// Credentials
-    credentials: Option<(String, String)>,
-    /// Socket we are connecting to
-    server_addr: SocketAddr,
-    /// SSL contexyt to use
-    ssl_context: Option<SslContext>,
-    /// List of authentication mecanism, sorted by priority
-    authentication_mecanisms: Vec<Mecanism>,
-}
-
-/// Builder for the SMTP Sender
-impl SenderBuilder {
-    /// Creates a new local SMTP client
-    pub fn new<A: ToSocketAddrs>(addr: A) -> Result<SenderBuilder, Error> {
-        let mut addresses = try!(addr.to_socket_addrs());
-
-        match addresses.next() {
-            Some(addr) => Ok(SenderBuilder {
-                server_addr: addr,
-                ssl_context: None,
-                credentials: None,
-                connection_reuse_count_limit: 100,
-                enable_connection_reuse: false,
-                hello_name: "localhost".to_string(),
-                authentication_mecanisms: vec![Mecanism::CramMd5, Mecanism::Plain],
-            }),
-            None => Err(From::from("Could nor resolve hostname")),
-        }
-    }
-
-    /// Creates a new local SMTP client to port 25
-    pub fn localhost() -> Result<SenderBuilder, Error> {
-        SenderBuilder::new(("localhost", SMTP_PORT))
-    }
-
-    /// Use STARTTLS with a specific context
-    pub fn ssl_context(mut self, ssl_context: SslContext) -> SenderBuilder {
-        self.ssl_context = Some(ssl_context);
-        self
-    }
-
-    /// Require SSL/TLS using STARTTLS
-    pub fn starttls(self) -> SenderBuilder {
-        self.ssl_context(SslContext::new(SslMethod::Tlsv1).unwrap())
-    }
-
-    /// Set the name used during HELO or EHLO
-    pub fn hello_name(mut self, name: &str) -> SenderBuilder {
-        self.hello_name = name.to_string();
-        self
-    }
-
-    /// Enable connection reuse
-    pub fn enable_connection_reuse(mut self, enable: bool) -> SenderBuilder {
-        self.enable_connection_reuse = enable;
-        self
-    }
-
-    /// Set the maximum number of emails sent using one connection
-    pub fn connection_reuse_count_limit(mut self, limit: u16) -> SenderBuilder {
-        self.connection_reuse_count_limit = limit;
-        self
-    }
-
-    /// Set the client credentials
-    pub fn credentials(mut self, username: &str, password: &str) -> SenderBuilder {
-        self.credentials = Some((username.to_string(), password.to_string()));
-        self
-    }
-
-    /// Set the authentication mecanisms
-    pub fn authentication_mecanisms(mut self, mecanisms: Vec<Mecanism>) -> SenderBuilder {
-        self.authentication_mecanisms = mecanisms;
-        self
-    }
-
-    /// Build the SMTP client
-    ///
-    /// It does not connects to the server, but only creates the `Sender`
-    pub fn build(self) -> Sender {
-        Sender::new(self)
-    }
-}
-
-/// Represents the state of a client
-#[derive(Debug)]
-struct State {
-    /// Panic state
-    pub panic: bool,
-    /// Connection reuse counter
-    pub connection_reuse_count: u16,
-}
-
-/// Structure that implements the high level SMTP client
-pub struct Sender {
-    /// Information about the server
-    /// Value is None before HELO/EHLO
-    server_info: Option<ServerInfo>,
-    /// Sender variable states
-    state: State,
-    /// Information about the client
-    client_info: SenderBuilder,
-    /// Low level client
-    client: Client,
-}
-
-macro_rules! try_smtp (
-    ($err: expr, $client: ident) => ({
-        match $err {
-            Ok(val) => val,
-            Err(err) => {
-                if !$client.state.panic {
-                    $client.state.panic = true;
-                    $client.reset();
-                }
-                return Err(err)
-            },
-        }
-    })
-);
-
-impl Sender {
-    /// Creates a new SMTP client
-    ///
-    /// It does not connects to the server, but only creates the `Sender`
-    pub fn new(builder: SenderBuilder) -> Sender {
-
-        let client = Client::new();
-
-        Sender {
-            client: client,
-            server_info: None,
-            client_info: builder,
-            state: State {
-                panic: false,
-                connection_reuse_count: 0,
-            },
-        }
-    }
-
-    /// Reset the client state
-    fn reset(&mut self) {
-        // Close the SMTP transaction if needed
-        self.close();
-
-        // Reset the client state
-        self.server_info = None;
-        self.state.panic = false;
-        self.state.connection_reuse_count = 0;
-    }
-
-    /// Closes the inner connection
-    pub fn close(&mut self) {
-        self.client.close();
-    }
-
-    /// Gets the EHLO response and updates server information
-    pub fn get_ehlo(&mut self) -> SmtpResult {
-        // Extended Hello
-        let ehlo_response = try_smtp!(self.client.ehlo(&self.client_info.hello_name), self);
-
-        self.server_info = Some(try_smtp!(ServerInfo::from_response(&ehlo_response), self));
-
-        // Print server information
-        debug!("server {}", self.server_info.as_ref().unwrap());
-
-        Ok(ehlo_response)
-    }
-
-    /// Sends an email
-    pub fn send<T: SendableEmail>(&mut self, email: T) -> SmtpResult {
-        // Check if the connection is still available
-        if self.state.connection_reuse_count > 0 {
-            if !self.client.is_connected() {
-                self.reset();
-            }
-        }
-
-        // If there is a usable connection, test if the server answers and hello has been sent
-        if self.state.connection_reuse_count == 0 {
-            try!(self.client.connect(&self.client_info.server_addr));
-
-            // Log the connection
-            info!("connection established to {}", self.client_info.server_addr);
-
-            try!(self.get_ehlo());
-
-            if self.client_info.ssl_context.is_some() {
-                try_smtp!(self.client.starttls(), self);
-
-                try!(self.client
-                         .upgrade_tls_stream(self.client_info.ssl_context.as_ref().unwrap()));
-
-                try!(self.get_ehlo());
-            }
-
-            if self.client_info.credentials.is_some() && self.state.connection_reuse_count == 0 {
-                let (username, password) = self.client_info.credentials.clone().unwrap();
-
-                let mut found = false;
-
-                for mecanism in self.client_info.authentication_mecanisms.clone() {
-                    if self.server_info.as_ref().unwrap().supports_auth_mecanism(mecanism) {
-                        found = true;
-                        let result = self.client.auth(mecanism, &username, &password);
-                        try_smtp!(result, self);
-                    }
-                }
-
-                if !found {
-                    debug!("No supported authentication mecanisms available");
-                }
-            }
-        }
-
-        let current_message = try!(email.message_id().ok_or("Missing Message-ID"));
-        let from_address = try!(email.from_address().ok_or("Missing From address"));
-        let to_addresses = try!(email.to_addresses().ok_or("Missing To address"));
-        let message = try!(email.message().ok_or("Missing message"));
-
-        // Mail
-        let mail_options = match self.server_info
-                                     .as_ref()
-                                     .unwrap()
-                                     .supports_feature(&Extension::EightBitMime) {
-            true => Some("BODY=8BITMIME"),
-            false => None,
-        };
-
-        try_smtp!(self.client.mail(&from_address, mail_options), self);
-
-        // Log the mail command
-        info!("{}: from=<{}>", current_message, from_address);
-
-        // Recipient
-        for to_address in to_addresses.iter() {
-            try_smtp!(self.client.rcpt(&to_address), self);
-            // Log the rcpt command
-            info!("{}: to=<{}>", current_message, to_address);
-        }
-
-        // Data
-        try_smtp!(self.client.data(), self);
-
-        // Message content
-        let result = self.client.message(&message);
-
-        if result.is_ok() {
-            // Increment the connection reuse counter
-            self.state.connection_reuse_count = self.state.connection_reuse_count + 1;
-
-            // Log the message
-            info!("{}: conn_use={}, size={}, status=sent ({})",
-                  current_message,
-                  self.state.connection_reuse_count,
-                  message.len(),
-                  result.as_ref()
-                        .ok()
-                        .unwrap()
-                        .message()
-                        .iter()
-                        .next()
-                        .unwrap_or(&"no response".to_string()));
-        }
-
-        // Test if we can reuse the existing connection
-        if (!self.client_info.enable_connection_reuse) ||
-           (self.state.connection_reuse_count >= self.client_info.connection_reuse_count_limit) {
-            self.reset();
-        }
-
-        result
-    }
-}

src/transport/file/error.rs

@@ -0,0 +1,54 @@
+//! Error and result type for file transport
+
+
+use self::Error::*;
+use std::error::Error as StdError;
+use std::fmt;
+use std::fmt::{Display, Formatter};
+use std::io;
+
+/// An enum of all error kinds.
+#[derive(Debug)]
+pub enum Error {
+    /// Internal client error
+    Client(&'static str),
+    /// IO error
+    Io(io::Error),
+}
+
+impl Display for Error {
+    fn fmt(&self, fmt: &mut Formatter) -> Result<(), fmt::Error> {
+        fmt.write_str(self.description())
+    }
+}
+
+impl StdError for Error {
+    fn description(&self) -> &str {
+        match *self {
+            Client(_) => "an unknown error occured",
+            Io(_) => "an I/O error occured",
+        }
+    }
+
+    fn cause(&self) -> Option<&StdError> {
+        match *self {
+            Io(ref err) => Some(&*err as &StdError),
+            _ => None,
+        }
+    }
+}
+
+impl From<io::Error> for Error {
+    fn from(err: io::Error) -> Error {
+        Io(err)
+    }
+}
+
+impl From<&'static str> for Error {
+    fn from(string: &'static str) -> Error {
+        Client(string)
+    }
+}
+
+/// SMTP result type
+pub type FileResult = Result<(), Error>;

src/transport/file/mod.rs

@@ -0,0 +1,51 @@
+//! This transport creates a file for each email, containing the envelope information and the email
+//! itself.
+
+use email::SendableEmail;
+use std::fs::File;
+use std::io::prelude::*;
+use std::path::{Path, PathBuf};
+
+use transport::EmailTransport;
+use transport::file::error::FileResult;
+
+pub mod error;
+
+/// Writes the content and the envelope information to a file
+pub struct FileEmailTransport {
+    path: PathBuf,
+}
+
+impl FileEmailTransport {
+    /// Creates a new transport to the given directory
+    pub fn new<P: AsRef<Path>>(path: P) -> FileEmailTransport {
+        let mut path_buf = PathBuf::new();
+        path_buf.push(path);
+        FileEmailTransport { path: path_buf }
+    }
+}
+
+impl EmailTransport<FileResult> for FileEmailTransport {
+    fn send<T: SendableEmail>(&mut self, email: T) -> FileResult {
+        let mut file = self.path.clone();
+        file.push(format!("{}.txt", email.message_id()));
+
+        let mut f = try!(File::create(file.as_path()));
+
+        let log_line = format!("{}: from=<{}> to=<{}>\n",
+                               email.message_id(),
+                               email.from_address(),
+                               email.to_addresses().join("> to=<"));
+
+        try!(f.write_all(log_line.as_bytes()));
+        try!(f.write_all(email.message().clone().as_bytes()));
+
+        info!("{} status=<written>", log_line);
+
+        Ok(())
+    }
+
+    fn close(&mut self) {
+        ()
+    }
+}

src/transport/mod.rs

@@ -0,0 +1,14 @@
+//! Represents an Email transport
+pub mod smtp;
+pub mod stub;
+pub mod file;
+
+use email::SendableEmail;
+
+/// Transport method for emails
+pub trait EmailTransport<U> {
+    /// Sends the email
+    fn send<T: SendableEmail>(&mut self, email: T) -> U;
+    /// Close the transport explicitly
+    fn close(&mut self);
+}

src/transport/smtp/authentication.rs

@@ -0,0 +1,111 @@
+//! Provides authentication mechanisms
+
+use crypto::hmac::Hmac;
+use crypto::mac::Mac;
+use crypto::md5::Md5;
+
+use rustc_serialize::base64::{self, FromBase64, ToBase64};
+use rustc_serialize::hex::ToHex;
+use std::fmt;
+use std::fmt::{Display, Formatter};
+
+use transport::smtp::NUL;
+use transport::smtp::error::Error;
+
+/// Represents authentication mechanisms
+#[derive(PartialEq,Eq,Copy,Clone,Hash,Debug)]
+pub enum Mechanism {
+    /// PLAIN authentication mechanism
+    /// RFC 4616: https://tools.ietf.org/html/rfc4616
+    Plain,
+    /// CRAM-MD5 authentication mechanism
+    /// RFC 2195: https://tools.ietf.org/html/rfc2195
+    CramMd5,
+}
+
+impl Display for Mechanism {
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        write!(f,
+               "{}",
+               match *self {
+                   Mechanism::Plain => "PLAIN",
+                   Mechanism::CramMd5 => "CRAM-MD5",
+               })
+    }
+}
+
+impl Mechanism {
+    /// Does the mechanism supports initial response
+    pub fn supports_initial_response(&self) -> bool {
+        match *self {
+            Mechanism::Plain => true,
+            Mechanism::CramMd5 => false,
+        }
+    }
+
+    /// Returns the string to send to the server, using the provided username, password and
+    /// challenge in some cases
+    pub fn response(&self,
+                    username: &str,
+                    password: &str,
+                    challenge: Option<&str>)
+                    -> Result<String, Error> {
+        match *self {
+            Mechanism::Plain => {
+                match challenge {
+                    Some(_) => Err(Error::Client("This mechanism does not expect a challenge")),
+                    None => {
+                        Ok(format!("{}{}{}{}", NUL, username, NUL, password)
+                            .as_bytes()
+                            .to_base64(base64::STANDARD))
+                    }
+                }
+            }
+            Mechanism::CramMd5 => {
+                let encoded_challenge = match challenge {
+                    Some(challenge) => challenge,
+                    None => return Err(Error::Client("This mechanism does expect a challenge")),
+                };
+
+                let decoded_challenge = match encoded_challenge.from_base64() {
+                    Ok(challenge) => challenge,
+                    Err(error) => return Err(Error::ChallengeParsing(error)),
+                };
+
+                let mut hmac = Hmac::new(Md5::new(), password.as_bytes());
+                hmac.input(&decoded_challenge);
+
+                Ok(format!("{} {}", username, hmac.result().code().to_hex())
+                    .as_bytes()
+                    .to_base64(base64::STANDARD))
+            }
+        }
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::Mechanism;
+
+    #[test]
+    fn test_plain() {
+        let mechanism = Mechanism::Plain;
+
+        assert_eq!(mechanism.response("username", "password", None).unwrap(),
+                   "AHVzZXJuYW1lAHBhc3N3b3Jk");
+        assert!(mechanism.response("username", "password", Some("test")).is_err());
+    }
+
+    #[test]
+    fn test_cram_md5() {
+        let mechanism = Mechanism::CramMd5;
+
+        assert_eq!(mechanism.response("alice",
+                                 "wonderland",
+                                 Some("PDE3ODkzLjEzMjA2NzkxMjNAdGVzc2VyYWN0LnN1c2FtLmluPg=="))
+                       .unwrap(),
+                   "YWxpY2UgNjRiMmE0M2MxZjZlZDY4MDZhOTgwOTE0ZTIzZTc1ZjA=");
+        assert!(mechanism.response("alice", "wonderland", Some("tést")).is_err());
+        assert!(mechanism.response("alice", "wonderland", None).is_err());
+    }
+}

src/transport/smtp/client/mod.rs

@@ -1,19 +1,19 @@
 //! SMTP client
 
-use std::string::String;
-use std::net::ToSocketAddrs;
-use std::io::{BufRead, Read, Write};
-use std::io;
-use std::fmt::Debug;
 
 use bufstream::BufStream;
 use openssl::ssl::SslContext;
+use std::fmt::Debug;
+use std::io;
+use std::io::{BufRead, Read, Write};
+use std::net::ToSocketAddrs;
+use std::string::String;
+use transport::smtp::{CRLF, MESSAGE_ENDING};
+use transport::smtp::authentication::Mechanism;
+use transport::smtp::client::net::{Connector, NetworkStream};
 
-use response::ResponseParser;
-use authentication::Mecanism;
-use error::{Error, SmtpResult};
-use client::net::{Connector, NetworkStream};
-use {CRLF, MESSAGE_ENDING};
+use transport::smtp::error::{SmtpResult, Error};
+use transport::smtp::response::ResponseParser;
 
 pub mod net;
 
@@ -22,11 +22,11 @@ pub mod net;
 /// Reference : https://tools.ietf.org/html/rfc5321#page-62 (4.5.2. Transparency)
 #[inline]
 fn escape_dot(string: &str) -> String {
-    if string.starts_with(".") {
-        format!(".{}", string)
-    } else {
-        string.to_string()
-    }
+    if string.starts_with('.') {
+            format!(".{}", string)
+        } else {
+            string.to_string()
+        }
         .replace("\r.", "\r..")
         .replace("\n.", "\n..")
 }
@@ -44,6 +44,7 @@ fn remove_crlf(string: &str) -> String {
 }
 
 /// Structure that implements the SMTP client
+#[derive(Debug)]
 pub struct Client<S: Write + Read = NetworkStream> {
     /// TCP stream between client and server
     /// Value is None before connection
@@ -56,7 +57,7 @@ macro_rules! return_err (
     })
 );
 
-impl<S: Write + Read = NetworkStream> Client<S> {
+impl<S: Write + Read> Client<S> {
     /// Creates a new SMTP client
     ///
     /// It does not connects to the server, but only creates the `Client`
@@ -65,7 +66,7 @@ impl<S: Write + Read = NetworkStream> Client<S> {
     }
 }
 
-impl<S: Connector + Write + Read + Debug + Clone = NetworkStream> Client<S> {
+impl<S: Connector + Write + Read + Debug> Client<S> {
     /// Closes the SMTP transaction if possible
     pub fn close(&mut self) {
         let _ = self.quit();
@@ -79,16 +80,25 @@ impl<S: Connector + Write + Read + Debug + Clone = NetworkStream> Client<S> {
 
     /// Upgrades the underlying connection to SSL/TLS
     pub fn upgrade_tls_stream(&mut self, ssl_context: &SslContext) -> io::Result<()> {
-        //let current_stream = self.stream.clone();
-        if self.stream.is_some() {
-            self.stream.as_mut().unwrap().get_mut().upgrade_tls(ssl_context)
-        } else {
-            Ok(())
+        match self.stream {
+            Some(ref mut stream) => stream.get_mut().upgrade_tls(ssl_context),
+            None => Ok(()),
+        }
+    }
+
+    /// Tells if the underlying stream is currently encrypted
+    pub fn is_encrypted(&self) -> bool {
+        match self.stream {
+            Some(ref stream) => stream.get_ref().is_encrypted(),
+            None => false,
         }
     }
 
     /// Connects to the configured server
-    pub fn connect<A: ToSocketAddrs>(&mut self, addr: &A) -> SmtpResult {
+    pub fn connect<A: ToSocketAddrs>(&mut self,
+                                     addr: &A,
+                                     ssl_context: Option<&SslContext>)
+                                     -> SmtpResult {
         // Connect should not be called when the client is already connected
         if self.stream.is_some() {
             return_err!("The connection is already established", self);
@@ -101,8 +111,10 @@ impl<S: Connector + Write + Read + Debug + Clone = NetworkStream> Client<S> {
             None => return_err!("Could not resolve hostname", self),
         };
 
+        debug!("connecting to {}", server_addr);
+
         // Try to connect
-        self.set_stream(try!(Connector::connect(&server_addr, None)));
+        self.set_stream(try!(Connector::connect(&server_addr, ssl_context)));
 
         self.get_reply()
     }
@@ -173,26 +185,26 @@ impl<S: Connector + Write + Read + Debug + Clone = NetworkStream> Client<S> {
         self.command("RSET")
     }
 
-    /// Sends an AUTH command with the given mecanism
-    pub fn auth(&mut self, mecanism: Mecanism, username: &str, password: &str) -> SmtpResult {
+    /// Sends an AUTH command with the given mechanism
+    pub fn auth(&mut self, mechanism: Mechanism, username: &str, password: &str) -> SmtpResult {
 
-        if mecanism.supports_initial_response() {
+        if mechanism.supports_initial_response() {
             self.command(&format!("AUTH {} {}",
-                                  mecanism,
-                                  try!(mecanism.response(username, password, None))))
+                                  mechanism,
+                                  try!(mechanism.response(username, password, None))))
         } else {
             let encoded_challenge = match try!(self.command("AUTH CRAM-MD5")).first_word() {
                 Some(challenge) => challenge,
-                None => return Err(Error::ResponseParsingError("Could not read CRAM challenge")),
+                None => return Err(Error::ResponseParsing("Could not read CRAM challenge")),
             };
 
             debug!("CRAM challenge: {}", encoded_challenge);
 
-            let cram_response = try!(mecanism.response(username,
-                                                       password,
-                                                       Some(&encoded_challenge)));
+            let cram_response = try!(mechanism.response(username,
+                                                        password,
+                                                        Some(&encoded_challenge)));
 
-            self.command(&format!("{}", cram_response))
+            self.command(&cram_response.clone())
         }
     }
 
@@ -223,7 +235,7 @@ impl<S: Connector + Write + Read + Debug + Clone = NetworkStream> Client<S> {
     /// Gets the SMTP response
     fn get_reply(&mut self) -> SmtpResult {
 
-        let mut parser = ResponseParser::new();
+        let mut parser = ResponseParser::default();
 
         let mut line = String::new();
         try!(self.stream.as_mut().unwrap().read_line(&mut line));
@@ -237,16 +249,18 @@ impl<S: Connector + Write + Read + Debug + Clone = NetworkStream> Client<S> {
 
         let response = try!(parser.response());
 
-        match response.is_positive() {
-            true => Ok(response),
-            false => Err(From::from(response)),
+        if response.is_positive() {
+            Ok(response)
+        } else {
+            Err(From::from(response))
         }
+
     }
 }
 
 #[cfg(test)]
 mod test {
-    use super::{escape_dot, remove_crlf, escape_crlf};
+    use super::{escape_crlf, escape_dot, remove_crlf};
 
     #[test]
     fn test_escape_dot() {

src/transport/smtp/client/net.rs

@@ -1,19 +1,20 @@
 //! A trait to represent a stream
 
-use std::io;
-use std::io::{Read, Write, ErrorKind};
-use std::net::SocketAddr;
-use std::net::TcpStream;
+use openssl::ssl::{Ssl, SslContext, SslStream};
 use std::fmt;
 use std::fmt::{Debug, Formatter};
-use openssl::ssl::{SslContext, SslStream};
+use std::io;
+use std::io::{ErrorKind, Read, Write};
+use std::net::{SocketAddr, TcpStream};
 
 /// A trait for the concept of opening a stream
-pub trait Connector {
+pub trait Connector: Sized {
     /// Opens a connection to the given IP socket
     fn connect(addr: &SocketAddr, ssl_context: Option<&SslContext>) -> io::Result<Self>;
     /// Upgrades to TLS connection
     fn upgrade_tls(&mut self, ssl_context: &SslContext) -> io::Result<()>;
+    /// Is the NetworkStream encrypted
+    fn is_encrypted(&self) -> bool;
 }
 
 impl Connector for NetworkStream {
@@ -21,23 +22,46 @@ impl Connector for NetworkStream {
         let tcp_stream = try!(TcpStream::connect(addr));
 
         match ssl_context {
-            Some(context) => match SslStream::new(&context, tcp_stream) {
-                Ok(stream) => Ok(NetworkStream::Ssl(stream)),
-                Err(err) => Err(io::Error::new(ErrorKind::Other, err)),
-            },
+            Some(context) => {
+                match Ssl::new(context) {
+                    Ok(ssl) => {
+                        ssl.connect(tcp_stream)
+                            .map(|s| NetworkStream::Ssl(s))
+                            .map_err(|e| io::Error::new(ErrorKind::Other, e))
+                    }
+                    Err(e) => Err(io::Error::new(ErrorKind::Other, e)),
+                }
+            }
             None => Ok(NetworkStream::Plain(tcp_stream)),
         }
     }
 
     fn upgrade_tls(&mut self, ssl_context: &SslContext) -> io::Result<()> {
-        *self = match self.clone() {
-            NetworkStream::Plain(stream) => match SslStream::new(ssl_context, stream) {
-                Ok(ssl_stream) => NetworkStream::Ssl(ssl_stream),
-                Err(err) => return Err(io::Error::new(ErrorKind::Other, err)),
-            },
-            NetworkStream::Ssl(stream) => NetworkStream::Ssl(stream),
+
+        *self = match *self {
+            NetworkStream::Plain(ref mut stream) => {
+                match Ssl::new(ssl_context) {
+                    Ok(ssl) => {
+                        match ssl.connect(stream.try_clone().unwrap()) {
+                            Ok(ssl_stream) => NetworkStream::Ssl(ssl_stream),
+                            Err(err) => return Err(io::Error::new(ErrorKind::Other, err)),
+                        }
+                    }
+                    Err(e) => return Err(io::Error::new(ErrorKind::Other, e)),
+                }
+            }
+            NetworkStream::Ssl(_) => return Ok(()),
         };
+
         Ok(())
+
+    }
+
+    fn is_encrypted(&self) -> bool {
+        match *self {
+            NetworkStream::Plain(_) => false,
+            NetworkStream::Ssl(_) => true,
+        }
     }
 }
 
@@ -50,16 +74,6 @@ pub enum NetworkStream {
     Ssl(SslStream<TcpStream>),
 }
 
-impl Clone for NetworkStream {
-    #[inline]
-    fn clone(&self) -> NetworkStream {
-        match self {
-            &NetworkStream::Plain(ref stream) => NetworkStream::Plain(stream.try_clone().unwrap()),
-            &NetworkStream::Ssl(ref stream) => NetworkStream::Ssl(stream.try_clone().unwrap()),
-        }
-    }
-}
-
 impl Debug for NetworkStream {
     fn fmt(&self, f: &mut Formatter) -> fmt::Result {
         f.write_str("NetworkStream(_)")

src/transport/smtp/error.rs

@@ -1,13 +1,13 @@
 //! Error and result type for SMTP clients
 
-use std::error::Error as StdError;
-use std::io;
-use std::fmt::{Display, Formatter};
-use std::fmt;
-
-use response::{Severity, Response};
-use serialize::base64::FromBase64Error;
+use rustc_serialize::base64::FromBase64Error;
 use self::Error::*;
+use std::error::Error as StdError;
+use std::fmt;
+use std::fmt::{Display, Formatter};
+use std::io;
+
+use transport::smtp::response::{Response, Severity};
 
 /// An enum of all error kinds.
 #[derive(Debug)]
@@ -15,21 +15,21 @@ pub enum Error {
     /// Transient SMTP error, 4xx reply code
     ///
     /// [RFC 5321, section 4.2.1](https://tools.ietf.org/html/rfc5321#section-4.2.1)
-    TransientError(Response),
+    Transient(Response),
     /// Permanent SMTP error, 5xx reply code
     ///
     /// [RFC 5321, section 4.2.1](https://tools.ietf.org/html/rfc5321#section-4.2.1)
-    PermanentError(Response),
+    Permanent(Response),
     /// Error parsing a response
-    ResponseParsingError(&'static str),
+    ResponseParsing(&'static str),
     /// Error parsing a base64 string in response
-    ChallengeParsingError(FromBase64Error),
+    ChallengeParsing(FromBase64Error),
     /// Internal client error
-    ClientError(&'static str),
+    Client(&'static str),
     /// DNS resolution error
-    ResolutionError,
+    Resolution,
     /// IO error
-    IoError(io::Error),
+    Io(io::Error),
 }
 
 impl Display for Error {
@@ -41,19 +41,19 @@ impl Display for Error {
 impl StdError for Error {
     fn description(&self) -> &str {
         match *self {
-            TransientError(_) => "a transient error occured during the SMTP transaction",
-            PermanentError(_) => "a permanent error occured during the SMTP transaction",
-            ResponseParsingError(_) => "an error occured while parsing an SMTP response",
-            ChallengeParsingError(_) => "an error occured while parsing a CRAM-MD5 challenge",
-            ResolutionError => "Could no resolve hostname",
-            ClientError(_) => "an unknown error occured",
-            IoError(_) => "an I/O error occured",
+            Transient(_) => "a transient error occured during the SMTP transaction",
+            Permanent(_) => "a permanent error occured during the SMTP transaction",
+            ResponseParsing(_) => "an error occured while parsing an SMTP response",
+            ChallengeParsing(_) => "an error occured while parsing a CRAM-MD5 challenge",
+            Resolution => "could not resolve hostname",
+            Client(_) => "an unknown error occured",
+            Io(_) => "an I/O error occured",
         }
     }
 
     fn cause(&self) -> Option<&StdError> {
         match *self {
-            IoError(ref err) => Some(&*err as &StdError),
+            Io(ref err) => Some(&*err as &StdError),
             _ => None,
         }
     }
@@ -61,30 +61,25 @@ impl StdError for Error {
 
 impl From<io::Error> for Error {
     fn from(err: io::Error) -> Error {
-        IoError(err)
+        Io(err)
     }
 }
 
 impl From<Response> for Error {
     fn from(response: Response) -> Error {
         match response.severity() {
-            Severity::TransientNegativeCompletion => TransientError(response),
-            Severity::PermanentNegativeCompletion => PermanentError(response),
-            _ => ClientError("Unknown error code"),
+            Severity::TransientNegativeCompletion => Transient(response),
+            Severity::PermanentNegativeCompletion => Permanent(response),
+            _ => Client("Unknown error code"),
         }
     }
 }
 
 impl From<&'static str> for Error {
     fn from(string: &'static str) -> Error {
-        ClientError(string)
+        Client(string)
     }
 }
 
 /// SMTP result type
 pub type SmtpResult = Result<Response, Error>;
-
-#[cfg(test)]
-mod test {
-    // TODO
-}

src/transport/smtp/extension.rs

@@ -1,13 +1,13 @@
 //! ESMTP features
 
-use std::result::Result;
-use std::fmt::{Display, Formatter};
-use std::fmt;
 use std::collections::HashSet;
+use std::fmt;
+use std::fmt::{Display, Formatter};
+use std::result::Result;
+use transport::smtp::authentication::Mechanism;
 
-use response::Response;
-use error::Error;
-use authentication::Mecanism;
+use transport::smtp::error::Error;
+use transport::smtp::response::Response;
 
 /// Supported ESMTP keywords
 #[derive(PartialEq,Eq,Hash,Clone,Debug)]
@@ -24,8 +24,8 @@ pub enum Extension {
     ///
     /// RFC 2487: https://tools.ietf.org/html/rfc2487
     StartTls,
-    /// AUTH mecanism
-    Authentication(Mecanism),
+    /// AUTH mechanism
+    Authentication(Mechanism),
 }
 
 impl Display for Extension {
@@ -34,7 +34,7 @@ impl Display for Extension {
             Extension::EightBitMime => write!(f, "{}", "8BITMIME"),
             Extension::SmtpUtfEight => write!(f, "{}", "SMTPUTF8"),
             Extension::StartTls => write!(f, "{}", "STARTTLS"),
-            Extension::Authentication(ref mecanism) => write!(f, "{} {}", "AUTH", mecanism),
+            Extension::Authentication(ref mechanism) => write!(f, "{} {}", "AUTH", mechanism),
         }
     }
 }
@@ -69,7 +69,7 @@ impl ServerInfo {
     pub fn from_response(response: &Response) -> Result<ServerInfo, Error> {
         let name = match response.first_word() {
             Some(name) => name,
-            None => return Err(Error::ResponseParsingError("Could not read server name")),
+            None => return Err(Error::ResponseParsing("Could not read server name")),
         };
 
         let mut features: HashSet<Extension> = HashSet::new();
@@ -77,7 +77,7 @@ impl ServerInfo {
         for line in response.message() {
 
             let splitted: Vec<&str> = line.split_whitespace().collect();
-            let _ = match splitted[0] {
+            match splitted[0] {
                 "8BITMIME" => {
                     features.insert(Extension::EightBitMime);
                 }
@@ -88,13 +88,13 @@ impl ServerInfo {
                     features.insert(Extension::StartTls);
                 }
                 "AUTH" => {
-                    for &mecanism in &splitted[1..] {
-                        match mecanism {
+                    for &mechanism in &splitted[1..] {
+                        match mechanism {
                             "PLAIN" => {
-                                features.insert(Extension::Authentication(Mecanism::Plain));
+                                features.insert(Extension::Authentication(Mechanism::Plain));
                             }
                             "CRAM-MD5" => {
-                                features.insert(Extension::Authentication(Mecanism::CramMd5));
+                                features.insert(Extension::Authentication(Mechanism::CramMd5));
                             }
                             _ => (),
                         }
@@ -116,8 +116,8 @@ impl ServerInfo {
     }
 
     /// Checks if the server supports an ESMTP feature
-    pub fn supports_auth_mecanism(&self, mecanism: Mecanism) -> bool {
-        self.features.contains(&Extension::Authentication(mecanism))
+    pub fn supports_auth_mechanism(&self, mechanism: Mechanism) -> bool {
+        self.features.contains(&Extension::Authentication(mechanism))
     }
 }
 
@@ -125,15 +125,15 @@ impl ServerInfo {
 mod test {
     use std::collections::HashSet;
 
-    use super::{ServerInfo, Extension};
-    use authentication::Mecanism;
-    use response::{Code, Response, Severity, Category};
+    use super::{Extension, ServerInfo};
+    use transport::smtp::authentication::Mechanism;
+    use transport::smtp::response::{Category, Code, Response, Severity};
 
     #[test]
     fn test_extension_fmt() {
         assert_eq!(format!("{}", Extension::EightBitMime),
                    "8BITMIME".to_string());
-        assert_eq!(format!("{}", Extension::Authentication(Mecanism::Plain)),
+        assert_eq!(format!("{}", Extension::Authentication(Mechanism::Plain)),
                    "AUTH PLAIN".to_string());
     }
 
@@ -159,7 +159,7 @@ mod test {
                    "name with no supported features".to_string());
 
         let mut plain = HashSet::new();
-        assert!(plain.insert(Extension::Authentication(Mecanism::Plain)));
+        assert!(plain.insert(Extension::Authentication(Mechanism::Plain)));
 
         assert_eq!(format!("{}",
                            ServerInfo {
@@ -171,12 +171,9 @@ mod test {
 
     #[test]
     fn test_serverinfo() {
-        let response = Response::new(Code::new(Severity::PositiveCompletion,
-                                               Category::Unspecified4,
-                                               1),
-                                     vec!["me".to_string(),
-                                          "8BITMIME".to_string(),
-                                          "SIZE 42".to_string()]);
+        let response =
+            Response::new(Code::new(Severity::PositiveCompletion, Category::Unspecified4, 1),
+                          vec!["me".to_string(), "8BITMIME".to_string(), "SIZE 42".to_string()]);
 
         let mut features = HashSet::new();
         assert!(features.insert(Extension::EightBitMime));
@@ -190,20 +187,19 @@ mod test {
 
         assert!(server_info.supports_feature(&Extension::EightBitMime));
         assert!(!server_info.supports_feature(&Extension::StartTls));
-        assert!(!server_info.supports_auth_mecanism(Mecanism::CramMd5));
+        assert!(!server_info.supports_auth_mechanism(Mechanism::CramMd5));
 
-        let response2 = Response::new(Code::new(Severity::PositiveCompletion,
-                                                Category::Unspecified4,
-                                                1),
-                                      vec!["me".to_string(),
-                                           "AUTH PLAIN CRAM-MD5 OTHER".to_string(),
-                                           "8BITMIME".to_string(),
-                                           "SIZE 42".to_string()]);
+        let response2 =
+            Response::new(Code::new(Severity::PositiveCompletion, Category::Unspecified4, 1),
+                          vec!["me".to_string(),
+                               "AUTH PLAIN CRAM-MD5 OTHER".to_string(),
+                               "8BITMIME".to_string(),
+                               "SIZE 42".to_string()]);
 
         let mut features2 = HashSet::new();
         assert!(features2.insert(Extension::EightBitMime));
-        assert!(features2.insert(Extension::Authentication(Mecanism::Plain)));
-        assert!(features2.insert(Extension::Authentication(Mecanism::CramMd5)));
+        assert!(features2.insert(Extension::Authentication(Mechanism::Plain)));
+        assert!(features2.insert(Extension::Authentication(Mechanism::CramMd5)));
 
         let server_info2 = ServerInfo {
             name: "me".to_string(),
@@ -213,8 +209,8 @@ mod test {
         assert_eq!(ServerInfo::from_response(&response2).unwrap(), server_info2);
 
         assert!(server_info2.supports_feature(&Extension::EightBitMime));
-        assert!(server_info2.supports_auth_mecanism(Mecanism::Plain));
-        assert!(server_info2.supports_auth_mecanism(Mecanism::CramMd5));
+        assert!(server_info2.supports_auth_mechanism(Mechanism::Plain));
+        assert!(server_info2.supports_auth_mechanism(Mechanism::CramMd5));
         assert!(!server_info2.supports_feature(&Extension::StartTls));
     }
 }

src/transport/smtp/mod.rs

@@ -0,0 +1,419 @@
+//! This transport sends emails using the SMTP protocol
+
+use email::SendableEmail;
+
+use openssl::ssl::{SslContext, SslMethod};
+use std::net::{SocketAddr, ToSocketAddrs};
+use std::string::String;
+use transport::EmailTransport;
+use transport::smtp::authentication::Mechanism;
+use transport::smtp::client::Client;
+
+use transport::smtp::error::{SmtpResult, Error};
+use transport::smtp::extension::{Extension, ServerInfo};
+
+pub mod extension;
+pub mod authentication;
+pub mod response;
+pub mod client;
+pub mod error;
+
+// Registrated port numbers:
+// https://www.iana.
+// org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml
+
+/// Default smtp port
+pub const SMTP_PORT: u16 = 25;
+
+/// Default submission port
+pub const SUBMISSION_PORT: u16 = 587;
+
+// Useful strings and characters
+
+/// The word separator for SMTP transactions
+pub const SP: &'static str = " ";
+
+/// The line ending for SMTP transactions (carriage return + line feed)
+pub const CRLF: &'static str = "\r\n";
+
+/// Colon
+pub const COLON: &'static str = ":";
+
+/// The ending of message content
+pub const MESSAGE_ENDING: &'static str = "\r\n.\r\n";
+
+/// NUL unicode character
+pub const NUL: &'static str = "\0";
+
+/// TLS security level
+#[derive(Debug)]
+pub enum SecurityLevel {
+    /// Use a TLS wrapped connection
+    ///
+    /// Non RFC-compliant, should only be used if the server does not support STARTTLS.
+    EncryptedWrapper,
+    /// Only send an email on encrypted connection (with STARTTLS)
+    ///
+    /// Recommended mode, prevents MITM when used with verified certificates.
+    AlwaysEncrypt,
+    /// Use TLS when available (with STARTTLS)
+    ///
+    /// Default mode.
+    Opportunistic,
+    /// Never use TLS
+    NeverEncrypt,
+}
+
+/// Contains client configuration
+pub struct SmtpTransportBuilder {
+    /// Maximum connection reuse
+    ///
+    /// Zero means no limitation
+    connection_reuse_count_limit: u16,
+    /// Enable connection reuse
+    connection_reuse: bool,
+    /// Name sent during HELO or EHLO
+    hello_name: String,
+    /// Credentials
+    credentials: Option<(String, String)>,
+    /// Socket we are connecting to
+    server_addr: SocketAddr,
+    /// SSL context to use
+    ssl_context: SslContext,
+    /// TLS security level
+    security_level: SecurityLevel,
+    /// Enable UTF8 mailboxes in envelope or headers
+    smtp_utf8: bool,
+    /// Optional enforced authentication mechanism
+    authentication_mechanism: Option<Mechanism>,
+}
+
+/// Builder for the SMTP `SmtpTransport`
+impl SmtpTransportBuilder {
+    /// Creates a new local SMTP client
+    pub fn new<A: ToSocketAddrs>(addr: A) -> Result<SmtpTransportBuilder, Error> {
+        let mut addresses = try!(addr.to_socket_addrs());
+
+        match addresses.next() {
+            Some(addr) => {
+                Ok(SmtpTransportBuilder {
+                    server_addr: addr,
+                    ssl_context: SslContext::builder(SslMethod::tls()).unwrap().build(),
+                    security_level: SecurityLevel::Opportunistic,
+                    smtp_utf8: false,
+                    credentials: None,
+                    connection_reuse_count_limit: 100,
+                    connection_reuse: false,
+                    hello_name: "localhost".to_string(),
+                    authentication_mechanism: None,
+                })
+            }
+            None => Err(From::from("Could nor resolve hostname")),
+        }
+    }
+
+    /// Creates a new local SMTP client to port 25
+    pub fn localhost() -> Result<SmtpTransportBuilder, Error> {
+        SmtpTransportBuilder::new(("localhost", SMTP_PORT))
+    }
+
+    /// Use STARTTLS with a specific context
+    pub fn ssl_context(mut self, ssl_context: SslContext) -> SmtpTransportBuilder {
+        self.ssl_context = ssl_context;
+        self
+    }
+
+    /// Set the security level for SSL/TLS
+    pub fn security_level(mut self, level: SecurityLevel) -> SmtpTransportBuilder {
+        self.security_level = level;
+        self
+    }
+
+    /// Require SSL/TLS using STARTTLS
+    ///
+    /// Incompatible with `ssl_wrapper()``
+    pub fn encrypt(mut self) -> SmtpTransportBuilder {
+        self.security_level = SecurityLevel::AlwaysEncrypt;
+        self
+    }
+
+    /// Require SSL/TLS using SMTPS
+    ///
+    /// Incompatible with `encrypt()`
+    pub fn ssl_wrapper(mut self) -> SmtpTransportBuilder {
+        self.security_level = SecurityLevel::EncryptedWrapper;
+        self
+    }
+
+    /// Enable SMTPUTF8 if the server supports it
+    pub fn smtp_utf8(mut self, enabled: bool) -> SmtpTransportBuilder {
+        self.smtp_utf8 = enabled;
+        self
+    }
+
+    /// Set the name used during HELO or EHLO
+    pub fn hello_name(mut self, name: &str) -> SmtpTransportBuilder {
+        self.hello_name = name.to_string();
+        self
+    }
+
+    /// Enable connection reuse
+    pub fn connection_reuse(mut self, enable: bool) -> SmtpTransportBuilder {
+        self.connection_reuse = enable;
+        self
+    }
+
+    /// Set the maximum number of emails sent using one connection
+    pub fn connection_reuse_count_limit(mut self, limit: u16) -> SmtpTransportBuilder {
+        self.connection_reuse_count_limit = limit;
+        self
+    }
+
+    /// Set the client credentials
+    pub fn credentials(mut self, username: &str, password: &str) -> SmtpTransportBuilder {
+        self.credentials = Some((username.to_string(), password.to_string()));
+        self
+    }
+
+    /// Set the authentication mechanisms
+    pub fn authentication_mechanism(mut self, mechanism: Mechanism) -> SmtpTransportBuilder {
+        self.authentication_mechanism = Some(mechanism);
+        self
+    }
+
+    /// Build the SMTP client
+    ///
+    /// It does not connect to the server, but only creates the `SmtpTransport`
+    pub fn build(self) -> SmtpTransport {
+        SmtpTransport::new(self)
+    }
+}
+
+/// Represents the state of a client
+#[derive(Debug)]
+struct State {
+    /// Panic state
+    pub panic: bool,
+    /// Connection reuse counter
+    pub connection_reuse_count: u16,
+}
+
+/// Structure that implements the high level SMTP client
+pub struct SmtpTransport {
+    /// Information about the server
+    /// Value is None before HELO/EHLO
+    server_info: Option<ServerInfo>,
+    /// SmtpTransport variable states
+    state: State,
+    /// Information about the client
+    client_info: SmtpTransportBuilder,
+    /// Low level client
+    client: Client,
+}
+
+macro_rules! try_smtp (
+    ($err: expr, $client: ident) => ({
+        match $err {
+            Ok(val) => val,
+            Err(err) => {
+                if !$client.state.panic {
+                    $client.state.panic = true;
+                    $client.reset();
+                }
+                return Err(From::from(err))
+            },
+        }
+    })
+);
+
+impl SmtpTransport {
+    /// Creates a new SMTP client
+    ///
+    /// It does not connect to the server, but only creates the `SmtpTransport`
+    pub fn new(builder: SmtpTransportBuilder) -> SmtpTransport {
+
+        let client = Client::new();
+
+        SmtpTransport {
+            client: client,
+            server_info: None,
+            client_info: builder,
+            state: State {
+                panic: false,
+                connection_reuse_count: 0,
+            },
+        }
+    }
+
+    /// Reset the client state
+    fn reset(&mut self) {
+        // Close the SMTP transaction if needed
+        self.close();
+
+        // Reset the client state
+        self.server_info = None;
+        self.state.panic = false;
+        self.state.connection_reuse_count = 0;
+    }
+
+    /// Gets the EHLO response and updates server information
+    pub fn get_ehlo(&mut self) -> SmtpResult {
+        // Extended Hello
+        let ehlo_response = try_smtp!(self.client.ehlo(&self.client_info.hello_name), self);
+
+        self.server_info = Some(try_smtp!(ServerInfo::from_response(&ehlo_response), self));
+
+        // Print server information
+        debug!("server {}", self.server_info.as_ref().unwrap());
+
+        Ok(ehlo_response)
+    }
+}
+
+impl EmailTransport<SmtpResult> for SmtpTransport {
+    /// Sends an email
+    fn send<T: SendableEmail>(&mut self, email: T) -> SmtpResult {
+
+        // Extract email information
+        let message_id = email.message_id();
+        let from_address = email.from_address();
+        let to_addresses = email.to_addresses();
+        let message = email.message();
+
+        // Check if the connection is still available
+        if (self.state.connection_reuse_count > 0) && (!self.client.is_connected()) {
+            self.reset();
+        }
+
+        if self.state.connection_reuse_count == 0 {
+            try!(self.client.connect(&self.client_info.server_addr,
+                                     match &self.client_info.security_level {
+                                         &SecurityLevel::EncryptedWrapper => {
+                                             Some(&self.client_info.ssl_context)
+                                         }
+                                         _ => None,
+                                     }));
+
+            // Log the connection
+            info!("connection established to {}", self.client_info.server_addr);
+
+            try!(self.get_ehlo());
+
+            match (&self.client_info.security_level,
+                   self.server_info.as_ref().unwrap().supports_feature(&Extension::StartTls)) {
+                (&SecurityLevel::AlwaysEncrypt, false) => {
+                    return Err(From::from("Could not encrypt connection, aborting"))
+                }
+                (&SecurityLevel::Opportunistic, false) => (),
+                (&SecurityLevel::NeverEncrypt, _) => (),
+                (&SecurityLevel::EncryptedWrapper, _) => (),
+                (_, true) => {
+                    try_smtp!(self.client.starttls(), self);
+                    try_smtp!(self.client.upgrade_tls_stream(&self.client_info.ssl_context),
+                              self);
+
+                    debug!("connection encrypted");
+
+                    // Send EHLO again
+                    try!(self.get_ehlo());
+                }
+            }
+
+            if self.client_info.credentials.is_some() {
+                let (username, password) = self.client_info.credentials.clone().unwrap();
+
+                let mut found = false;
+
+                // Compute accepted mechanism
+                let accepted_mechanisms = match self.client_info.authentication_mechanism {
+                    Some(mechanism) => vec![mechanism],
+                    None => {
+                        if self.client.is_encrypted() {
+                            // If encrypted, allow all mechanisms, with a preference for the
+                            // simplest
+                            vec![Mechanism::Plain, Mechanism::CramMd5]
+                        } else {
+                            // If not encrypted, do not allow clear-text passwords
+                            vec![Mechanism::CramMd5]
+                        }
+                    }
+                };
+
+                for mechanism in accepted_mechanisms {
+                    if self.server_info.as_ref().unwrap().supports_auth_mechanism(mechanism) {
+                        found = true;
+                        try_smtp!(self.client.auth(mechanism, &username, &password), self);
+                        break;
+                    }
+                }
+
+                if !found {
+                    info!("No supported authentication mechanisms available");
+                }
+            }
+        }
+
+        // Mail
+        let mail_options = match (self.server_info
+            .as_ref()
+            .unwrap()
+            .supports_feature(&Extension::EightBitMime),
+                                  self.server_info
+            .as_ref()
+            .unwrap()
+            .supports_feature(&Extension::SmtpUtfEight)) {
+            (true, true) => Some("BODY=8BITMIME SMTPUTF8"),
+            (true, false) => Some("BODY=8BITMIME"),
+            (false, _) => None,
+        };
+
+        try_smtp!(self.client.mail(&from_address, mail_options), self);
+
+        // Log the mail command
+        info!("{}: from=<{}>", message_id, from_address);
+
+        // Recipient
+        for to_address in &to_addresses {
+            try_smtp!(self.client.rcpt(&to_address), self);
+            // Log the rcpt command
+            info!("{}: to=<{}>", message_id, to_address);
+        }
+
+        // Data
+        try_smtp!(self.client.data(), self);
+
+        // Message content
+        let result = self.client.message(&message);
+
+        if result.is_ok() {
+            // Increment the connection reuse counter
+            self.state.connection_reuse_count += 1;
+
+            // Log the message
+            info!("{}: conn_use={}, size={}, status=sent ({})",
+                  message_id,
+                  self.state.connection_reuse_count,
+                  message.len(),
+                  result.as_ref()
+                        .ok()
+                        .unwrap()
+                        .message()
+                        .iter()
+                        .next()
+                        .unwrap_or(&"no response".to_string()));
+        }
+
+        // Test if we can reuse the existing connection
+        if (!self.client_info.connection_reuse) ||
+           (self.state.connection_reuse_count >= self.client_info.connection_reuse_count_limit) {
+            self.reset();
+        }
+
+        result
+    }
+
+    /// Closes the inner connection
+    fn close(&mut self) {
+        self.client.close();
+    }
+}

src/transport/smtp/response.rs

@@ -1,12 +1,14 @@
-//! SMTP response, containing a mandatory return code and an optional text message
+//! SMTP response, containing a mandatory return code and an optional text
+//! message
 
-use std::str::FromStr;
-use std::fmt::{Display, Formatter, Result};
-use std::result;
+use self::Category::*;
 
 use self::Severity::*;
-use self::Category::*;
-use error::{SmtpResult, Error};
+use std::fmt::{Display, Formatter, Result};
+use std::result;
+use std::str::FromStr;
+use transport::smtp::error::{Error, SmtpResult};
+
 
 /// First digit indicates severity
 #[derive(PartialEq,Eq,Copy,Clone,Debug)]
@@ -29,7 +31,7 @@ impl FromStr for Severity {
             "3" => Ok(PositiveIntermediate),
             "4" => Ok(TransientNegativeCompletion),
             "5" => Ok(PermanentNegativeCompletion),
-            _ => Err(Error::ResponseParsingError("First digit must be between 2 and 5")),
+            _ => Err(Error::ResponseParsing("First digit must be between 2 and 5")),
         }
     }
 }
@@ -74,7 +76,7 @@ impl FromStr for Category {
             "3" => Ok(Unspecified3),
             "4" => Ok(Unspecified4),
             "5" => Ok(MailSystem),
-            _ => Err(Error::ResponseParsingError("Second digit must be between 0 and 5")),
+            _ => Err(Error::ResponseParsing("Second digit must be between 0 and 5")),
         }
     }
 }
@@ -114,15 +116,17 @@ impl FromStr for Code {
             match (s[0..1].parse::<Severity>(),
                    s[1..2].parse::<Category>(),
                    s[2..3].parse::<u8>()) {
-                (Ok(severity), Ok(category), Ok(detail)) => Ok(Code {
-                    severity: severity,
-                    category: category,
-                    detail: detail,
-                }),
-                _ => return Err(Error::ResponseParsingError("Could not parse response code")),
+                (Ok(severity), Ok(category), Ok(detail)) => {
+                    Ok(Code {
+                        severity: severity,
+                        category: category,
+                        detail: detail,
+                    })
+                }
+                _ => Err(Error::ResponseParsing("Could not parse response code")),
             }
         } else {
-            Err(Error::ResponseParsingError("Wrong code length (should be 3 digit)"))
+            Err(Error::ResponseParsing("Wrong code length (should be 3 digit)"))
         }
     }
 }
@@ -144,7 +148,7 @@ impl Code {
 }
 
 /// Parses an SMTP response
-#[derive(PartialEq,Eq,Clone,Debug)]
+#[derive(PartialEq,Eq,Clone,Debug,Default)]
 pub struct ResponseParser {
     /// Response code
     code: Option<Code>,
@@ -154,25 +158,17 @@ pub struct ResponseParser {
 }
 
 impl ResponseParser {
-    /// Creates a new parser
-    pub fn new() -> ResponseParser {
-        ResponseParser {
-            code: None,
-            message: vec![],
-        }
-    }
-
     /// Parses a line and return a `bool` indicating if there are more lines to come
     pub fn read_line(&mut self, line: &str) -> result::Result<bool, Error> {
 
         if line.len() < 3 {
-            return Err(Error::ResponseParsingError("Wrong code length (should be 3 digit)"));
+            return Err(Error::ResponseParsing("Wrong code length (should be 3 digit)"));
         }
 
         match self.code {
             Some(ref code) => {
                 if code.code() != line[0..3] {
-                    return Err(Error::ResponseParsingError("Response code has changed during a \
+                    return Err(Error::ResponseParsing("Response code has changed during a \
                                                             reponse"));
                 }
             }
@@ -181,11 +177,7 @@ impl ResponseParser {
 
         if line.len() > 4 {
             self.message.push(line[4..].to_string());
-            if line.as_bytes()[3] == '-' as u8 {
-                Ok(true)
-            } else {
-                Ok(false)
-            }
+            Ok(line.as_bytes()[3] == b'-')
         } else {
             Ok(false)
         }
@@ -195,13 +187,15 @@ impl ResponseParser {
     pub fn response(self) -> SmtpResult {
         match self.code {
             Some(code) => Ok(Response::new(code, self.message)),
-            None => Err(Error::ResponseParsingError("Incomplete response, could not read \
-                                                     response code")),
+            None => {
+                Err(Error::ResponseParsing("Incomplete response, could not read response \
+                                                 code"))
+            }
         }
     }
 }
 
-/// Contains an SMTP reply, with separed code and message
+/// Contains an SMTP reply, with separated code and message
 ///
 /// The text message is optional, only the code is mandatory
 #[derive(PartialEq,Eq,Clone,Debug)]
@@ -263,19 +257,21 @@ impl Response {
 
     /// Returns only the first word of the message if possible
     pub fn first_word(&self) -> Option<String> {
-        match self.message.is_empty() {
-            true => None,
-            false => match self.message[0].split_whitespace().next() {
+        if self.message.is_empty() {
+            None
+        } else {
+            match self.message[0].split_whitespace().next() {
                 Some(word) => Some(word.to_string()),
                 None => None,
-            },
+            }
         }
+
     }
 }
 
 #[cfg(test)]
 mod test {
-    use super::{Severity, Category, Response, ResponseParser, Code};
+    use super::{Category, Code, Response, ResponseParser, Severity};
 
     #[test]
     fn test_severity_from_str() {
@@ -374,7 +370,7 @@ mod test {
 
     #[test]
     fn test_response_parser() {
-        let mut parser = ResponseParser::new();
+        let mut parser = ResponseParser::default();
 
         assert!(parser.read_line("250-me").unwrap());
         assert!(parser.read_line("250-8BITMIME").unwrap());
@@ -407,7 +403,7 @@ mod test {
                               vec!["me".to_string(),
                                    "8BITMIME".to_string(),
                                    "SIZE 42".to_string()])
-                    .is_positive());
+            .is_positive());
         assert!(!Response::new(Code {
                                    severity: "5".parse::<Severity>().unwrap(),
                                    category: "4".parse::<Category>().unwrap(),
@@ -416,7 +412,7 @@ mod test {
                                vec!["me".to_string(),
                                     "8BITMIME".to_string(),
                                     "SIZE 42".to_string()])
-                     .is_positive());
+            .is_positive());
     }
 
     #[test]
@@ -518,7 +514,7 @@ mod test {
                               vec!["me".to_string(),
                                    "8BITMIME".to_string(),
                                    "SIZE 42".to_string()])
-                    .has_code(241));
+            .has_code(241));
         assert!(!Response::new(Code {
                                    severity: "2".parse::<Severity>().unwrap(),
                                    category: "4".parse::<Category>().unwrap(),
@@ -527,7 +523,7 @@ mod test {
                                vec!["me".to_string(),
                                     "8BITMIME".to_string(),
                                     "SIZE 42".to_string()])
-                     .has_code(251));
+            .has_code(251));
     }
 
     #[test]

src/transport/stub/error.rs

@@ -0,0 +1,37 @@
+//! Error and result type for file transport
+
+use self::Error::*;
+use std::error::Error as StdError;
+use std::fmt;
+use std::fmt::{Display, Formatter};
+
+/// An enum of all error kinds.
+#[derive(Debug)]
+pub enum Error {
+    /// Internal client error
+    Client(&'static str),
+}
+
+impl Display for Error {
+    fn fmt(&self, fmt: &mut Formatter) -> Result<(), fmt::Error> {
+        fmt.write_str(self.description())
+    }
+}
+
+impl StdError for Error {
+    fn description(&self) -> &str {
+        match *self {
+            Client(_) => "an unknown error occured",
+        }
+    }
+
+    fn cause(&self) -> Option<&StdError> {
+        None
+    }
+}
+
+impl From<&'static str> for Error {
+    fn from(string: &'static str) -> Error {
+        Client(string)
+    }
+}

src/transport/stub/mod.rs

@@ -0,0 +1,28 @@
+//! This transport is a stub that only logs the message, and always returns
+//! success
+
+use email::SendableEmail;
+use transport::EmailTransport;
+
+pub mod error;
+
+/// This transport does nothing except logging the message envelope
+pub struct StubEmailTransport;
+
+/// SMTP result type
+pub type StubResult = Result<(), error::Error>;
+
+impl EmailTransport<StubResult> for StubEmailTransport {
+    fn send<T: SendableEmail>(&mut self, email: T) -> StubResult {
+
+        info!("{}: from=<{}> to=<{:?}>",
+              email.message_id(),
+              email.from_address(),
+              email.to_addresses());
+        Ok(())
+    }
+
+    fn close(&mut self) {
+        ()
+    }
+}

tests/lib.rs

@@ -1,14 +1,5 @@
-// Copyright 2014 Alexis Mousset. See the COPYRIGHT
-// file at the top-level directory of this distribution.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
+extern crate lettre;
 
-#[test]
-
-fn foo() {
-    assert!(true);
-}
+mod transport_smtp;
+mod transport_stub;
+mod transport_file;

tests/transport_file.rs

@@ -0,0 +1,37 @@
+extern crate lettre;
+
+use std::env::temp_dir;
+use std::fs::File;
+use std::fs::remove_file;
+use std::io::Read;
+
+use lettre::transport::file::FileEmailTransport;
+use lettre::transport::EmailTransport;
+use lettre::email::{EmailBuilder, SendableEmail};
+
+#[test]
+fn file_transport() {
+    let mut sender = FileEmailTransport::new(temp_dir());
+    let email = EmailBuilder::new()
+                    .to("root@localhost")
+                    .from("user@localhost")
+                    .body("Hello World!")
+                    .subject("Hello")
+                    .build()
+                    .unwrap();
+    let result = sender.send(email.clone());
+    assert!(result.is_ok());
+
+    let message_id = email.message_id();
+    let file = format!("{}/{}.txt", temp_dir().to_str().unwrap(), message_id);
+    let mut f = File::open(file.clone()).unwrap();
+    let mut buffer = String::new();
+    let _ = f.read_to_string(&mut buffer);
+
+    assert_eq!(buffer,
+               format!("{}: from=<user@localhost> to=<root@localhost>\n{}",
+                       message_id,
+                       email.message()));
+
+    remove_file(file).unwrap();
+}

tests/transport_smtp.rs

@@ -0,0 +1,19 @@
+extern crate lettre;
+
+use lettre::transport::smtp::SmtpTransportBuilder;
+use lettre::transport::EmailTransport;
+use lettre::email::EmailBuilder;
+
+#[test]
+fn smtp_transport_simple() {
+    let mut sender = SmtpTransportBuilder::localhost().unwrap().build();
+    let email = EmailBuilder::new()
+                    .to("root@localhost")
+                    .from("user@localhost")
+                    .body("Hello World!")
+                    .subject("Hello")
+                    .build()
+                    .unwrap();
+    let result = sender.send(email);
+    assert!(result.is_ok());
+}

tests/transport_stub.rs

@@ -0,0 +1,19 @@
+extern crate lettre;
+
+use lettre::transport::stub::StubEmailTransport;
+use lettre::transport::EmailTransport;
+use lettre::email::EmailBuilder;
+
+#[test]
+fn stub_transport() {
+    let mut sender = StubEmailTransport;
+    let email = EmailBuilder::new()
+                    .to("root@localhost")
+                    .from("user@localhost")
+                    .body("Hello World!")
+                    .subject("Hello")
+                    .build()
+                    .unwrap();
+    let result = sender.send(email);
+    assert!(result.is_ok());
+}