Remove SSO_ACCOUNT_ID from scrubber docs and BucketConfig (#7774)

As of #6202 we support `AWS_PROFILE` as well, which is more convenient.
Change the docs to using it instead of `SSO_ACCOUNT_ID`. Also, remove
`SSO_ACCOUNT_ID` from BucketConfig as it is confusing to the code's
reader: it's not the "main" way of setting up authentication for the
scrubber any more.

It is a breaking change for the on-disk format as we persist `sso_account_id` to disk,
but it was quite inconsistent with the other methods which are not persistet. Also,
I don't think we want to support the case where one version writes the json and
another version reads it.

Related: #7667

s3_scrubber/README.md

@@ -9,11 +9,13 @@ and `safekeeper`, and does housekeeping such as cleaning up objects for tenants
 
 #### S3
 
-Do `aws sso login --profile dev` to get the SSO access to the bucket to clean, get the SSO_ACCOUNT_ID for your profile (`cat ~/.aws/config` may help).
+Do `aws sso login --profile dev` to get the SSO access to the bucket to clean.
+Also, set the following environment variables:
 
-- `SSO_ACCOUNT_ID`: Credentials id to use for accessing S3 buckets
+- `AWS_PROFILE`: Profile name to use for accessing S3 buckets (e.g. `dev`)
 - `REGION`: A region where the bucket is located at.
 - `BUCKET`: Bucket name
+- `BUCKET_PREFIX` (optional): Prefix inside the bucket
 
 #### Console API
 
@@ -43,7 +45,7 @@ processing by the `purge-garbage` subcommand.
 
 Example:
 
-`env SSO_ACCOUNT_ID=123456 REGION=eu-west-1 BUCKET=my-dev-bucket CLOUD_ADMIN_API_TOKEN=${NEON_CLOUD_ADMIN_API_STAGING_KEY} CLOUD_ADMIN_API_URL=[url] cargo run --release -- find-garbage --node-kind=pageserver --depth=tenant --output-path=eu-west-1-garbage.json`
+`env AWS_PROFILE=dev REGION=eu-west-1 BUCKET=my-dev-bucket CLOUD_ADMIN_API_TOKEN=${NEON_CLOUD_ADMIN_API_STAGING_KEY} CLOUD_ADMIN_API_URL=[url] cargo run --release -- find-garbage --node-kind=pageserver --depth=tenant --output-path=eu-west-1-garbage.json`
 
 #### `purge-garbage`
 
@@ -59,7 +61,7 @@ to pass them on the command line
 
 Example:
 
-`env SSO_ACCOUNT_ID=123456 cargo run --release -- purge-garbage --node-kind=pageserver --depth=tenant --input-path=eu-west-1-garbage.json`
+`env AWS_PROFILE=dev cargo run --release -- purge-garbage --node-kind=pageserver --depth=tenant --input-path=eu-west-1-garbage.json`
 
 Add the `--delete` argument before `purge-garbage` to enable deletion.  This is intentionally
 not provided inline in the example above to avoid accidents.  Without the `--delete` flag
@@ -72,7 +74,7 @@ Errors are logged to stderr and summary to stdout.
 
 For pageserver:
 ```
-env SSO_ACCOUNT_ID=123456 REGION=eu-west-1 BUCKET=my-dev-bucket CLOUD_ADMIN_API_TOKEN=${NEON_CLOUD_ADMIN_API_STAGING_KEY} CLOUD_ADMIN_API_URL=[url] cargo run --release -- scan-metadata --node-kind pageserver
+env AWS_PROFILE=dev REGION=eu-west-1 BUCKET=my-dev-bucket CLOUD_ADMIN_API_TOKEN=${NEON_CLOUD_ADMIN_API_STAGING_KEY} CLOUD_ADMIN_API_URL=[url] cargo run --release -- scan-metadata --node-kind pageserver
 
 Timelines: 31106
 With errors: 3

s3_scrubber/src/lib.rs

@@ -200,30 +200,15 @@ impl RootTarget {
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(deny_unknown_fields)]
 pub struct BucketConfig {
     pub region: String,
     pub bucket: String,
     pub prefix_in_bucket: Option<String>,
-
-    /// Use SSO if this is set, else rely on AWS_* environment vars
-    pub sso_account_id: Option<String>,
-}
-
-impl Display for BucketConfig {
-    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        write!(
-            f,
-            "{}/{}/{}",
-            self.sso_account_id.as_deref().unwrap_or("<none>"),
-            self.region,
-            self.bucket
-        )
-    }
 }
 
 impl BucketConfig {
     pub fn from_env() -> anyhow::Result<Self> {
-        let sso_account_id = env::var("SSO_ACCOUNT_ID").ok();
         let region = env::var("REGION").context("'REGION' param retrieval")?;
         let bucket = env::var("BUCKET").context("'BUCKET' param retrieval")?;
         let prefix_in_bucket = env::var("BUCKET_PREFIX").ok();
@@ -232,7 +217,6 @@ impl BucketConfig {
             region,
             bucket,
             prefix_in_bucket,
-            sso_account_id,
         })
     }
 }
@@ -276,7 +260,7 @@ pub fn init_logging(file_name: &str) -> WorkerGuard {
     guard
 }
 
-pub fn init_s3_client(account_id: Option<String>, bucket_region: Region) -> Client {
+pub fn init_s3_client(bucket_region: Region) -> Client {
     let credentials_provider = {
         // uses "AWS_ACCESS_KEY_ID", "AWS_SECRET_ACCESS_KEY"
         let chain = CredentialsProviderChain::first_try(
@@ -290,7 +274,7 @@ pub fn init_s3_client(account_id: Option<String>, bucket_region: Region) -> Clie
         );
 
         // Use SSO if we were given an account ID
-        match account_id {
+        match std::env::var("SSO_ACCOUNT_ID").ok() {
             Some(sso_account) => chain.or_else(
                 "sso",
                 SsoCredentialsProvider::builder()
@@ -334,7 +318,7 @@ fn init_remote(
 ) -> anyhow::Result<(Arc<Client>, RootTarget)> {
     let bucket_region = Region::new(bucket_config.region);
     let delimiter = "/".to_string();
-    let s3_client = Arc::new(init_s3_client(bucket_config.sso_account_id, bucket_region));
+    let s3_client = Arc::new(init_s3_client(bucket_region));
 
     let s3_root = match node_kind {
         NodeKind::Pageserver => RootTarget::Pageserver(S3Target {