neon_local: Use clap derive macros to parse the CLI args (#9103)

This is easier to work with.

control_plane/src/branch_mappings.rs

@@ -0,0 +1,94 @@
+//! Branch mappings for convenience
+
+use std::collections::HashMap;
+use std::fs;
+use std::path::Path;
+
+use anyhow::{bail, Context};
+use serde::{Deserialize, Serialize};
+
+use utils::id::{TenantId, TenantTimelineId, TimelineId};
+
+/// Keep human-readable aliases in memory (and persist them to config XXX), to hide tenant/timeline hex strings from the user.
+#[derive(PartialEq, Eq, Clone, Debug, Default, Serialize, Deserialize)]
+#[serde(default, deny_unknown_fields)]
+pub struct BranchMappings {
+    /// Default tenant ID to use with the 'neon_local' command line utility, when
+    /// --tenant_id is not explicitly specified. This comes from the branches.
+    pub default_tenant_id: Option<TenantId>,
+
+    // A `HashMap<String, HashMap<TenantId, TimelineId>>` would be more appropriate here,
+    // but deserialization into a generic toml object as `toml::Value::try_from` fails with an error.
+    // https://toml.io/en/v1.0.0 does not contain a concept of "a table inside another table".
+    pub mappings: HashMap<String, Vec<(TenantId, TimelineId)>>,
+}
+
+impl BranchMappings {
+    pub fn register_branch_mapping(
+        &mut self,
+        branch_name: String,
+        tenant_id: TenantId,
+        timeline_id: TimelineId,
+    ) -> anyhow::Result<()> {
+        let existing_values = self.mappings.entry(branch_name.clone()).or_default();
+
+        let existing_ids = existing_values
+            .iter()
+            .find(|(existing_tenant_id, _)| existing_tenant_id == &tenant_id);
+
+        if let Some((_, old_timeline_id)) = existing_ids {
+            if old_timeline_id == &timeline_id {
+                Ok(())
+            } else {
+                bail!("branch '{branch_name}' is already mapped to timeline {old_timeline_id}, cannot map to another timeline {timeline_id}");
+            }
+        } else {
+            existing_values.push((tenant_id, timeline_id));
+            Ok(())
+        }
+    }
+
+    pub fn get_branch_timeline_id(
+        &self,
+        branch_name: &str,
+        tenant_id: TenantId,
+    ) -> Option<TimelineId> {
+        // If it looks like a timeline ID, return it as it is
+        if let Ok(timeline_id) = branch_name.parse::<TimelineId>() {
+            return Some(timeline_id);
+        }
+
+        self.mappings
+            .get(branch_name)?
+            .iter()
+            .find(|(mapped_tenant_id, _)| mapped_tenant_id == &tenant_id)
+            .map(|&(_, timeline_id)| timeline_id)
+            .map(TimelineId::from)
+    }
+
+    pub fn timeline_name_mappings(&self) -> HashMap<TenantTimelineId, String> {
+        self.mappings
+            .iter()
+            .flat_map(|(name, tenant_timelines)| {
+                tenant_timelines.iter().map(|&(tenant_id, timeline_id)| {
+                    (TenantTimelineId::new(tenant_id, timeline_id), name.clone())
+                })
+            })
+            .collect()
+    }
+
+    pub fn persist(&self, path: &Path) -> anyhow::Result<()> {
+        let content = &toml::to_string_pretty(self)?;
+        fs::write(path, content).with_context(|| {
+            format!(
+                "Failed to write branch information into path '{}'",
+                path.display()
+            )
+        })
+    }
+
+    pub fn load(path: &Path) -> anyhow::Result<BranchMappings> {
+        let branches_file_contents = fs::read_to_string(path)?;
+        Ok(toml::from_str(branches_file_contents.as_str())?)
+    }
+}

control_plane/src/safekeeper.rs

@@ -113,7 +113,7 @@ impl SafekeeperNode {
 
     pub async fn start(
         &self,
-        extra_opts: Vec<String>,
+        extra_opts: &[String],
         retry_timeout: &Duration,
     ) -> anyhow::Result<()> {
         print!(
@@ -196,7 +196,7 @@ impl SafekeeperNode {
             ]);
         }
 
-        args.extend(extra_opts);
+        args.extend_from_slice(extra_opts);
 
         background_process::start_process(
             &format!("safekeeper-{id}"),