Struct Supervisor 

pub struct Supervisor { /* private fields */ }

A minimal supervisor that coordinates shutdown and tracks child threads.

Blessed pattern:

• Create one Supervisor at process start.
• Spawn long-running threads with Supervisor::spawn_thread (or Supervisor::spawn_restartable_thread), and exit the thread when shutdown is requested.
• On shutdown (signal / admin request), call Supervisor::shutdown_and_join.

Error semantics

• A child thread that returns Err causes Supervisor::join_all to return Err.
• A child thread that panics also causes Supervisor::join_all to return Err. When multiple children fail, errors are aggregated into a single message.

Implementations

impl Supervisor

pub fn new(cfg: SupervisorConfig) -> Self

Create a new supervisor with the provided configuration.

Contract: configuration is validated when spawning children.

pub fn config(&self) -> SupervisorConfig

Get the supervisor configuration.

pub fn shutdown(&self) -> Shutdown

Access the supervisor’s shutdown coordinator.

pub fn token(&self) -> ShutdownToken

Convenience accessor for the supervisor shutdown token.

pub fn validate(&self) -> Result<()>

Validate the current configuration.

Errors: returns Error if the configuration is internally inconsistent.

pub fn spawn_thread<F>(&self, name: impl Into<String>, f: F) -> Result<()>

where F: FnOnce(ShutdownToken) -> Result<()> + Send + 'static,

Spawn a supervised thread.

Contract: the closure should return when it observes shutdown.

Errors:

• Returns an error if configuration validation fails.
• Returns an error if the OS thread cannot be spawned.

If the closure returns Err, Supervisor::join_all will return Err.

pub fn spawn_restartable_thread<F>( &self, name: impl Into<String>, f: F, ) -> Result<()>

where F: Fn(ShutdownToken) -> Result<()> + Send + Sync + 'static,

Spawn a supervised thread that will be restarted with backoff on error.

Contract:

• The child exits successfully if shutdown is requested.
• If the closure returns Err and shutdown is not requested, the supervisor sleeps for a backoff duration and retries.

Errors:

• Returns an error if configuration validation fails.
• Returns an error if the OS thread cannot be spawned.
• Returns an error if the child exceeds max_restarts.

pub fn join_all(&self) -> Result<()>

Join all supervised children.

Contract: this drains the supervisor’s child list. A subsequent call will join zero children and return Ok(()).

Errors:

• If any child returns an error, returns an aggregated Error.
• If any child panics, returns an aggregated Error.

pub fn shutdown_and_join(&self) -> Result<()>

Convenience: trigger shutdown and then join all children.

Contract: this is equivalent to calling Shutdown::trigger and then Supervisor::join_all.

Trait Implementations

impl Clone for Supervisor

fn clone(&self) -> Supervisor

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.