Trait StatefulService 

pub trait StatefulService: MockService {
    type StateView: Serialize + DeserializeOwned + Send + Sync;

    // Required methods
    async fn snapshot(&self, account_id: &str, region: &str) -> Self::StateView;
    async fn restore(
        &self,
        account_id: &str,
        region: &str,
        view: Self::StateView,
    ) -> Result<(), StateViewError>;
    async fn merge(
        &self,
        account_id: &str,
        region: &str,
        view: Self::StateView,
    ) -> Result<(), StateViewError>;
    fn notifier(&self) -> &StateChangeNotifier<Self::StateView>;

    // Provided method
    async fn notify_state_changed(&self, account_id: &str, region: &str) { ... }
}

A service that exposes typed, serde-compatible views of its internal state.

Each service implements this trait with a StateView type that is a serde-friendly representation of its internal state. The view types are separate from the internal types to decouple serialization from implementation.

Example

// Take a snapshot of S3 state
let view: S3StateView = s3_service.snapshot("123456789012", "us-east-1");

// Serialize to JSON
let json = serde_json::to_string_pretty(&view).unwrap();

// Restore from a view
let view: S3StateView = serde_json::from_str(&json).unwrap();
s3_service.restore("123456789012", "us-east-1", view).unwrap();

Required Associated Types

type StateView: Serialize + DeserializeOwned + Send + Sync

Serde-compatible view of this service’s per-region state.

Required Methods

async fn snapshot(&self, account_id: &str, region: &str) -> Self::StateView

Take a snapshot of the state for the given account/region as a typed view.

async fn restore( &self, account_id: &str, region: &str, view: Self::StateView, ) -> Result<(), StateViewError>

Restore state for the given account/region from a typed view. Replaces the existing state entirely.

async fn merge( &self, account_id: &str, region: &str, view: Self::StateView, ) -> Result<(), StateViewError>

Merge a partial view into existing state (additive, does not remove existing resources).

fn notifier(&self) -> &StateChangeNotifier<Self::StateView>

Returns the state-change notifier embedded in this service.

Implement by returning a reference to a StateChangeNotifier field on the service struct.

Provided Methods

async fn notify_state_changed(&self, account_id: &str, region: &str)

Take a snapshot of the given account/region and forward it to all registered listeners. Call this after any successful state mutation.

The write lock on the state must be released before calling this method to avoid a deadlock (snapshot acquires a read lock).

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors