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EndpointResolver

toolkit::discovery

Trait EndpointResolver 

Source 
pub trait EndpointResolver: Send + Sync {
    // Required method
    fn resolve_endpoint<'life0, 'life1, 'async_trait>(
        &'life0 self,
        gear: &'life1 str,
    ) -> Pin<Box<dyn Future<Output = Result<Option<String>, ResolveError>> + Send + 'async_trait>>
       where 'life0: 'async_trait,
             'life1: 'async_trait,
             Self: 'async_trait;
}
Expand description

Re-export so the #[toolkit::consumes]-generated wire fn can name the resolver type as toolkit::discovery::EndpointResolver without the consuming gear crate needing a direct toolkit-contract dependency. Resolves a logical gear name to a live base endpoint URI.

Kept as a minimal trait here so toolkit-contract does not depend on the service-directory SDK. The host layer (toolkit) provides an adapter over its DirectoryClient; tests can implement it directly.

Return contract:

  • Ok(Some(uri)) — a live instance was resolved.
  • Ok(None) — the lookup succeeded but no live instance is registered (provider not ready yet, or every instance evicted).
  • Err(ResolveError) — the directory backend itself failed to answer.

Both Ok(None) and Err(..) surface to the caller as a retryable TransportError::Unresolved; the distinction exists for logging/metrics.

DirectoryResolvingClient calls this on every request so provider churn is observed immediately. Implementations whose lookup is expensive (e.g. an out-of-process gRPC directory) SHOULD memoize internally (short TTL) rather than performing a network round-trip per call.

Required Methods§

Source

fn resolve_endpoint<'life0, 'life1, 'async_trait>( &'life0 self, gear: &'life1 str, ) -> Pin<Box<dyn Future<Output = Result<Option<String>, ResolveError>> + Send + 'async_trait>>
where 'life0: 'async_trait, 'life1: 'async_trait, Self: 'async_trait,

Resolve gear to a base endpoint URI (e.g. http://billing:8080).

§Errors

Returns ResolveError only when the directory backend could not be queried; a successful query with no live instance is Ok(None).

Dyn Compatibility§

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors§