Module manager 

Path manager

A PathManager provides applications with SCION paths. The method PathManager::path_wait is an async implementation that possibly awaits asynchronous, external path requests before returning. The sync-equivalent is SyncPathManager::try_cached_path which returns immediately in all cases.

The main implementation provided in this module is the CachingPathManager which is an active component: CachingPathManager::start will start an asynchronous background task (via tokio::spawn) that fetches requested paths using the provided PathFetcher.

Typically, applications require paths to fulfill specific constraints and paths are ranked; i.e. some paths are preferred over others. In the case of the CachingPathManager such constraints are expressed via a PathPolicy: only paths that fulfill PathPolicy::predicate are returned and paths with a lower rank according to PathPolicy::rank are preferred.

Structs

CachingPathManager

Active path manager that runs as a background task

ConnectRpcSegmentFetcher

Connect RPC segment fetcher.

PathFetcherImpl

Path fetcher.

Segments

Path segments.

Enums

PathFetchError

Path fetch errors.

PathToError

Path fetch errors.

PathWaitError

Path wait errors.

Traits

PathFetcher

Path fetcher trait.

PathManager

Trait for active path management with async interface.

PathPrefetcher

Trait for prefetching paths in the path manager.

SegmentFetcher

Segment fetcher trait.

SyncPathManager

Trait for active path management with sync interface. Implementors of this trait should be able to be used in sync and async context. The functions must not block.

Type Aliases

SegmentFetchError

Segment fetch error.