Struct TokenSourceCached 

pub struct TokenSourceCached<S> { /* private fields */ }

The return type of TokenSourceConfigurable::cached: wraps another token source and stores the last fetched credentials, serving them for repeat fetches with equal options for as long as they stay valid.

Credentials are kept in a TokenSourceStore (by default in memory, see TokenSourceCached::with_store) and are considered valid as long as a validator accepts them (by default until the token expires, see TokenSourceCached::with_validator).

Concurrent fetches that miss the cache are not deduplicated; each hits the underlying source and the last response wins.

Implementations

impl<S> TokenSourceCached<S>

pub fn with_store(self, store: impl TokenSourceStore + 'static) -> Self

Replaces the default in-memory store with a custom TokenSourceStore, e.g. one persisting credentials to the platform keychain or a database.

pub fn with_validator<F>(self, validator: F) -> Self

where F: Fn(&TokenSourceFetchOptions, &TokenSourceResponse) -> bool + Send + Sync + 'static,

Replaces the default validator deciding whether stored credentials are still valid or must be refetched. The default checks that the token has not expired (TokenSourceResponse::has_valid_token).

Pass the closure inline (or annotate its parameter types); binding it to a variable first can fail closure type inference.

pub async fn invalidate(&self)

Removes the stored credentials, forcing the next fetch to hit the underlying source.

A fetch already in flight is unaffected: it still resolves and stores its response afterwards, repopulating the cache (last writer wins).

pub async fn cached_response(&self) -> Option<TokenSourceResponse>

Returns the last stored response, if any — without checking its validity or which options it was fetched with, so it may be expired.

Trait Implementations

impl<S: TokenSourceConfigurable + Send + Sync> TokenSourceConfigurable for TokenSourceCached<S>

fn fetch<'life0, 'life1, 'async_trait>( &'life0 self, options: &'life1 TokenSourceFetchOptions, ) -> Pin<Box<dyn Future<Output = TokenSourceResult<TokenSourceResponse>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

fn cached(self) -> TokenSourceCached<Self>

where Self: Sized + Send + Sync,

Wraps this source in a caching layer that stores the last fetched credentials and serves them for repeat fetches with equal options, for as long as the token stays valid. See TokenSourceCached.