Struct RunExportsCache 

pub struct RunExportsCache { /* private fields */ }

A RunExportsCache manages a cache of run_exports.json

The store does not provide an implementation to get the data into the store. Instead, this is left up to the user when the run_exports.json is requested. If the run_exports.json is found in the cache it is returned immediately. However, if the cache is missing a user defined function is called to populate the cache. This separates the corners between caching and fetching of the content.

Implementations

impl RunExportsCache

pub fn new(path: impl Into<PathBuf>) -> Self

Constructs a new RunExportsCache located at the specified path.

pub async fn get_or_fetch<F, Fut, E>( &self, cache_key: &CacheKey, fetch: F, ) -> Result<CacheEntry, RunExportsCacheError>

where F: Fn() -> Fut + Send + 'static, Fut: Future<Output = Result<Option<NamedTempFile>, E>> + Send + 'static, E: Error + Send + Sync + 'static,

Returns the directory that contains the specified package.

If the package was previously successfully fetched and stored in the cache the directory containing the data is returned immediately. If the package was not previously fetch the filesystem is checked to see if a directory with valid package content exists. Otherwise, the user provided fetch function is called to populate the cache.

If the package is already being fetched by another task/thread the request is coalesced. No duplicate fetch is performed.

pub async fn get_or_fetch_from_url( &self, cache_key: &CacheKey, url: Url, client: ClientWithMiddleware, reporter: Option<Arc<dyn CacheReporter>>, ) -> Result<CacheEntry, RunExportsCacheError>

Returns the directory that contains the specified package.

This is a convenience wrapper around get_or_fetch which fetches the package from the given URL if the package could not be found in the cache.

pub async fn get_or_fetch_from_url_with_retry( &self, cache_key: &CacheKey, url: Url, client: ClientWithMiddleware, retry_policy: impl RetryPolicy + Send + 'static + Clone, reporter: Option<Arc<dyn CacheReporter>>, ) -> Result<CacheEntry, RunExportsCacheError>

Returns the directory that contains the specified package.

This is a convenience wrapper around get_or_fetch which fetches the package from the given URL if the package could not be found in the cache.

This function assumes that the client is already configured with a retry middleware that will retry any request that fails. This function uses the passed in retry_policy if, after the request has been sent and the response is successful, streaming of the package data fails and the whole request must be retried.

Trait Implementations

impl Clone for RunExportsCache

fn clone(&self) -> RunExportsCache

Returns a duplicate of the value.

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

Performs copy-assignment from source.