Struct Cache 

pub struct Cache { /* private fields */ }

The cache is a key-value store shared across Wasm instances. As Wasm is single threaded, the gateway uses a pool of Wasm instances to execute extensions. Cache with the same name will be the same across those instances and share the same data.

Implementations

impl Cache

pub fn builder(name: impl Into<Cow<'static, str>>, size: usize) -> CacheBuilder

Creates a new cache builder with the given name and size. Caches are unique for a given name and extension.

pub fn get_or_insert_bytes( &self, key: &str, f: impl FnOnce() -> Vec<u8>, ) -> Vec<u8>

Retrieves a value from the cache by key or initialize it with the provided function using the default timeout. If you need to additional validation on the bytes before storing it in the cache, consider using get_or_insert can keep additional state. If you need error handling, use try_get_or_insert_bytes.

See try_get_or_insert_with_timeout for more details

pub fn get_or_insert_bytes_with_timeout( &self, key: &str, timeout: Duration, f: impl FnOnce() -> Vec<u8>, ) -> Vec<u8>

Retrieves a value from the cache by key or initialize it with the provided function using the default timeout. If you need to additional validation on the bytes before storing it in the cache, consider using get_or_insert_with_timeout can keep additional state. If you need error handling, use try_get_or_insert_bytes_with_timeout.

See try_get_or_insert_with_timeout for more details

pub fn get_or_insert<T>( &self, key: &str, f: impl FnOnce() -> (T, Vec<u8>), ) -> (Option<T>, Vec<u8>)

Retrieves a value from the cache by key or initialize it with the provided function using the default timeout.get_or_insert_bytes is a simpler variant if you only handle bytes. If you need error handling, use try_get_or_insert.

See try_get_or_insert_with_timeout for more details

pub fn get_or_insert_with_timeout<T>( &self, key: &str, timeout: Duration, f: impl FnOnce() -> (T, Vec<u8>), ) -> (Option<T>, Vec<u8>)

Retrieves a value from the cache by key or initialize it with the provided function using the default timeout.get_or_insert_bytes_with_timeout is a simpler variant if you only handle bytes. If you need error handling, use try_get_or_insert_with_timeout.

See try_get_or_insert_with_timeout for more details

pub fn try_get_or_insert_bytes<E>( &self, key: &str, f: impl FnOnce() -> Result<Vec<u8>, E>, ) -> Result<Vec<u8>, E>

Retrieves a value from the cache by key or initialize it with the provided function using the default timeout. See try_get_or_insert_with_timeout for more details

pub fn try_get_or_insert_bytes_with_timeout<E>( &self, key: &str, timeout: Duration, f: impl FnOnce() -> Result<Vec<u8>, E>, ) -> Result<Vec<u8>, E>

Retrieves a value from the cache by key or initialize it with the provided function using the default timeout. See try_get_or_insert_with_timeout for more details

pub fn try_get_or_insert<T, E>( &self, key: &str, f: impl FnOnce() -> Result<(T, Vec<u8>), E>, ) -> Result<(Option<T>, Vec<u8>), E>

Retrieves a value from the cache by key or initialize it with the provided function using the default timeout. See try_get_or_insert_with_timeout for more details

pub fn try_get_or_insert_with_timeout<T, E>( &self, key: &str, timeout: Duration, f: impl FnOnce() -> Result<(T, Vec<u8>), E>, ) -> Result<(Option<T>, Vec<u8>), E>

Retrieves a value from the cache by key or initialize it with the provided function. If there is no existing value in the cache, the callback function will be immediately called to fill the cache. All further calls during the callback execution will wait for the value to be computed. As the callback might crash, a timeout limits how long this function will wait. Unfortunately it does result in a thundering herd problem where all Wasm instances will try to compute the value at the same time.