Struct Cache 

pub struct Cache<B, C, CM, O = DisabledOffload> {
    pub backend: Arc<B>,
    pub configuration: C,
    pub offload: O,
    pub concurrency_manager: CM,
    pub cache_status_header: HeaderName,
}

Tower Layer that adds HTTP caching to a service.

Cache wraps any Tower service with caching behavior. When a request arrives, the layer evaluates predicates to determine cacheability, generates a cache key using extractors, and either returns a cached response or forwards to the upstream service.

Type Parameters

• B - Cache backend (e.g., MokaBackend, RedisBackend). Must implement CacheBackend.
• C - Configuration providing predicates, extractors, and policy. Use hitbox::Config to build custom configuration.
• CM - Concurrency manager for dogpile prevention. Use NoopConcurrencyManager to disable or BroadcastConcurrencyManager to enable.
• O - Offload strategy for background revalidation. Use DisabledOffload for synchronous behavior.

Examples

Create with the builder pattern:

use hitbox_tower::Cache;
use hitbox_moka::MokaBackend;
use hitbox::Config;
use hitbox_http::extractors::Method;
use hitbox_http::predicates::{NeutralRequestPredicate, NeutralResponsePredicate};

let config = Config::builder()
    .request_predicate(NeutralRequestPredicate::new())
    .response_predicate(NeutralResponsePredicate::new())
    .extractor(Method::new())
    .build();

let cache_layer = Cache::builder()
    .backend(MokaBackend::builder().max_entries(1000).build())
    .config(config)
    .build();

Fields

backend: Arc<B>

The cache backend for storing and retrieving responses.

configuration: C

Configuration with predicates, extractors, and cache policy.

offload: O

Offload strategy for background tasks.

concurrency_manager: CM

Concurrency manager for dogpile prevention.

cache_status_header: HeaderName

Header name for cache status (HIT/MISS/STALE).

Implementations

impl Cache<NotSet, NotSet, NoopConcurrencyManager, DisabledOffload>

pub fn builder() -> CacheBuilder<NotSet, NotSet, NoopConcurrencyManager, DisabledOffload>

Creates a new CacheBuilder.

Both backend() and config() must be called before build().

Examples

use hitbox_tower::Cache;
use hitbox_moka::MokaBackend;
use hitbox::Config;
use hitbox_http::extractors::Method;
use hitbox_http::predicates::{NeutralRequestPredicate, NeutralResponsePredicate};

let config = Config::builder()
    .request_predicate(NeutralRequestPredicate::new())
    .response_predicate(NeutralResponsePredicate::new())
    .extractor(Method::new())
    .build();

let cache_layer = Cache::builder()
    .backend(MokaBackend::builder().max_entries(1000).build())
    .config(config)
    .build();

Trait Implementations

impl<B: Clone, C: Clone, CM: Clone, O: Clone> Clone for Cache<B, C, CM, O>

fn clone(&self) -> Cache<B, C, CM, O>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<S, B, C, CM, O> Layer<S> for Cache<B, C, CM, O>

where C: Clone, CM: Clone, O: Clone,

type Service = CacheService<S, B, C, CM, O>

The wrapped service

fn layer(&self, upstream: S) -> Self::Service

Wrap the given service with the middleware, returning a new service that has been decorated with the middleware.