Struct Cache 

pub struct Cache { /* private fields */ }

A handle on the cache database plus the active mode and TTLs. Cheap to clone (clones share one connection); clone it out of the Context to use get_or_fetch with a closure that borrows the context. The database is opened on first use.

Implementations

impl Cache

pub fn index_restaurants( &self, rows: &[RestaurantRow], seen_from: Option<(f64, f64)>, ) -> Result<()>

Upsert restaurants seen in a list response. seen_from is the delivery location of the request; when given, each row’s distance / ETA / fee are also recorded for that location. No-op when writes are off.

pub fn index_restaurants_at( &self, rows: &[RestaurantRow], seen_from: Option<(f64, f64)>, now: i64, ) -> Result<()>

pub fn index_items(&self, items: &[ItemRow]) -> Result<()>

Upsert individual items (e.g. dish hits in search results), keeping any category already known. No-op when writes are off.

pub fn index_items_at(&self, items: &[ItemRow], now: i64) -> Result<()>

pub fn index_menu( &self, restaurant: &RestaurantRow, categories: &[CategoryRow], items: &[ItemRow], seen_from: Option<(f64, f64)>, ) -> Result<()>

Store a full menu: the restaurant, its categories (replacing the old ones) and items; items no longer on the menu are removed. No-op when writes are off.

pub fn index_menu_at( &self, restaurant: &RestaurantRow, categories: &[CategoryRow], items: &[ItemRow], seen_from: Option<(f64, f64)>, now: i64, ) -> Result<()>

pub fn search_restaurants( &self, q: &RestaurantQuery, ) -> Result<Vec<RestaurantHit>>

Query restaurants in the catalog (works in every mode: it only reads what earlier fetches stored).

pub fn search_items(&self, q: &ItemQuery) -> Result<Vec<ItemHit>>

Query menu items in the catalog.

pub fn restaurant(&self, id: &str) -> Result<Option<RestaurantHit>>

One restaurant by id.

impl Cache

pub fn cached_image(&self, url: &str) -> Option<CachedImage>

The cached file for url, if present (and still on disk). Marks it recently used.

pub fn store_image( &self, url: &str, bytes: &[u8], content_type: &str, ) -> Result<CachedImage>

Store downloaded image bytes for url (dedupes by content hash), then evict over the size cap.

pub fn store_image_at( &self, url: &str, bytes: &[u8], content_type: &str, now: i64, ) -> Result<CachedImage>

pub async fn fetch_image(&self, url: &str) -> Result<CachedImage>

The cached file for url, downloading it first if needed. Only Grab CDN URLs are fetched (image_url_allowed); no cookies are sent.

impl Cache

pub fn new( root: impl Into<PathBuf>, config: CacheConfig, mode: CacheMode, ) -> Self

A cache rooted at root (the database is root/cache.sqlite). config.enabled == false forces CacheMode::Off.

pub fn from_config(config: &CacheConfig, mode: CacheMode) -> Self

The production cache: paths::cache_dir, the [cache] config, and GRAB_NO_CACHE=1 forcing it off. If the cache dir can’t be resolved the cache is simply off.

pub fn with_mode(&self, mode: CacheMode) -> Self

The same cache (sharing its connection) with another mode; still off if disabled in config.

pub fn mode(&self) -> CacheMode

pub fn root(&self) -> &Path

The cache directory.

pub fn db_path(&self) -> PathBuf

pub fn config(&self) -> &CacheConfig

pub fn ttl(&self, kind: CacheKind) -> u64

pub fn get<T: DeserializeOwned>(&self, key: &CacheKey) -> Option<T>

A fresh cached value, if reads are enabled and one exists. Any problem reading or decoding the entry is a miss.

pub fn lookup<T: DeserializeOwned>(&self, key: &CacheKey) -> Option<Fetched<T>>

Like get, with the time the entry was fetched.

pub fn lookup_stale<T: DeserializeOwned>( &self, key: &CacheKey, ) -> Option<Fetched<T>>

The stored value for key even if it has expired (but not yet been pruned), for falling back when the live call fails. None when the mode is off.

pub fn put<T: Serialize>(&self, key: &CacheKey, value: &T) -> Result<()>

Store a value (no-op when writes are off or the kind’s TTL is 0).

pub async fn get_or_fetch<T, F, Fut>( &self, key: &CacheKey, fetch: F, ) -> Result<T>

where T: Serialize + DeserializeOwned, F: FnOnce() -> Fut, Fut: Future<Output = Result<T>>,

Return the cached value for key, or run fetch, store its result (best-effort) and return it. Errors from fetch are returned and never cached. Prefer T = serde_json::Value holding the raw upstream response.

pub async fn get_or_fetch_meta<T, F, Fut>( &self, key: &CacheKey, fetch: F, ) -> Result<Fetched<T>>

where T: Serialize + DeserializeOwned, F: FnOnce() -> Fut, Fut: Future<Output = Result<T>>,

get_or_fetch that also says whether the value came from the cache and how old it is.

pub fn stats(&self) -> Result<CacheStats>

pub fn clear(&self, kind: Option<CacheKind>, expired_only: bool) -> Result<u64>

Remove response entries, optionally only of one kind and/or only expired ones. Returns how many were removed. Catalog rows and images are kept (see clear_all / prune).

pub fn clear_all(&self) -> Result<ClearReport>

Remove everything: responses, catalog rows and image files.

pub fn prune(&self) -> Result<PruneReport>

Housekeeping: drop expired responses, catalog rows older than index_max_age_days, and evict images over image_max_mb (LRU), then compact the database.

Trait Implementations

impl Clone for Cache

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Cache

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.