// Declares a new entity cache limited to 10000 entries, with a 5 minutes time to refresh and a 10 minutes time to live. // It exposes a Prometheus metric named "entity_cache_hit_total" with the labels "namespace" and "hit". cache, err := entitycache.New(10000, 5*time.Minute, 10*time.Minute, "entity_cache_hit_total") if err != nil { panic(err) } // Let's say we want to cache the document with the ID 128. documentID := 128 document, ok, err := cache.Get(ctx, "documents", fmt.Sprintf("%d", documentID), func(ctx context.Context) (value interface{}, ok bool, err error) { document, err := getDocumentByID(ctx, documentID) if err != nil { if err == sql.ErrNoRows { return nil, false, nil } return nil, false, err } return document, true, nil })

// Declares a new entity cache limited to 10000 entries, with a 5 minutes time to refresh and a 10 minutes time to live. // It exposes a Prometheus metric named "entity_cache_hit_total" with the labels "namespace" and "hit". cache, err := entitycache.New(10000, 5*time.Minute, 10*time.Minute, "entity_cache_hit_total") if err != nil { panic(err) } // Let's say we want to cache the document with the ID 128. documentID := 128 // We also want it localized in french. language := "fr" // Our cache key would then be for example: key := fmt.Sprintf("%d-%s", documentID, language) // We additionally cache the document for an "any" key. // All the languages being requested will keep this entry warm. anyKey := fmt.Sprintf("%d-any", documentID) // We get the french document from the cache. document, ok, err := cache.MultiKeyGet(ctx, "documents", key, []string{anyKey}, func(ctx context.Context) (value interface{}, ok bool, err error) { if language == "any" { // We fallback to english by default. language = "en" } document, err := getDocumentByID(ctx, documentID, language) if err != nil { if err == sql.ErrNoRows { return nil, false, nil } return nil, false, err } return document, true, nil }) // A next call asking for an "any" language would opportunistically get a cached document, in whatever language laying in the cache.