penpot/backend/src/app/util/cache.clj
2024-01-25 15:59:45 +01:00

80 lines
2.4 KiB
Clojure

;; This Source Code Form is subject to the terms of the Mozilla Public
;; License, v. 2.0. If a copy of the MPL was not distributed with this
;; file, You can obtain one at http://mozilla.org/MPL/2.0/.
;;
;; Copyright (c) KALEIDOS INC
(ns app.util.cache
"In-memory cache backed by Caffeine"
(:refer-clojure :exclude [get])
(:require
[app.util.time :as dt]
[promesa.exec :as px])
(:import
com.github.benmanes.caffeine.cache.AsyncCache
com.github.benmanes.caffeine.cache.Cache
com.github.benmanes.caffeine.cache.Caffeine
com.github.benmanes.caffeine.cache.RemovalListener
com.github.benmanes.caffeine.cache.stats.CacheStats
java.time.Duration
java.util.concurrent.Executor
java.util.function.Function))
(set! *warn-on-reflection* true)
(defprotocol ICache
(get [_ k] [_ k load-fn] "get cache entry")
(invalidate! [_] [_ k] "invalidate cache"))
(defprotocol ICacheStats
(stats [_] "get stats"))
(defn- create-listener
[f]
(reify RemovalListener
(onRemoval [_ key val cause]
(when val
(f key val cause)))))
(defn- get-stats
[^Cache cache]
(let [^CacheStats stats (.stats cache)]
{:hit-rate (.hitRate stats)
:hit-count (.hitCount stats)
:req-count (.requestCount stats)
:miss-count (.missCount stats)
:miss-rate (.missRate stats)}))
(defn create
[& {:keys [executor on-remove max-size keepalive]}]
(let [cache (as-> (Caffeine/newBuilder) builder
(if (fn? on-remove) (.removalListener builder (create-listener on-remove)) builder)
(if executor (.executor builder ^Executor (px/resolve-executor executor)) builder)
(if keepalive (.expireAfterAccess builder ^Duration (dt/duration keepalive)) builder)
(if (int? max-size) (.maximumSize builder (long max-size)) builder)
(.recordStats builder)
(.buildAsync builder))
cache (.synchronous ^AsyncCache cache)]
(reify
ICache
(get [_ k]
(.getIfPresent ^Cache cache ^Object k))
(get [_ k load-fn]
(.get ^Cache cache
^Object k
^Function (reify Function
(apply [_ k]
(load-fn k)))))
(invalidate! [_]
(.invalidateAll ^Cache cache))
(invalidate! [_ k]
(.invalidateAll ^Cache cache ^Object k))
ICacheStats
(stats [_]
(get-stats cache)))))
(defn cache?
[o]
(satisfies? ICache o))