first-commit

modules/cache/cache.go

@@ -0,0 +1,119 @@
+// Copyright 2017 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package cache
+
+import (
+	"encoding/hex"
+	"errors"
+	"fmt"
+	"strconv"
+	"time"
+
+	"code.gitea.io/gitea/modules/setting"
+
+	_ "gitea.com/go-chi/cache/memcache" //nolint:depguard // memcache plugin for cache, it is required for config "ADAPTER=memcache"
+)
+
+var defaultCache StringCache
+
+// Init start cache service
+func Init() error {
+	if defaultCache == nil {
+		c, err := NewStringCache(setting.CacheService.Cache)
+		if err != nil {
+			return err
+		}
+		for range 10 {
+			if err = c.Ping(); err == nil {
+				break
+			}
+			time.Sleep(time.Second)
+		}
+		if err != nil {
+			return err
+		}
+		defaultCache = c
+	}
+	return nil
+}
+
+const (
+	testCacheKey = "DefaultCache.TestKey"
+	// SlowCacheThreshold marks cache tests as slow
+	// set to 30ms per discussion: https://github.com/go-gitea/gitea/issues/33190
+	// TODO: Replace with metrics histogram
+	SlowCacheThreshold = 30 * time.Millisecond
+)
+
+// Test performs delete, put and get operations on a predefined key
+// returns
+func Test() (time.Duration, error) {
+	if defaultCache == nil {
+		return 0, errors.New("default cache not initialized")
+	}
+
+	testData := hex.EncodeToString(make([]byte, 500))
+
+	start := time.Now()
+
+	if err := defaultCache.Delete(testCacheKey); err != nil {
+		return 0, fmt.Errorf("expect cache to delete data based on key if exist but got: %w", err)
+	}
+	if err := defaultCache.Put(testCacheKey, testData, 10); err != nil {
+		return 0, fmt.Errorf("expect cache to store data but got: %w", err)
+	}
+	testVal, hit := defaultCache.Get(testCacheKey)
+	if !hit {
+		return 0, errors.New("expect cache hit but got none")
+	}
+	if testVal != testData {
+		return 0, errors.New("expect cache to return same value as stored but got other")
+	}
+
+	return time.Since(start), nil
+}
+
+// GetCache returns the currently configured cache
+func GetCache() StringCache {
+	return defaultCache
+}
+
+// GetString returns the key value from cache with callback when no key exists in cache
+func GetString(key string, getFunc func() (string, error)) (string, error) {
+	if defaultCache == nil || setting.CacheService.TTL == 0 {
+		return getFunc()
+	}
+	cached, exist := defaultCache.Get(key)
+	if !exist {
+		value, err := getFunc()
+		if err != nil {
+			return value, err
+		}
+		return value, defaultCache.Put(key, value, setting.CacheService.TTLSeconds())
+	}
+	return cached, nil
+}
+
+// GetInt64 returns key value from cache with callback when no key exists in cache
+func GetInt64(key string, getFunc func() (int64, error)) (int64, error) {
+	s, err := GetString(key, func() (string, error) {
+		v, err := getFunc()
+		return strconv.FormatInt(v, 10), err
+	})
+	if err != nil {
+		return 0, err
+	}
+	if s == "" {
+		return 0, nil
+	}
+	return strconv.ParseInt(s, 10, 64)
+}
+
+// Remove key from cache
+func Remove(key string) {
+	if defaultCache == nil {
+		return
+	}
+	_ = defaultCache.Delete(key)
+}