1 files changed, 184 insertions, 0 deletions
diff --git a/modules/cache/cache.go b/modules/cache/cache.go
new file mode 100644
index 00000000..546c54df
--- /dev/null
+++ b/modules/cache/cache.go
@@ -0,0 +1,184 @@
+// Copyright 2017 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package cache
+
+import (
+	"fmt"
+	"strconv"
+	"time"
+
+	"code.gitea.io/gitea/modules/setting"
+
+	mc "gitea.com/go-chi/cache"
+
+	_ "gitea.com/go-chi/cache/memcache" // memcache plugin for cache
+)
+
+var conn mc.Cache
+
+func newCache(cacheConfig setting.Cache) (mc.Cache, error) {
+	return mc.NewCacher(mc.Options{
+		Adapter:       cacheConfig.Adapter,
+		AdapterConfig: cacheConfig.Conn,
+		Interval:      cacheConfig.Interval,
+	})
+}
+
+// Init start cache service
+func Init() error {
+	var err error
+
+	if conn == nil {
+		if conn, err = newCache(setting.CacheService.Cache); err != nil {
+			return err
+		}
+		if err = conn.Ping(); err != nil {
+			return err
+		}
+	}
+
+	return err
+}
+
+const (
+	testCacheKey       = "DefaultCache.TestKey"
+	SlowCacheThreshold = 100 * time.Microsecond
+)
+
+func Test() (time.Duration, error) {
+	if conn == nil {
+		return 0, fmt.Errorf("default cache not initialized")
+	}
+
+	testData := fmt.Sprintf("%x", make([]byte, 500))
+
+	start := time.Now()
+
+	if err := conn.Delete(testCacheKey); err != nil {
+		return 0, fmt.Errorf("expect cache to delete data based on key if exist but got: %w", err)
+	}
+	if err := conn.Put(testCacheKey, testData, 10); err != nil {
+		return 0, fmt.Errorf("expect cache to store data but got: %w", err)
+	}
+	testVal := conn.Get(testCacheKey)
+	if testVal == nil {
+		return 0, fmt.Errorf("expect cache hit but got none")
+	}
+	if testVal != testData {
+		return 0, fmt.Errorf("expect cache to return same value as stored but got other")
+	}
+
+	return time.Since(start), nil
+}
+
+// GetCache returns the currently configured cache
+func GetCache() mc.Cache {
+	return conn
+}
+
+// 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 conn == nil || setting.CacheService.TTL == 0 {
+		return getFunc()
+	}
+
+	cached := conn.Get(key)
+
+	if cached == nil {
+		value, err := getFunc()
+		if err != nil {
+			return value, err
+		}
+		return value, conn.Put(key, value, setting.CacheService.TTLSeconds())
+	}
+
+	if value, ok := cached.(string); ok {
+		return value, nil
+	}
+
+	if stringer, ok := cached.(fmt.Stringer); ok {
+		return stringer.String(), nil
+	}
+
+	return fmt.Sprintf("%s", cached), nil
+}
+
+// GetInt returns key value from cache with callback when no key exists in cache
+func GetInt(key string, getFunc func() (int, error)) (int, error) {
+	if conn == nil || setting.CacheService.TTL == 0 {
+		return getFunc()
+	}
+
+	cached := conn.Get(key)
+
+	if cached == nil {
+		value, err := getFunc()
+		if err != nil {
+			return value, err
+		}
+
+		return value, conn.Put(key, value, setting.CacheService.TTLSeconds())
+	}
+
+	switch v := cached.(type) {
+	case int:
+		return v, nil
+	case string:
+		value, err := strconv.Atoi(v)
+		if err != nil {
+			return 0, err
+		}
+		return value, nil
+	default:
+		value, err := getFunc()
+		if err != nil {
+			return value, err
+		}
+		return value, conn.Put(key, value, setting.CacheService.TTLSeconds())
+	}
+}
+
+// GetInt64 returns key value from cache with callback when no key exists in cache
+func GetInt64(key string, getFunc func() (int64, error)) (int64, error) {
+	if conn == nil || setting.CacheService.TTL == 0 {
+		return getFunc()
+	}
+
+	cached := conn.Get(key)
+
+	if cached == nil {
+		value, err := getFunc()
+		if err != nil {
+			return value, err
+		}
+
+		return value, conn.Put(key, value, setting.CacheService.TTLSeconds())
+	}
+
+	switch v := conn.Get(key).(type) {
+	case int64:
+		return v, nil
+	case string:
+		value, err := strconv.ParseInt(v, 10, 64)
+		if err != nil {
+			return 0, err
+		}
+		return value, nil
+	default:
+		value, err := getFunc()
+		if err != nil {
+			return value, err
+		}
+
+		return value, conn.Put(key, value, setting.CacheService.TTLSeconds())
+	}
+}
+
+// Remove key from cache
+func Remove(key string) {
+	if conn == nil {
+		return
+	}
+	_ = conn.Delete(key)
+}