Cache last commit to accelerate the repository directory page visit (#10069)

* Cache last commit to accelerate the repository directory page visit

* Default use default cache configuration

* add tests for last commit cache

* Simplify last commit cache

* Revert Enabled back

* Change the last commit cache default ttl to 8760h

* Fix test

1 files changed, 17 insertions, 9 deletions

diff --git a/modules/cache/cache.go b/modules/cache/cache.go
index 20d23f3b5b..e3a905e3fa 100644
--- a/modules/cache/cache.go
+++ b/modules/cache/cache.go
@@ -16,20 +16,28 @@ import (
 	_ "gitea.com/macaron/cache/redis"
 )
 
-var conn mc.Cache
+var (
+	conn mc.Cache
+)
+
+func newCache(cacheConfig setting.Cache) (mc.Cache, error) {
+	return mc.NewCacher(cacheConfig.Adapter, mc.Options{
+		Adapter:       cacheConfig.Adapter,
+		AdapterConfig: cacheConfig.Conn,
+		Interval:      cacheConfig.Interval,
+	})
+}
 
 // NewContext start cache service
 func NewContext() error {
-	if setting.CacheService == nil || conn != nil {
-		return nil
+	var err error
+
+	if conn == nil && setting.CacheService.Enabled {
+		if conn, err = newCache(setting.CacheService.Cache); err != nil {
+			return err
+		}
 	}
 
-	var err error
-	conn, err = mc.NewCacher(setting.CacheService.Adapter, mc.Options{
-		Adapter:       setting.CacheService.Adapter,
-		AdapterConfig: setting.CacheService.Conn,
-		Interval:      setting.CacheService.Interval,
-	})
 	return err
 }