Allow common redis and leveldb connections (#12385)

* Allow common redis and leveldb connections

Prevents multiple reopening of redis and leveldb connections to the same
place by sharing connections.

Further allows for more configurable redis connection type using the
redisURI and a leveldbURI scheme.

Signed-off-by: Andrew Thornton <art27@cantab.net>

* add unit-test

Signed-off-by: Andrew Thornton <art27@cantab.net>

* as per @lunny

Signed-off-by: Andrew Thornton <art27@cantab.net>

* add test

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Update modules/cache/cache_redis.go

* Update modules/queue/queue_disk.go

* Update modules/cache/cache_redis.go

* Update modules/cache/cache_redis.go

* Update modules/queue/unique_queue_disk.go

* Update modules/queue/queue_disk.go

* Update modules/queue/unique_queue_disk.go

* Update modules/session/redis.go

Co-authored-by: techknowlogick <techknowlogick@gitea.io>
Co-authored-by: Lauris BH <lauris@nix.lv>

modules/queue/unique_queue_disk.go

@@ -5,6 +5,8 @@
 package queue
 
 import (
+	"code.gitea.io/gitea/modules/nosql"
+
 	"gitea.com/lunny/levelqueue"
 )
 
@@ -14,7 +16,9 @@ const LevelUniqueQueueType Type = "unique-level"
 // LevelUniqueQueueConfiguration is the configuration for a LevelUniqueQueue
 type LevelUniqueQueueConfiguration struct {
 	ByteFIFOQueueConfiguration
-	DataDir string
+	DataDir          string
+	ConnectionString string
+	QueueName        string
 }
 
 // LevelUniqueQueue implements a disk library queue
@@ -34,7 +38,11 @@ func NewLevelUniqueQueue(handle HandlerFunc, cfg, exemplar interface{}) (Queue,
 	}
 	config := configInterface.(LevelUniqueQueueConfiguration)
 
-	byteFIFO, err := NewLevelUniqueQueueByteFIFO(config.DataDir)
+	if len(config.ConnectionString) == 0 {
+		config.ConnectionString = config.DataDir
+	}
+
+	byteFIFO, err := NewLevelUniqueQueueByteFIFO(config.ConnectionString, config.QueueName)
 	if err != nil {
 		return nil, err
 	}
@@ -55,18 +63,25 @@ var _ (UniqueByteFIFO) = &LevelUniqueQueueByteFIFO{}
 
 // LevelUniqueQueueByteFIFO represents a ByteFIFO formed from a LevelUniqueQueue
 type LevelUniqueQueueByteFIFO struct {
-	internal *levelqueue.UniqueQueue
+	internal   *levelqueue.UniqueQueue
+	connection string
 }
 
 // NewLevelUniqueQueueByteFIFO creates a new ByteFIFO formed from a LevelUniqueQueue
-func NewLevelUniqueQueueByteFIFO(dataDir string) (*LevelUniqueQueueByteFIFO, error) {
-	internal, err := levelqueue.OpenUnique(dataDir)
+func NewLevelUniqueQueueByteFIFO(connection, prefix string) (*LevelUniqueQueueByteFIFO, error) {
+	db, err := nosql.GetManager().GetLevelDB(connection)
+	if err != nil {
+		return nil, err
+	}
+
+	internal, err := levelqueue.NewUniqueQueue(db, []byte(prefix), []byte(prefix+"-unique"), false)
 	if err != nil {
 		return nil, err
 	}
 
 	return &LevelUniqueQueueByteFIFO{
-		internal: internal,
+		connection: connection,
+		internal:   internal,
 	}, nil
 }
 
@@ -96,7 +111,9 @@ func (fifo *LevelUniqueQueueByteFIFO) Has(data []byte) (bool, error) {
 
 // Close this fifo
 func (fifo *LevelUniqueQueueByteFIFO) Close() error {
-	return fifo.internal.Close()
+	err := fifo.internal.Close()
+	_ = nosql.GetManager().CloseLevelDB(fifo.connection)
+	return err
 }
 
 func init() {