1 files changed, 92 insertions, 0 deletions
diff --git a/modules/queue/base_levelqueue_common.go b/modules/queue/base_levelqueue_common.go
new file mode 100644
index 0000000000..409a965517
--- /dev/null
+++ b/modules/queue/base_levelqueue_common.go
@@ -0,0 +1,92 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package queue
+
+import (
+	"context"
+	"fmt"
+	"path/filepath"
+	"strings"
+	"sync"
+	"time"
+
+	"code.gitea.io/gitea/modules/nosql"
+
+	"gitea.com/lunny/levelqueue"
+	"github.com/syndtr/goleveldb/leveldb"
+)
+
+type baseLevelQueuePushPoper interface {
+	RPush(data []byte) error
+	LPop() ([]byte, error)
+	Len() int64
+}
+
+type baseLevelQueueCommonImpl struct {
+	length   int
+	internal baseLevelQueuePushPoper
+	mu       *sync.Mutex
+}
+
+func (q *baseLevelQueueCommonImpl) PushItem(ctx context.Context, data []byte) error {
+	return backoffErr(ctx, backoffBegin, backoffUpper, time.After(pushBlockTime), func() (retry bool, err error) {
+		if q.mu != nil {
+			q.mu.Lock()
+			defer q.mu.Unlock()
+		}
+
+		cnt := int(q.internal.Len())
+		if cnt >= q.length {
+			return true, nil
+		}
+		retry, err = false, q.internal.RPush(data)
+		if err == levelqueue.ErrAlreadyInQueue {
+			err = ErrAlreadyInQueue
+		}
+		return retry, err
+	})
+}
+
+func (q *baseLevelQueueCommonImpl) PopItem(ctx context.Context) ([]byte, error) {
+	return backoffRetErr(ctx, backoffBegin, backoffUpper, infiniteTimerC, func() (retry bool, data []byte, err error) {
+		if q.mu != nil {
+			q.mu.Lock()
+			defer q.mu.Unlock()
+		}
+
+		data, err = q.internal.LPop()
+		if err == levelqueue.ErrNotFound {
+			return true, nil, nil
+		}
+		if err != nil {
+			return false, nil, err
+		}
+		return false, data, nil
+	})
+}
+
+func baseLevelQueueCommon(cfg *BaseConfig, internal baseLevelQueuePushPoper, mu *sync.Mutex) *baseLevelQueueCommonImpl {
+	return &baseLevelQueueCommonImpl{length: cfg.Length, internal: internal}
+}
+
+func prepareLevelDB(cfg *BaseConfig) (conn string, db *leveldb.DB, err error) {
+	if cfg.ConnStr == "" { // use data dir as conn str
+		if !filepath.IsAbs(cfg.DataFullDir) {
+			return "", nil, fmt.Errorf("invalid leveldb data dir (not absolute): %q", cfg.DataFullDir)
+		}
+		conn = cfg.DataFullDir
+	} else {
+		if !strings.HasPrefix(cfg.ConnStr, "leveldb://") {
+			return "", nil, fmt.Errorf("invalid leveldb connection string: %q", cfg.ConnStr)
+		}
+		conn = cfg.ConnStr
+	}
+	for i := 0; i < 10; i++ {
+		if db, err = nosql.GetManager().GetLevelDB(conn); err == nil {
+			break
+		}
+		time.Sleep(1 * time.Second)
+	}
+	return conn, db, err
+}