Sub2API v1.0 - AI API 网关（二开初始版本，基于上游 Wei-Shaw/sub2api）

backend/internal/repository/leader_lock_cache.go

@@ -0,0 +1,42 @@
+package repository
+
+import (
+	"context"
+	"time"
+
+	"github.com/Wei-Shaw/sub2api/internal/service"
+
+	"github.com/redis/go-redis/v9"
+)
+
+const leaderLockKeyPrefix = "leader:lock:"
+
+// leaderLockReleaseScript releases a leader lock only when the caller still owns
+// it (compare-and-delete by owner token). This prevents a previous holder whose
+// lock already expired — and was re-acquired by another instance — from deleting
+// the new owner's lock.
+var leaderLockReleaseScript = redis.NewScript(`
+if redis.call("GET", KEYS[1]) == ARGV[1] then
+  return redis.call("DEL", KEYS[1])
+end
+return 0
+`)
+
+type leaderLockCache struct {
+	rdb *redis.Client
+}
+
+// NewLeaderLockCache returns a Redis-backed implementation of
+// service.LeaderLockCache used by periodic background jobs to elect a single
+// runner across instances.
+func NewLeaderLockCache(rdb *redis.Client) service.LeaderLockCache {
+	return &leaderLockCache{rdb: rdb}
+}
+
+func (c *leaderLockCache) TryAcquireLeaderLock(ctx context.Context, key, owner string, ttl time.Duration) (bool, error) {
+	return c.rdb.SetNX(ctx, leaderLockKeyPrefix+key, owner, ttl).Result()
+}
+
+func (c *leaderLockCache) ReleaseLeaderLock(ctx context.Context, key, owner string) error {
+	return leaderLockReleaseScript.Run(ctx, c.rdb, []string{leaderLockKeyPrefix + key}, owner).Err()
+}