| 90 | } |
| 91 | |
| 92 | func ExampleLock_Refresh_watchdog() { |
| 93 | client := redis.NewClient(&redis.Options{Network: "tcp", Addr: "127.0.0.1:6379"}) |
| 94 | defer client.Close() |
| 95 | |
| 96 | locker := redislock.New(client) |
| 97 | |
| 98 | ctx := context.Background() |
| 99 | |
| 100 | // Obtain a lock with a 30s TTL. |
| 101 | const ttl = 30 * time.Second |
| 102 | lock, err := locker.Obtain(ctx, "my-key", ttl, nil) |
| 103 | if err != nil { |
| 104 | log.Fatalln(err) |
| 105 | } |
| 106 | defer lock.Release(context.Background()) |
| 107 | |
| 108 | // Start a watchdog that refreshes the lock every ttl/3. The work context |
| 109 | // is cancelled if a refresh fails so the protected work can abort. |
| 110 | workCtx, cancel := context.WithCancel(ctx) |
| 111 | defer cancel() |
| 112 | |
| 113 | go func() { |
| 114 | t := time.NewTicker(ttl / 3) |
| 115 | defer t.Stop() |
| 116 | for { |
| 117 | select { |
| 118 | case <-workCtx.Done(): |
| 119 | return |
| 120 | case <-t.C: |
| 121 | if err := lock.Refresh(workCtx, ttl, nil); err != nil { |
| 122 | log.Printf("lock refresh failed: %v", err) |
| 123 | cancel() |
| 124 | return |
| 125 | } |
| 126 | } |
| 127 | } |
| 128 | }() |
| 129 | |
| 130 | // ... do work using workCtx ... |
| 131 | fmt.Println("I have a lock!") |
| 132 | } |
| 133 | |
| 134 | func ExampleClient_Obtain_customDeadline() { |
| 135 | client := redis.NewClient(&redis.Options{Network: "tcp", Addr: "127.0.0.1:6379"}) |