ExamplePrefixQueue demonstrates the implementation of a Goque queue.
()
| 8 | |
| 9 | // ExamplePrefixQueue demonstrates the implementation of a Goque queue. |
| 10 | func Example_prefixQueue() { |
| 11 | // Open/create a prefix queue. |
| 12 | pq, err := goque.OpenPrefixQueue("data_dir") |
| 13 | if err != nil { |
| 14 | fmt.Println(err) |
| 15 | return |
| 16 | } |
| 17 | defer pq.Close() |
| 18 | |
| 19 | // Enqueue an item. |
| 20 | item, err := pq.Enqueue([]byte("prefix"), []byte("item value")) |
| 21 | if err != nil { |
| 22 | fmt.Println(err) |
| 23 | return |
| 24 | } |
| 25 | |
| 26 | fmt.Println(item.ID) // 1 |
| 27 | fmt.Println(item.Key) // [112 114 101 102 105 120 0 0 0 0 0 0 0 0 1] |
| 28 | fmt.Println(item.Value) // [105 116 101 109 32 118 97 108 117 101] |
| 29 | fmt.Println(item.ToString()) // item value |
| 30 | |
| 31 | // Change the item value in the queue. |
| 32 | item, err = pq.Update([]byte("prefix"), item.ID, []byte("new item value")) |
| 33 | if err != nil { |
| 34 | fmt.Println(err) |
| 35 | return |
| 36 | } |
| 37 | |
| 38 | fmt.Println(item.ToString()) // new item value |
| 39 | |
| 40 | // Dequeue the next item. |
| 41 | deqItem, err := pq.Dequeue([]byte("prefix")) |
| 42 | if err != nil { |
| 43 | fmt.Println(err) |
| 44 | return |
| 45 | } |
| 46 | |
| 47 | fmt.Println(deqItem.ToString()) // new item value |
| 48 | |
| 49 | // Delete the queue and its database. |
| 50 | pq.Drop() |
| 51 | } |