|
| 1 | +package helper |
| 2 | + |
| 3 | +import ( |
| 4 | + "errors" |
| 5 | + "fmt" |
| 6 | + "os" |
| 7 | + "runtime" |
| 8 | + "sync" |
| 9 | + |
| 10 | + "github.com/bytedance/sonic" |
| 11 | + "github.com/hdt3213/rdb/core" |
| 12 | + "github.com/hdt3213/rdb/model" |
| 13 | +) |
| 14 | + |
| 15 | +var jsonEncoder = sonic.ConfigDefault |
| 16 | + |
| 17 | +// ConcurrentOption sets the number of goroutines for json converter |
| 18 | +type ConcurrentOption int |
| 19 | + |
| 20 | +// WithConcurrent sets the number of goroutines for json converter |
| 21 | +func WithConcurrent(c int) ConcurrentOption { |
| 22 | + return ConcurrentOption(c) |
| 23 | +} |
| 24 | + |
| 25 | +// ToJsons read rdb file and convert to json file |
| 26 | +func ToJsons(rdbFilename string, jsonFilename string, options ...interface{}) error { |
| 27 | + if rdbFilename == "" { |
| 28 | + return errors.New("src file path is required") |
| 29 | + } |
| 30 | + if jsonFilename == "" { |
| 31 | + return errors.New("output file path is required") |
| 32 | + } |
| 33 | + // open file |
| 34 | + rdbFile, err := os.Open(rdbFilename) |
| 35 | + if err != nil { |
| 36 | + return fmt.Errorf("open rdb %s failed, %v", rdbFilename, err) |
| 37 | + } |
| 38 | + defer func() { |
| 39 | + _ = rdbFile.Close() |
| 40 | + }() |
| 41 | + jsonFile, err := os.Create(jsonFilename) |
| 42 | + if err != nil { |
| 43 | + return fmt.Errorf("create json %s failed, %v", jsonFilename, err) |
| 44 | + } |
| 45 | + defer func() { |
| 46 | + _ = jsonFile.Close() |
| 47 | + }() |
| 48 | + // create decoder |
| 49 | + var dec decoder = core.NewDecoder(rdbFile) |
| 50 | + if dec, err = wrapDecoder(dec, options...); err != nil { |
| 51 | + return err |
| 52 | + } |
| 53 | + // parse rdb |
| 54 | + _, err = jsonFile.WriteString("[\n") |
| 55 | + if err != nil { |
| 56 | + return fmt.Errorf("write json failed, %v", err) |
| 57 | + } |
| 58 | + |
| 59 | + // parse options |
| 60 | + concurrent := 1 |
| 61 | + cpuNum := runtime.NumCPU() |
| 62 | + if cpuNum > 1 { |
| 63 | + concurrent = cpuNum - 1 // leave one core for parser |
| 64 | + } |
| 65 | + for _, opt := range options { |
| 66 | + switch o := opt.(type) { |
| 67 | + case ConcurrentOption: |
| 68 | + concurrent = int(o) |
| 69 | + } |
| 70 | + } |
| 71 | + |
| 72 | + redisObjectBuffer := make(chan model.RedisObject, 1000) |
| 73 | + jsonStringBuffer := make(chan []byte, 1000) |
| 74 | + |
| 75 | + // parser goroutine |
| 76 | + empty := true |
| 77 | + go func() { |
| 78 | + err = dec.Parse(func(object model.RedisObject) bool { |
| 79 | + redisObjectBuffer <- object |
| 80 | + return true |
| 81 | + }) |
| 82 | + close(redisObjectBuffer) |
| 83 | + }() |
| 84 | + // json marshaller goroutine |
| 85 | + wg := &sync.WaitGroup{} |
| 86 | + wg.Add(concurrent) |
| 87 | + for i := 0; i < concurrent; i++ { |
| 88 | + go func() { |
| 89 | + for object := range redisObjectBuffer { |
| 90 | + data, err := jsonEncoder.Marshal(object) // enable SortMapKeys to ensure same result |
| 91 | + if err != nil { |
| 92 | + fmt.Printf("json marshal failed: %v", err) |
| 93 | + continue |
| 94 | + } |
| 95 | + jsonStringBuffer <- data |
| 96 | + } |
| 97 | + wg.Done() |
| 98 | + }() |
| 99 | + } |
| 100 | + // write goroutine |
| 101 | + wg2 := &sync.WaitGroup{} |
| 102 | + wg2.Add(1) |
| 103 | + go func() { |
| 104 | + for data := range jsonStringBuffer { |
| 105 | + data = append(data, ',', '\n') |
| 106 | + _, err = jsonFile.Write(data) |
| 107 | + if err != nil { |
| 108 | + fmt.Printf("write failed: %v", err) |
| 109 | + continue |
| 110 | + } |
| 111 | + empty = false |
| 112 | + } |
| 113 | + wg2.Done() |
| 114 | + }() |
| 115 | + |
| 116 | + wg.Wait() |
| 117 | + close(jsonStringBuffer) |
| 118 | + wg2.Wait() // wait writing goroutine |
| 119 | + |
| 120 | + // finish json |
| 121 | + if !empty { |
| 122 | + _, err = jsonFile.Seek(-2, 2) |
| 123 | + if err != nil { |
| 124 | + return fmt.Errorf("error during seek in file: %v", err) |
| 125 | + } |
| 126 | + } |
| 127 | + _, err = jsonFile.WriteString("\n]") |
| 128 | + if err != nil { |
| 129 | + return fmt.Errorf("error during write in file: %v", err) |
| 130 | + } |
| 131 | + return nil |
| 132 | +} |
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