我无法json在通过KrakenAPI 接收的Golang结构中强制转换以下内容:
json
Kraken
{ "error": [], "result": { "LINKUSD": { "asks": [ ["2.049720", "183.556", 1576323009], ["2.049750", "555.125", 1576323009], ["2.049760", "393.580", 1576323008], ["2.049980", "206.514", 1576322995] ], "bids": [ ["2.043800", "20.691", 1576322350], ["2.039080", "755.396", 1576323007], ["2.036960", "214.621", 1576323006], ["2.036930", "700.792", 1576322987] ] } } }
使用json-to-go,他给我以下结构:
json-to-go
type AutoGenerated struct { Error []interface{} `json:"error"` Result struct { LINKUSD struct { Asks [][]interface{} `json:"asks"` Bids [][]interface{} `json:"bids"` } `json:"LINKUSD"` } `json:"result"` }
显然,我无法LINKUSD对每种货币对都会改变的原因进行硬编码。
LINKUSD
我已经创建了两个结构来完成任务,但是无法将结果强制转换为结构。
type BitfinexOrderBook struct { Pair string `json:"pair"` Asks []BitfinexOrder `json:"asks"` Bids []BitfinexOrder `json:"bids"` } type BitfinexOrder struct { Price string Volume string Timestamp time.Time }
我的第一个尝试是使用反射。阅读上面发布的JSON数据,我能够检索包含asks和bids列表的接口。
asks
bids
// Just used as a divisor const div string = " ---------------------------------" func test(data []byte) error { var err error // Creating the maps for the JSON data m := map[string]interface{}{} // Parsing/Unmarshalling the json readed from the file err = json.Unmarshal(data, &m) if err != nil { log.Println("Error unmarshalling data: " + err.Error()) return err } // Extract the "result" only a := reflect.ValueOf(m["result"]) if a.Kind() == reflect.Map { key := a.MapKeys()[0] // Extract the key -> LINKUSD log.Println("KEY: ", key, div) strct := a.MapIndex(key) // Extract the value -> asks and bids array log.Println("MAP: ", strct, div) m, _ := strct.Interface().(map[string]interface{}) log.Println("Asks: ", m["asks"], div) // This will print [[value, value, value] ...] related to asks log.Println("Bids: ", m["bids"], div) // This will print [[value, value, value] ...] related to bids // Parse the interface into a []byte asks_data, err := json.Marshal(m["asks"]) log.Println("OK: ", err, div) log.Println("ASKS: ", string(asks_data), div) // Tried without array to (datastructure.BitfinexOrder) var asks []datastructure.BitfinexOrder err = json.Unmarshal(asks_data, &asks) log.Println("ERROR: ", err, div) log.Println("UNMARSHAL: ", asks, div) } return errors.New("UNABLE_PARSE_VALUE") }
下面的两个打印m, _ := strct.Interface().(map[string]interface{})将显示以下interface类型的事实,由于类型的事实,我无法投射以下类似的数据:
m, _ := strct.Interface().(map[string]interface{})
interface
[[2.049720 183.556 1.576323009e+09] [2.049750 555.125 1.576323009e+09] [2.049760 393.580 1.576323008e+09] [2.049980 206.514 1.576322995e+09]]
但是我无法解组数据。
所以我尝试了由提供的其他功能@chmike:
@chmike
// UnmarshalJSON decode a BifinexOrder. func UnmarshalJSON(data []byte) (datastructure.BitfinexOrder, error) { var packedData []json.Number var order datastructure.BitfinexOrder err := json.Unmarshal(data, &packedData) if err != nil { return order, err } order.Price = packedData[0].String() order.Volume = packedData[1].String() t, err := packedData[2].Int64() if err != nil { return order, err } order.Timestamp = time.Unix(t, 0) return order, nil }
但是我收到以下错误:
json: cannot unmarshal array into Go value of type json.Number
一些技巧?
注意 : 我以前的问题已作为“解组切片中2个不同结构”的副本而关闭。 但是,如果您阅读了这些问题,那么我就不会处理两种不同的结构…我正在处理的json包含一个我以前不知道的键。我也无法封送BitfinexOrder
从@mkopriva和@chmike找到解决方案:
感谢你们!
package main import ( "fmt" "time" "encoding/json" ) var data = []byte(`{ "error": [], "result": { "LINKUSD": { "asks": [ ["2.049720", "183.556", 1576323009], ["2.049750", "555.125", 1576323009], ["2.049760", "393.580", 1576323008], ["2.049980", "206.514", 1576322995] ], "bids": [ ["2.043800", "20.691", 1576322350], ["2.039080", "755.396", 1576323007], ["2.036960", "214.621", 1576323006], ["2.036930", "700.792", 1576322987] ] } } }`) type Response struct { Error []interface{} `json:"error"` Result map[string]Order `json:"result"` } type Order struct { Asks []BitfinexOrder `json:"asks"` Bids []BitfinexOrder `json:"bids"` } type BitfinexOrder struct { Price string Volume string Timestamp time.Time } // UnmarshalJSON decode a BifinexOrder. func (b *BitfinexOrder) UnmarshalJSON(data []byte) error { var packedData []json.Number err := json.Unmarshal(data, &packedData) if err != nil { return err } b.Price = packedData[0].String() b.Volume = packedData[1].String() t, err := packedData[2].Int64() if err != nil { return err } b.Timestamp = time.Unix(t, 0) return nil } func main() { res := &Response{} if err := json.Unmarshal(data, res); err != nil { panic(err) } for key, value := range res.Result { fmt.Println(key) for i, ask := range value.Asks { fmt.Printf("Asks[%d] = %#v\n", i, ask) } for i, bid := range value.Bids { fmt.Printf("Bids[%d] = %#v\n", i, bid) } } }