如何使用goreq将json转换为struct？

Question

Using Go I'm trying to get some json from a server for which I'm using the goreq library. When I print out the resulting string as follows:

s, _ := res.Body.ToString()
fmt.Println(s)

I get a correct json string:

{"success":true,"testnet":false,"message":"","result":{"btc":4014.16,"edp":4014.16},"msIn":1505820331492,"msOut":1505820331492}

So using this json-to-go webservice I converted this json message to a struct:

type Index struct {
    Success bool   `json:"success"`
    Testnet bool   `json:"testnet"`
    Message string `json:"message"`
    Result  struct {
        Btc float64 `json:"btc"`
        Edp float64 `json:"edp"`
    } `json:"result"`
    MsIn  int64 `json:"msIn"`
    MsOut int64 `json:"msOut"`
}

and I use that as follows (implementation of FromJsonTo() here):

var item Index
res.Body.FromJsonTo(&item)
fmt.Println(item)

This just prints out the nulled Index struct though (while the json str is still the same):

{false false  {0 0} 0 0}

Any idea what I might be doing wrong here?

Answer 1

By calling res.Body.ToString() you read the whole body of the response. Next, when you call res.Body.FromJsonTo(), body is empty and therefore EOF error is returned. Removing ToString() from your code should help.