我在发JSON请求

req, err := http.NewRequest("GET", myPath, nil)
if err != nil {
  panic(err)
}

resp, err := http.DefaultClient.Do(req)
if err != nil {
  panic(err)
}

defer resp.Body.Close()
var j map[string]interface{}
err = json.NewDecoder(resp.Body).Decode(&j)
if err != nil {
  panic(err)
}

现在返回一个map[string]interface{}
但JSON中数据的实际形状是：

{
  key1: "string"
  key2: "string"
  key3: [
   { key1: "string", key2: "int", key3: "Array<string>" },
   { key1: "string", key2: "int", key3: "Array<string>" },
   ...a lot more
  ] 
}

我如何才能真正获得key3数据？

for key, value := range j {
  if key == "key3" {
    // Im stuck here, 
  }
}

我尝试将JSON响应解组为结构体，并将其解码为该结构体

type key3Struct struct {
  key1 string
  key2 string
  key3 []string
}

type ResponseStruct struct {
  key1 string
  key2 string 
  key3 []key3Struct
}

// Attempt 1
j = ResponseStruct{}
json.NewDecoder(resp.Body).Decode(&j)
==> error cant convert map[string]interface{} to ResponseStruct{}

// Attempt 2
json.Unmarshal(resp.Body, &j)
==> it looks like [ {} ] no data in it...