求助：解析POST请求中的req.body

Question

我正在使用fetch API 将两个值发送到我的 POST 请求处理程序：

fetch('http://localhost:8080/validation', {
        method:'POST',
        headers: {
            'Accept': 'application/json',
            'Content-Type': 'application/json'
        },
        body: JSON.stringify({
            email:this.state.email,
            password:this.state.password
        })

我想在服务器端保存电子邮件和密码为字符串，以下是我的尝试：

type credentials struct {
    Test string
}

func Validate(rw http.ResponseWriter, req *http.Request, _ httprouter.Params) {

    decoder := json.NewDecoder(req.Body)

    var creds credentials

    err := decoder.Decode(&creds)

    if err != nil {
        panic(err)
    }

    fmt.Println(creds.Test)
}

问题是我不知道发送到 POST 结构的确切格式。我正在尝试将 req.Body 保存为字符串，但是没有得到任何结果。

当输入 fmt.Println 只得到一个空格，解析它的正确方法是什么？

Answer 1

Try with

type credentials struct {
    Email string `json:"email"`
    Password string `json:"password"`
}

You are receiving a JSON with two values. Receiving struct should have a structure matching your request. Otherwise, there are no placeholders to decode the JSON into, as in your case - email and password do not have matching struct fields. Btw. if you send "Test" in your JSON, this would work, as you have a Test field in your struct!

Regarding field names. If fields in JSON do not start with a capital letter or even have different names, then you should use so called tags. More on tags: https://golang.org/pkg/encoding/json/#Marshal

In my example I used them to match struct field names to your json fields, i.e. to make email from json match Email field of the credentials struct.