快递机构要求与型号不符，但仍可以使用吗？

Question

我的班级模型：

class User {
   userName: string;
   password: string;
}

我的函数句柄：

const users = [];
function addUser(user: User) {
  users.push(user);
}

快速路由器：

router.post('/users', (req, res) => {
  addUser(req.body);
})

我想请求以下userModel格式。 但是，当我请求一个不遵循userModel格式的对象时，addUser函数仍然起作用，并将错误的对象格式推送给users []。

如果req.body与userModel不匹配，如何抛出错误

Answer 1

我能够使用type-safe-json-decoder来实现所需的行为：

index.js

import express = require("express");
import bodyParser from "body-parser";
import { Decoder, object, string } from 'type-safe-json-decoder'

const app: express.Application = express();
app.use(bodyParser.json());

class User {
    constructor(userName: string, password: string) {
        this.userName = userName;
        this.password = password
    }
    userName: string;
    password: string;
}

const usersDecoder: Decoder<User> = object(
    ['userName', string()],
    ['password', string()],
    (userName, password) => ({ userName, password })
);

const users: User[] = [];
function addUser(user: User) {
    users.push(user);
    console.log(users);
}

app.post('/add', (req, res) => {
    const user: User = usersDecoder.decodeJSON(JSON.stringify(req.body))
    addUser(user);
    res.send("User added!");
});

app.listen(8080, () => console.log("Listening on 8080"));

package.json

{
  "name": "ts",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "tsc": "tsc"
  },
  "author": "",
  "license": "ISC",
  "dependencies": {
    "@types/express": "^4.16.1",
    "body-parser": "^1.18.3",
    "express": "^4.16.4",
    "type-safe-json-decoder": "^0.2.0",
    "typescript": "^3.4.1"
  },
  "devDependencies": {
    "@types/body-parser": "^1.17.0"
  }
}

要运行：

1. npm install
2. npm run tsc -- --init
3. npm run tsc
4. node index.js

使用正确的JSON执行POST时，您应该收到：User added!。

如果JSON格式不正确，则会引发错误：