Question

我似乎有异步问题。我在整个应用程序中使用react，express，sequelize和mariadb。我在前端使用axios发出get请求。但是，get请求始终返回一个空值。但是，在我的后端代码中，我知道请求正在调用数据库findAll（）。

前端（反应/ Axios）

componentDidMount() {
   this.getPets();
}

 getPets = async () => {
    try {
        const resp = await axios.get('/getdogs');
        this.setState({ pets: resp.body });
        console.log(resp.data);
    } catch (err) {
        // Handle Error Here
        console.error(err);
    }

server.js

app.get('/getdogs', (req, res) => {
  console.log("IN THE FUNCTION");
  const pets = db.getPets();
  console.log("All pets:", JSON.stringify(pets, null, 2));

  res.send(pets);
});

database.js

async function getPets() {
  const pets = await Pets.findAll();
  console.log("All pets:", JSON.stringify(pets, null, 2));
  return JSON.stringify(pets, null, 2);
}

server.js的输出

nodemon] starting `node server.js`
Listening on port 5000
IN THE FUNCTION
All pets: {}
warning: please use IANA standard timezone format ('Etc/GMT0')
warning: please use IANA standard timezone format ('Etc/GMT0')
Executing (default): SELECT `id`, `name`, `createdAt`, `updatedAt` FROM `Pets` AS `Pets`;
All pets: [
  {
    "id": 1,
    "name": "HULK",
    "createdAt": "2020-09-15T23:09:43.000Z",
    "updatedAt": "2020-09-15T23:09:43.000Z"
  },
  {
    "id": 2,
    "name": "Martha",
    "createdAt": "2020-09-15T23:09:43.000Z",
    "updatedAt": "2020-09-15T23:09:43.000Z"
  },
  {
    "id": 3,
    "name": "Bernie",
    "createdAt": "2020-09-15T23:09:43.000Z",
    "updatedAt": "2020-09-15T23:09:43.000Z"
  }
]

Answer 1

axios响应不具有body属性。响应位于data属性中，请参见Response schema

 this.setState({ pets: resp.data });
        console.log(resp.data);

您还没有等待DB的结果：

db.getPets().then(pets => {
  console.log("All pets:", JSON.stringify(pets, null, 2));

  res.send(pets);
});

Axios Get请求出现问题-可能是异步问题

1 个答案: