vue2.0之axios使用詳解(一)

axios

基於 Promise 的 HTTP 請求客戶端，可同時在瀏覽器和 Node.js 中使用http://blog.csdn.NET/binginsist/article/details/65630547

功能特性

• 在瀏覽器中發送 XMLHttpRequests 請求
• 在 node.js 中發送 http請求
• 支持 Promise API
• 攔截請求和響應
• 轉換請求和響應數據
• 自動轉換 JSON 數據
• 客戶端支持保護安全免受 XSRF 攻擊

瀏覽器支持

安裝

使用 bower:

$ bower install axios

使用 npm:

$ npm install axios

例子

發送一個 GET 請求

// Make a request for a user with a given ID
axios.get('/user?ID=12345')
  .then(function (response) {
    console.log(response);
  })
  .catch(function (response) {
    console.log(response);
  });

// Optionally the request above could also be done as
axios.get('/user', {
    params: {
      ID: 12345
    }
  })
  .then(function (response) {
    console.log(response);
  })
  .catch(function (response) {
    console.log(response);
  });

發送一個 POST 請求

axios.post('/user', {
    firstName: 'Fred',
    lastName: 'Flintstone'
  })
  .then(function (response) {
    console.log(response);
  })
  .catch(function (response) {
    console.log(response);
  });

發送多個併發請求

function getUserAccount() {
  return axios.get('/user/12345');
}

function getUserPermissions() {
  return axios.get('/user/12345/permissions');
}

axios.all([getUserAccount(), getUserPermissions()])
  .then(axios.spread(function (acct, perms) {
    // Both requests are now complete
  }));

axios API

可以通過給 axios傳遞對應的參數來定製請求：

axios(config)

// Send a POST request
axios({
  method: 'post',
  url: '/user/12345',
  data: {
    firstName: 'Fred',
    lastName: 'Flintstone'
  }
});

axios(url[, config])

// Sned a GET request (default method)
axios('/user/12345');

請求方法別名

爲方便起見，我們爲所有支持的請求方法都提供了別名

axios.get(url[, config])

axios.delete(url[, config])

axios.head(url[, config])

axios.post(url[, data[, config]])

axios.put(url[, data[, config]])

axios.patch(url[, data[, config]])

注意

當使用別名方法時， url、 method 和 data 屬性不需要在 config 參數裏面指定。

併發

處理併發請求的幫助方法

axios.all(iterable)

axios.spread(callback)

創建一個實例

你可以用自定義配置創建一個新的 axios 實例。

axios.create([config])

var instance = axios.create({
  baseURL: 'https://some-domain.com/api/',
  timeout: 1000,
  headers: {'X-Custom-Header': 'foobar'}
});

實例方法

所有可用的實例方法都列在下面了，指定的配置將會和該實例的配置合併。

axios#request(config)

axios#get(url[, config])

axios#delete(url[, config])

axios#head(url[, config])

axios#post(url[, data[, config]])

axios#put(url[, data[, config]])

axios#patch(url[, data[, config]])

請求配置

下面是可用的請求配置項，只有 url 是必需的。如果沒有指定 method ，默認的請求方法是 GET。

{
  // `url` is the server URL that will be used for the request
  url: '/user',

  // `method` is the request method to be used when making the request
  method: 'get', // default

  // `baseURL` will be prepended to `url` unless `url` is absolute. 
  // It can be convenient to set `baseURL` for an instance of axios to pass relative URLs 
  // to methods of that instance.
  baseURL: 'https://some-domain.com/api/',

  // `transformRequest` allows changes to the request data before it is sent to the server
  // This is only applicable for request methods 'PUT', 'POST', and 'PATCH'
  // The last function in the array must return a string or an ArrayBuffer
  transformRequest: [function (data) {
    // Do whatever you want to transform the data

    return data;
  }],

  // `transformResponse` allows changes to the response data to be made before
  // it is passed to then/catch
  transformResponse: [function (data) {
    // Do whatever you want to transform the data

    return data;
  }],

  // `headers` are custom headers to be sent
  headers: {'X-Requested-With': 'XMLHttpRequest'},

  // `params` are the URL parameters to be sent with the request
  params: {
    ID: 12345
  },

  // `paramsSerializer` is an optional function in charge of serializing `params`
  // (e.g. https://www.npmjs.com/package/qs, http://api.jquery.com/jquery.param/)
  paramsSerializer: function(params) {
    return Qs.stringify(params, {arrayFormat: 'brackets'})
  },

  // `data` is the data to be sent as the request body
  // Only applicable for request methods 'PUT', 'POST', and 'PATCH'
  // When no `transformRequest` is set, must be a string, an ArrayBuffer or a hash
  data: {
    firstName: 'Fred'
  },

  // `timeout` specifies the number of milliseconds before the request times out.
  // If the request takes longer than `timeout`, the request will be aborted.
  timeout: 1000,

  // `withCredentials` indicates whether or not cross-site Access-Control requests
  // should be made using credentials
  withCredentials: false, // default

  // `adapter` allows custom handling of requests which makes testing easier.
  // Call `resolve` or `reject` and supply a valid response (see [response docs](#response-api)).
  adapter: function (resolve, reject, config) {
    /* ... */
  },

  // `auth` indicates that HTTP Basic auth should be used, and supplies credentials.
  // This will set an `Authorization` header, overwriting any existing
  // `Authorization` custom headers you have set using `headers`.
  auth: {
    username: 'janedoe',
    password: 's00pers3cret'
  }

  // `responseType` indicates the type of data that the server will respond with
  // options are 'arraybuffer', 'blob', 'document', 'json', 'text'
  responseType: 'json', // default

  // `xsrfCookieName` is the name of the cookie to use as a value for xsrf token
  xsrfCookieName: 'XSRF-TOKEN', // default

  // `xsrfHeaderName` is the name of the http header that carries the xsrf token value
  xsrfHeaderName: 'X-XSRF-TOKEN', // default

  // `progress` allows handling of progress events for 'POST' and 'PUT uploads'
  // as well as 'GET' downloads
  progress: function(progressEvent) {
    // Do whatever you want with the native progress event
  }
}

響應的數據結構

響應的數據包括下面的信息：

{
  // `data` is the response that was provided by the server
  data: {},

  // `status` is the HTTP status code from the server response
  status: 200,

  // `statusText` is the HTTP status message from the server response
  statusText: 'OK',

  // `headers` the headers that the server responded with
  headers: {},

  // `config` is the config that was provided to `axios` for the request
  config: {}
}

當使用 then 或者 catch 時, 你會收到下面的響應：

axios.get('/user/12345')
  .then(function(response) {
    console.log(response.data);
    console.log(response.status);
    console.log(response.statusText);
    console.log(response.headers);
    console.log(response.config);
});

默認配置

你可以爲每一個請求指定默認配置。

全局 axios 默認配置

axios.defaults.baseURL = 'https://api.example.com';
axios.defaults.headers.common['Authorization'] = AUTH_TOKEN;
axios.defaults.headers.post['Content-Type'] = 'application/x-www-form-urlencoded';

自定義實例默認配置

// Set config defaults when creating the instance
var instance = axios.create({
  baseURL: 'https://api.example.com'
});

// Alter defaults after instance has been created
instance.defaults.headers.common['Authorization'] = AUTH_TOKEN;

配置的優先順序

Config will be merged with an order of precedence. The order is library defaults found in lib/defaults.js, then defaults property of the instance, and finally config argument for the request. The latter will take precedence over the former. Here's an example.

// Create an instance using the config defaults provided by the library
// At this point the timeout config value is `0` as is the default for the library
var instance = axios.create();

// Override timeout default for the library
// Now all requests will wait 2.5 seconds before timing out
instance.defaults.timeout = 2500;

// Override timeout for this request as it's known to take a long time
instance.get('/longRequest', {
  timeout: 5000
}); 

攔截器

你可以在處理 then 或 catch 之前攔截請求和響應

// 添加一個請求攔截器
axios.interceptors.request.use(function (config) {
    // Do something before request is sent
    return config;
  }, function (error) {
    // Do something with request error
    return Promise.reject(error);
  });

// 添加一個響應攔截器
axios.interceptors.response.use(function (response) {
    // Do something with response data
    return response;
  }, function (error) {
    // Do something with response error
    return Promise.reject(error);
  });

移除一個攔截器：

var myInterceptor = axios.interceptors.request.use(function () {/*...*/});
axios.interceptors.request.eject(myInterceptor);

你可以給一個自定義的 axios 實例添加攔截器：

var instance = axios.create();
instance.interceptors.request.use(function () {/*...*/});

錯誤處理

axios.get('/user/12345')
  .catch(function (response) {
    if (response instanceof Error) {
      // Something happened in setting up the request that triggered an Error
      console.log('Error', response.message);
    } else {
      // The request was made, but the server responded with a status code
      // that falls out of the range of 2xx
      console.log(response.data);
      console.log(response.status);
      console.log(response.headers);
      console.log(response.config);
    }
  });

Promises

axios 依賴一個原生的 ES6 Promise 實現，如果你的瀏覽器環境不支持 ES6 Promises，你需要引入 polyfill

TypeScript

axios 包含一個 TypeScript 定義

/// <reference path="axios.d.ts" />
import * as axios from 'axios';
axios.get('/user?ID=12345');