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  • 基于 Promise 的 HTTP 请求客户端 axios

    基于 Promise 的 HTTP 请求客户端,可同时在浏览器和 node.js 中使用

    功能特性

    • 在浏览器中发送 XMLHttpRequests 请求
    • 在 node.js 中发送 http请求
    • 支持 Promise API
    • 拦截请求和响应
    • 转换请求和响应数据
    • 自动转换 JSON 数据
    • 客户端支持保护安全免受 XSRF 攻击

    浏览器支持

    Browser Matrix

    安装

    使用 bower:

    $ bower install axios
    

    使用 npm:

    $ npm install axios
    

    例子

    发送一个 GET 请求

    // 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);
      });
    

    发送一个 POST 请求

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

    发送多个并发请求

    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

    可以通过给 axios传递对应的参数来定制请求:

    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');
    

    请求方法别名

    为方便起见,我们为所有支持的请求方法都提供了别名

    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

    当使用别名方法时, url、 method 和 data 属性不需要在 config 参数里面指定。

    并发

    处理并发请求的帮助方法

    axios.all(iterable)
    axios.spread(callback)

    创建一个实例

    你可以用自定义配置创建一个新的 axios 实例。

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

    实例方法

    所有可用的实例方法都列在下面了,指定的配置将会和该实例的配置合并。

    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]])

    请求配置

    下面是可用的请求配置项,只有 url 是必需的。如果没有指定 method ,默认的请求方法是 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
      }
    }
    

    响应的数据结构

    响应的数据包括下面的信息:

    {
      // `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: {}
    }
    

    当使用 then 或者 catch 时, 你会收到下面的响应:

    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);
    });
    

    默认配置

    你可以为每一个请求指定默认配置。

    全局 axios 默认配置

    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';
    

    自定义实例默认配置

    // 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;
    

    配置的优先顺序

    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
    }); 
    

    拦截器

    你可以在处理 then 或 catch 之前拦截请求和响应

    // 添加一个请求拦截器
    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);
      });
    
    // 添加一个响应拦截器
    axios.interceptors.response.use(function (response) {
        // Do something with response data
        return response;
      }, function (error) {
        // Do something with response error
        return Promise.reject(error);
      });
    

    移除一个拦截器:

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

    你可以给一个自定义的 axios 实例添加拦截器:

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

    错误处理

    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 依赖一个原生的 ES6 Promise 实现,如果你的浏览器环境不支持 ES6 Promises,你需要引入 polyfill

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  • 原文地址:https://www.cnblogs.com/axl234/p/6605025.html
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