您的当前位置：首页正文

axios怎样基于Promise的HTTP请求客户端

2020-11-27 来源：星星旅游

这次给大家带来axios怎样基于Promise的HTTP请求客户端，axios基于Promise的HTTP请求客户端的注意事项有哪些，下面就是实战案例，一起来看一下。

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PromiseAPI

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

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 IDaxios.get('/user?ID=12345').then(function(response){console.log(response);}).catch(function(response){console.log(response);});
// Optionally the request above could also be done asaxios.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

functiongetUserAccount(){returnaxios.get('/user/12345');}functiongetUserPermissions(){returnaxios.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 requestaxios({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])
varinstance=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 requesturl:'/user',
// `method` is the request method to be used when making the requestmethod:'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:' 
// `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 ArrayBuffertransformRequest:[function(data){
// Do whatever you want to transform the datareturndata;}],
// `transformResponse` allows changes to the response data to be made before
// it is passed to then/catchtransformResponse:[function(data){
// Do whatever you want to transform the datareturndata;}],
// `headers` are custom headers to be sentheaders:{'X-Requested-With':'XMLHttpRequest'},
// `params` are the URL parameters to be sent with the requestparams:{ID:12345},
// `paramsSerializer` is an optional function in charge of serializing `params`
// (e.g. https://www.npmjs.com/package/qs, paramsSerializer:function(params){returnQs.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 hashdata:{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 credentialswithCredentials: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 tokenxsrfCookieName:'XSRF-TOKEN',
// default// `xsrfHeaderName` is the name of the http header that carries the xsrf token valuexsrfHeaderName:'X-XSRF-TOKEN',
// default// `progress` allows handling of progress events for 'POST' and 'PUT uploads'
// as well as 'GET' downloadsprogress: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 serverdata:{},
// `status` is the HTTP status code from the server responsestatus:200,
// `statusText` is the HTTP status message from the server responsestatusText:'OK',
// `headers` the headers that the server responded withheaders:{},
// `config` is the config that was provided to `axios` for the requestconfig:{}}

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 instancevarinstance=axios.create({baseURL:' 
// Alter defaults after instance has been createdinstance.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 inlib
/defaults.js, thendefaultsproperty of the instance, and finallyconfigargument 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 libraryvarinstance=axios.create();
// Override timeout default for the library
// Now all requests will wait 2.5 seconds before timing outinstance.defaults.timeout=2500;
// Override timeout for this request as it's known to take a long timeinstance.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 sentreturnconfig;},function(error){
// Do something with request errorreturnPromise.reject(error);});
// 添加一个响应拦截器axios.interceptors.response.use(function(response){
// Do something with response datareturnresponse;},function(error){
// Do something with response errorreturnPromise.reject(error);});

移除一个拦截器：

varmyInterceptor=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：

varinstance=axios.create();instance.interceptors.request.use(function(){/*...*/});
错误处理
axios.get('/user/12345').catch(function(response){if(responseinstanceofError){
// Something happened in setting up the request that triggered an Errorconsole.log('Error',response.message);}else{
// The request was made, but the server responded with a status code
// that falls out of the range of 2xxconsole.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
TypeScript
axios 包含一个TypeScript定义
/// import*asaxiosfrom'axios';axios.get('/user?ID=12345');
Credits
axios is heavily inspired by the$http serviceprovided inAngular. Ultimately axios is an effort to provide a standalone$http-like service for use outside of Angular.
License
MIT

相信看了本文案例你已经掌握了方法，更多精彩请关注Gxl网其它相关文章！