基于 TS 实现 axios（八）
这一章主要完善接口
目录结构没有进行修改
withCredentials
这个功能是可以携带跨越请求的，默认情况下是自动携带同源 cookie 的 ，但是跨域的时候是不可以进行携带的，将 withCredentials 设置成 true 就可以进行携带了。
types/index.ts
export interface AxiosRequestConfig {
// ...
withCredentials?:boolean,
//...
}
core/xhr.ts
// ...
if(timeout) request.timeout = timeout;
if(withCredentials) {
request.withCredentials = withCredentials;
}
// ...
接改变这点就够了
XSRF
其实就是在 header 中添加 token （后端生成返回的标识）
types/index.ts
export interface AxiosRequestConfig {
// ...
xsrfCookieName?:string,
xsrfHeaderName?:string,
// ...
}
defaults.ts
const defaults: AxiosRequestConfig = {
// ...
xsrfCookieName: 'XSRF-TOKEN',
xsrfHeaderName: 'X-XSRF-TOKEN',
// ...
}
helpers/url.ts
interface URLOrigin{
protocol:string,
host: string,
}
export function isURLsameOrigin(requestURL: string):boolean {
const parseOrigin = resolverURL(requestURL);
return (parseOrigin.protocol === currentOrigin.protocol && parseOrigin.host === currentOrigin.host)
}
const urlParsingNode = document.createElement('a');
const currentOrigin = resolverURL(window.location.href);
function resolverURL(url: string): URLOrigin {
urlParsingNode.setAttribute('href',url);
const {protocol,host} = urlParsingNode;
return {
protocol,
host,
}
}
通过 a 标签拿到 protocol （协议）和 host （主机地址）
新建 helpers/cookie.ts
const cookie = {
read(name: string) : string | null {
const match = document.cookie.match(new RegExp('(^|;\\s*)(' + name + ')=([^;]*)'));
return match ? decodeURIComponent(match[3]) : null;
}
}
export default cookie;
读取 cookie
core/xhr.ts
// ...
request.ontimeout = function handleTimeout() {
reject(createError(`Timeout of ${timeout} ms exceeded`,config,'ECONNABORTED',request));
}
// 添加的部分
if((withCredentials || isURLsameOrigin(url)) && xsrfCookieName){
const xsrfValue = cookie.read(xsrfCookieName);
if(xsrfValue && xsrfHeaderName) {
headers[xsrfHeaderName] = xsrfValue;
}
};
// 添加的部分
// ...
自动设置 cokie ，个人感觉没什么用
下载 和 上传监控
types/index.ts
// ...
export interface AxiosRequestConfig {
// ...
onDownloadProgress?:(e: ProgressEvent) => void,
onUploadProgress?: (e: ProgressEvent) => void,
// ...
}
// ...
helpers/util.ts
export function isFormData(val: any): val is FormData {
return typeof val !== 'undefined' && val instanceof FormData
}
判断对象是否是 FormData
core/xhr.ts
// ... 锚点
request.ontimeout = function handleTimeout() {
reject(createError(`Timeout of ${timeout} ms exceeded`,config,'ECONNABORTED',request));
}
// 添加的部分
if(onDownloadProgress) {
request.onprogress = onDownloadProgress;
}
if(onUploadProgress) {
request.upload.onprogress = onUploadProgress;
}
if(isFormData(data)) {
delete headers['Content-Type']
}
// 添加的部分
// ...
将 上传 和 下载的函数挂载到 request 上；如果 data 是 Formdata 类型的数据就将 Content-Type 删除，浏览器会默认添加的
整理核心库 xhr
import {AxiosRequestConfig,AxiosPromise,AxiosResponse} from '../types';
import {parseHeaders} from '../helpers/header';
import {createError} from '../helpers/error';
import {isURLsameOrigin} from '../helpers/url';
import {isFormData} from '../helpers/util'
import cookie from '../helpers/cookie';
export default function xhr(config:AxiosRequestConfig) : AxiosPromise {
return new Promise((reslove,reject)=> {
const {
data = null,
url,
method='get',
timeout,
headers,
responseType,
cancleToken,
withCredentials,
xsrfCookieName,
xsrfHeaderName,
onDownloadProgress,
onUploadProgress
} = config;
const request = new XMLHttpRequest();
request.open(method.toUpperCase(),url!,true);
configureRequest();
addEvents();
processHeaders();
proccessCancel();
request.send(data);
function configureRequest(): void{
if(responseType) request.responseType = responseType;
// 超时操作
if(timeout) request.timeout = timeout;
if(withCredentials) request.withCredentials = withCredentials;
}
function addEvents():void{
request.onreadystatechange = function handleLoad() {
if(request.readyState !== 4) {
return;
}
if(request.status === 0) {
// 网络错误和超时错误时 status为 0
return;
}
const responseHeaders = parseHeaders(request.getAllResponseHeaders());
const responseDate = responseType !== 'text' ? request.response : request.responseText;
const response:AxiosResponse = {
data:responseDate,
status:request.status,
statusText: request.statusText,
headers: responseHeaders,
config,
request,
}
handleResponse(response);
}
// 请求错误
request.onerror = function handleError() {
reject(createError('Network Error',config,null,request));
}
// 超时错误
request.ontimeout = function handleTimeout() {
reject(createError(`Timeout of ${timeout} ms exceeded`,config,'ECONNABORTED',request));
}
if(onDownloadProgress) {
request.onprogress = onDownloadProgress;
}
if(onUploadProgress) {
request.upload.onprogress = onUploadProgress;
}
}
function processHeaders():void {
if(isFormData(data)) {
delete headers['Content-Type']
}
if((withCredentials || isURLsameOrigin(url!)) && xsrfCookieName){
console.log('执行了',xsrfCookieName);
const xsrfValue = cookie.read(xsrfCookieName);
console.log(xsrfValue);
if(xsrfValue && xsrfHeaderName) {
headers[xsrfHeaderName] = xsrfValue;
}
};
// 错误结束
Object.keys(headers).forEach((name) => {
if(data === null && name.toLocaleLowerCase() === 'content-type') {
delete headers[name];
} else {
request.setRequestHeader(name,headers[name]);
}
})
}
function proccessCancel():void {
if(cancleToken) {
cancleToken.promise.then(reason => {
request.abort()
reject(reason)
})
}
}
function handleResponse(response: AxiosResponse) : void{
if(response.status >= 200 && response.status < 300) {
reslove(response);
} else {
reject(createError(`Request failed with status code ${response.status}`,config,null,request,response));
}
}
})
}
从以上代码可以看出，我将以前的代码简单的归了类， 依次执行 configureRequest、addEvents、processHeaders、proccessCancel 这四个函数，组合在进行发送
HTTP auth
HTTP协议中的 Authorization 请求消息头含有服务器用于验证用户代理身份的凭证，通常会在服务器返回401 Unauthorized 状态码以及WWW-Authenticate 消息头之后在后续请求中发送此消息头。
axios 中可以通过 auth 来设置 Authorization ，个人感觉没太大用。
types/index.ts
// ...
export interface AxiosRequestConfig {
// ...
auth?:AxiosBasicCredentials,
// ...
}
// ...
export interface AxiosBasicCredentials {
username: string,
password: string,
}
core/xhr.ts
if(auth) {
headers['Authorization'] = 'Basic ' + `${btoa(auth.username)}:${btoa(auth.password)}`;
}
就这样就行了，不过使用的话还是要配合后台的。
自定义合法状态码
我们默认的合法状态码( status )是 200 - 300，我们可以通过 validateStatus 函数来自定义合法状态
types/index.ts
export interface AxiosRequestConfig {
// ...
validateStatus?:(status:number) => boolean,
// ...
}
core/xhr.ts
function processHeaders():void {
// ...
if(auth) {
headers['Authorization'] = 'Basic ' + `${btoa(auth.username)}:${btoa(auth.password)}`;
}
// ...
}
使用
axios.get('/more/304',{
validateStatus(status){
return status >= 200 && status < 400
}
}).then(res => {
console.log(res)
}).catch((e) =>{
console.log(e.message);
})
自定义参数解析规则
看名字应该理解，用户自己定义 url 产生的解析规则
types/index.ts
export interface AxiosRequestConfig {
// ...
paramsSerializer?:(params: any) => string,
// ...
}
helpers/url.ts
export function buildURL(url: string, params?: any, paramsSerializer?:(params:any) => string):string {
if(!params) return url;
let serializedParams;
if(paramsSerializer) {
serializedParams = paramsSerializer(params);
} else if(isURLSearchParams(params)){
serializedParams = params.toString()
}else {
const parts:string[] = [];
Object.keys(params).forEach((key) => {
const val = params[key];
if(val === null || typeof val === 'undefined') {
return
}
let values = [];
if(Array.isArray(val)) {
values = val;
key += '[]';
}else {
values = [val];
}
values.forEach((val) => {
if(isDate(val)){
val = val.toISOString();
}else if(isPlainObject(val)) {
val = JSON.stringify(val);
}
parts.push(`${encode(key)}=${encode(val)}`);
})
})
serializedParams = parts.join('&');
}
if(serializedParams) {
const markIndex = url.indexOf('#');
if(markIndex !== -1) {
url = url.slice(0,markIndex);
}
url += (url.indexOf('?') === -1 ? '?' : '&') + serializedParams;
}
return url;
}
这个函数分三种情况：paramsSerializer 有的话，就进行自定义的参数解析; params 是否是 URLSearchParams ;默认解析情况
helpers/util.ts
export function isURLSearchParams(val: any): val is URLSearchParams{
return typeof val !== 'undefined' && val instanceof URLSearchParams
}
core/dispatchRequest.ts
function transformURL (config: AxiosRequestConfig) :string {
const {url,params,paramsSerializer} = config;
return buildURL(url!,params,paramsSerializer);
}
baseURL
就是我们访问同一个域名下的多个接口时，我们不希望每次发送请求都填写完整的 url，可以用这个参数进行配合
types/index.ts
export interface AxiosRequestConfig {
baseURL?:string,
}
helpers/url.ts
export function isAbsoluteURL(url:string): boolean {
return /(^[a-z][a-z\d\+\-\.]*:])?\/\//i.test(url)
}
export function combineURL(baseURL:string, relativeURL?:string):string {
return relativeURL ? baseURL.replace(/\/+$/,'') + '/' +relativeURL.replace(/^\/+/, ''): baseURL
}
前一个函数用来判断是否是绝对url，后一个函数进行url地址连接
core/dispatchRequest.ts
function transformURL (config: AxiosRequestConfig) :string {
let {url,params,paramsSerializer,baseURL} = config;
if(baseURL && !isAbsoluteURL(url)) {
url = combineURL(baseURL,url);
}
return buildURL(url!,params,paramsSerializer);
}
这里进行完整的url地址拼接
我觉得这些函数已经够用了，其他的一些很小众的函数我就不写了。