fetch方法封装

/* http.js */
import 'whatwg-fetch'
 
// HTTP 工具类
export default class Http {
    static async request(method, url, data) {
        const param = {
            method: method,
            headers: {
                'Content-Type': 'application/json'
            }
        };
 
        if (method === 'GET') {
            url += this.formatQuery(data)
        } else {
            param['body'] = JSON.stringify(data)
        }
 
        // Tips.loading(); // 可调用 loading 组件
 
        return fetch(url, param).then(response => this.isSuccess(response))
                .then(response => {
                    return response.json()
            })
    }
 
    // 判断请求是否成功
    static isSuccess(res) {
        if (res.status >= 200 && res.status < 300) {
            return res
        } else {
            this.requestException(res)
        }
    }
 
    // 处理异常
    static requestException(res) {
        const error = new Error(res.statusText)
 
        error.response = res
 
        throw error
    }
     
    // url处理
    static formatQuery(query) {
        let params = [];
 
        if (query) {
            for (let item in query) {
                let vals = query[item];
                if (vals !== undefined) {
                    params.push(item + '=' + query[item])
                }
            }
        }
        return params.length ? '?' + params.join('&') : '';
    }
     
    // 处理 get 请求
    static get(url, data) {
        return this.request('GET', url, data)
    }
     
    // 处理 put 请求
    static put(url, data) {
        return this.request('PUT', url, data)
    }
     
    // 处理 post 请求
    static post(url, data) {
        return this.request('POST', url, data)
    }
     
    // 处理 patch 请求
    static patch(url, data) {
        return this.request('PATCH', url, data)
    }
     
    // 处理 delete 请求
    static delete(url, data) {
        return this.request('DELETE', url, data)
    }
}