小二助手（react应用框架）-http访问

浏览地址http://118.25.217.253:4000 账号test密码123   qq讨论群:836719189

要写这个系统，就需要数据来源，让我们先来看看如果通过客户端调用服务端api拿到数据

http访问服务端api我直接使用了XMLHttpRequest，并没用使用其它第三方组件。

用户通过登录界面登录获得token，把token写入到cookie，后面的api调用从cookie取出token写入到httpheader，这样登录后的每次请求都是带token的，都是安全调用。

见下面的HttpService类：

import Cookie from './cookie'

export default class HttpService {
    static query(config) {
        config = config || {};
        var params = HttpService.formatParams(config.data);

        var request = new XMLHttpRequest();        
        request.onreadystatechange = function () {
            if (request.readyState === 4) {
                var status = request.status;
                if (status >= 200 && status < 300) {
                    var res = JSON.parse(request.responseText);
                    config.success && config.success(res);
                } else {
                    //return config.fail && config.fail(status);
                    Cookie.delete('token');
                    window.location='/';
                }
            }
        };        
        request.open('GET', config.url + "?" + params, true);
        request.setRequestHeader("Authorization", 'Bearer '+Cookie.get('token'));
        request.send(null);
    }

    static jsonp(config) {
        config = config || {};

        var params = HttpService.formatParams(config.data);
        var Scrip=document.createElement('script');
        Scrip.src = config.url + "?" + params + "&jsoncallback=HttpService.jsonpCallback";
        this.callback = config.success;

        document.body.appendChild(Scrip);
    }

    static jsonpCallback(e) {
        this.callback(e);
    }

    static save(config) {
        config = config || {};

        var params = HttpService.formatParams(config.data);
        var request = new XMLHttpRequest();        
        request.onreadystatechange = function () {
            if (request.readyState === 4) {
                var status = request.status;
                if (status >= 200 && status < 300) {
                    var res = JSON.parse(request.responseText);
                    console.log(res);
                    config.success && config.success(res);
                } else {
                    //config.fail && config.fail(status);
                    Cookie.delete('token');
                    window.location='/';
                }
            }
        };
        request.open("POST", config.url, true);
        request.setRequestHeader("Authorization", 'Bearer '+Cookie.get('token'));
        request.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
        request.send(params);
    }

    static uploadFile(cfg) {
        var config = cfg || {};
        var xhr;
        var fileObj = config.file; // js 获取文件对象
        var url = config.url; // 接收上传文件的后台地址
        var form = new FormData(); // FormData 对象
        form.append(config.name, fileObj); // 文件对象
        xhr = new XMLHttpRequest();  // XMLHttpRequest 对象
        xhr.open("post", url, true); //post方式，url为服务器请求地址，true 该参数规定请求是否异步处理。
        xhr.onreadystatechange = function () {
            if (xhr.readyState === 4) {
                var status = xhr.status;
                if (status >= 200 && status < 300) {
                    var res = JSON.parse(xhr.responseText);
                    console.log(res);
                    config.success && config.success(res);
                } else {
                    config.fail && config.fail(status);
                }
            }
        };
        xhr.send(form); //开始上传，发送form数据
    }

    static formatParams(data) {
        var arr = [];
        for (var name in data) {
            arr.push(encodeURIComponent(name) + "=" + encodeURIComponent(data[name]));
        }
        arr.push(("v=" + Math.random()).replace(".", ""));
        return arr.join("&");
    }
}

然后封装了两个常用的调用方法，api调用时打开数据加载提示，加载出错提示错误信息，加载成功执行成功事件。

static httpsave(url, data, func, showloding) {
        if (showloding) {
            CrossComponentAccess.showDataLoading();
        }
        HttpService.save({
            url: this.ApiUrl + url,
            data: data,
            success: res => {
                if (showloding) {
                    CrossComponentAccess.hideDataLoading();
                }
                if (res.succeed) {
                    func(res);
                }
                else {
                    CrossComponentAccess.showPromptDialog(res.body);
                }
            }
        });
    }

    static httpquery(url, data, func, showloding) {
        if (showloding) {
            CrossComponentAccess.showDataLoading();
        }
        HttpService.query({
            url: this.ApiUrl + url,
            data: data,
            success: res => {
                if (showloding) {
                    CrossComponentAccess.hideDataLoading();
                }
                if (res.succeed) {
                    func(res);
                }
                else {
                    CrossComponentAccess.showPromptDialog(res.body);
                }
            }
        });
    }

上面两个方法里面的CrossComponentAccess类，通过事件通知调用显示数据加载提升和操作完的提示。

所有的对服务端的api访问都是在下面ServerApi这个类里面的。调用成功后使用通知中心EventNotificationCenter把数据广播出去

import HttpService from './http-service';
import EventNames from '../config/event-names'
import EventNotificationCenter from './event-notification-center'
import CrossComponentAccess from './cross-component-access'

export default class ServerApi {
    static ApiUrl = "http://118.25.217.253:8010";
    //static ApiUrl = "http://localhost:53418";
    //static ApiUrl = "http://118.25.217.253:4010";

    static httpsave(url, data, func, showloding) {
        if (showloding) {
            CrossComponentAccess.showDataLoading();
        }
        HttpService.save({
            url: this.ApiUrl + url,
            data: data,
            success: res => {
                if (showloding) {
                    CrossComponentAccess.hideDataLoading();
                }
                if (res.succeed) {
                    func(res);
                }
                else {
                    CrossComponentAccess.showPromptDialog(res.body);
                }
            }
        });
    }

    static httpquery(url, data, func, showloding) {
        if (showloding) {
            CrossComponentAccess.showDataLoading();
        }
        HttpService.query({
            url: this.ApiUrl + url,
            data: data,
            success: res => {
                if (showloding) {
                    CrossComponentAccess.hideDataLoading();
                }
                if (res.succeed) {
                    func(res);
                }
                else {
                    CrossComponentAccess.showPromptDialog(res.body);
                }
            }
        });
    }

    static login(loginName, password) {
        this.httpsave('/User/Login', { loginName: loginName, password: password }, res => {
            EventNotificationCenter.send(EventNames.OnLoginBack, { uid: res.body.user.id, uname: res.body.user.loginName, uroles: res.body.user.roles, token: res.body.token });
        }, true);
    }

    static listDataPage(apicontroller, searchText, currentPage, pageSize, urlpars) {
        this.httpquery('/' + apicontroller + '/List', { searchText: searchText, pageIndex: currentPage, pageSize: pageSize, urlpar: urlpars }, res => {
            EventNotificationCenter.send(apicontroller + "_List", res.body);
            if (apicontroller === "Knowledge") {
                EventNotificationCenter.send(EventNames.KnowledgeCategoryMenu, res.body.category);
            }
            if (apicontroller === "KnowledgeCategory") {
                EventNotificationCenter.send(EventNames.KnowledgeCategoryMenu, res.body.dataSource);
            }
            if (apicontroller === "FlowAccount") {
                EventNotificationCenter.send(EventNames.BankAccountMenu, res.body.allBankAccount);
            }
            if (apicontroller === "BankAccount") {
                EventNotificationCenter.send(EventNames.BankAccountMenu, res.body.dataSource);
            }
            if (apicontroller === "AdvertisingCompany") {
                EventNotificationCenter.send(EventNames.ADMenu, res.body.dataSource);
            }
            if (apicontroller === "AdvertisingSpace") {
                EventNotificationCenter.send(EventNames.ADMenu, res.body.company);
            }
            if (apicontroller === "Task") {
                EventNotificationCenter.send(EventNames.TaskMenu, res.body.allExecutor);
            }
        }, false);
    }

    static deleteDataPage(apicontroller, ids) {
        this.httpsave('/' + apicontroller + '/Delete', { ids: ids }, res => {
            EventNotificationCenter.send(apicontroller + "_Delete", res.body);
        }, true);
    }

    static saveDataPage(apicontroller, data) {
        this.httpsave('/' + apicontroller + '/Save', data, res => {
            EventNotificationCenter.send(apicontroller + "_Save", res.body);
        }, true);
    }

    static infoDataPage(apicontroller, id, par) {
        this.httpquery('/' + apicontroller + '/Get', { id: id, par: par }, res => {
            EventNotificationCenter.send(apicontroller + "_Get", res.body);
        }, true);
    }

    static listFlowAccount(urlpars, project, flowCategory, beginTime, endTime, currentPage, pageSize) {
        if (beginTime !== undefined && beginTime !== "" && endTime !== undefined && endTime !== "") {
            this.httpquery('/FlowAccount/List', { urlpar: urlpars, project: project, flowCategory: flowCategory, beginTime: beginTime, endTime: endTime, pageIndex: currentPage, pageSize: pageSize }, res => {
                EventNotificationCenter.send("FlowAccount_List", res.body);
                EventNotificationCenter.send(EventNames.BankAccountMenu, res.body.allBankAccount);
            }, false);
        }
        else {
            this.httpquery('/FlowAccount/List', { urlpar: urlpars, project: project, flowCategory: flowCategory, pageIndex: currentPage, pageSize: pageSize }, res => {
                EventNotificationCenter.send("FlowAccount_List", res.body);
                EventNotificationCenter.send(EventNames.BankAccountMenu, res.body.allBankAccount);
            }, false);
        }
    }

    static listTask(excutorID, projectID, taskStepID, currentPage, pageSize, isClosed) {
        this.httpquery('/Task/List', { excutorID: excutorID, projectID: projectID, taskStepID: taskStepID, isClosed: isClosed, pageIndex: currentPage, pageSize: pageSize }, res => {
            EventNotificationCenter.send("Task_List", res.body);
            EventNotificationCenter.send(EventNames.TaskMenu, res.body.allExecutor);
        }, false);
    }

    static closeTask(ids) {
        this.httpsave('/Task/Close', { ids: ids }, res => {
            EventNotificationCenter.send("Task_Close", res.body);
        }, true);
    }
}

这章http访问里，涉及到Cookie和通知中心EventNotificationCenter在下一章介绍。