全局安装typescript：
npm install -g typescript
目前版本2.0.3，这个版本不再需要使用typings命令了。但是vscode捆绑的版本是1.8的，需要一些配置工作，看本文的处理办法。
测试tsc命令：
tsc
创建要写的程序项目文件夹：
mkdir test-typescript-spider
进入该文件夹：
cd test-typescript-spider
初始化项目：
npm init
安装superagent和cheerio模块：
npm i --save superagent cheerio
安装对应的类型声明模块：
npm i -s @types/superagent --savenpm i -s @types/cheerio --save
安装项目内的typescript（必须走这一步）：
npm i --save typescript
用vscode打开项目文件夹。在该文件夹下创建tsconfig.json文件，并复制以下配置代码进去：
{ "compilerOptions": { "target": "ES6", "module": "commonjs", "noEmitOnError": true, "noImplicitAny": true, "experimentalDecorators": true, "sourceMap": false, // "sourceRoot": "./", "outDir": "./out" }, "exclude": [ "node_modules" ]} 在vscode打开“文件”-“首选项”-“工作区设置”
在settings.json中加入（如果不做这个配置，vscode会在打开项目的时候提示选择哪个版本的typescript）：{ "typescript.tsdk": "node_modules/typescript/lib"} 创建api.ts文件，复制以下代码进去：
import superagent = require('superagent');import cheerio = require('cheerio');export const remote_get = function(url: string) { const promise = new Promise (function (resolve, reject) { superagent.get(url) .end(function (err, res) { if (!err) { resolve(res); } else { console.log(err) reject(err); } }); }); return promise;} 创建app.ts文件，书写测试代码：
import api = require('./api');const go = async () => { let res = await api.remote_get('http://www.baidu.com/'); console.log(res.text);}go(); 执行命令：
tsc
然后：
node out/app
观察输出是否正确。
现在尝试抓取的第一页文章链接。
修改app.ts文件，代码如下：import api = require('./api');import cheerio = require('cheerio');const go = async () => { const res = await api.remote_get('http://cnodejs.org/'); const $ = cheerio.load(res.text); let urls: string[] = []; let titles: string[] = []; $('.topic_title_wrapper').each((index, element) => { titles.push($(element).find('.topic_title').first().text().trim()); urls.push('http://cnodejs.org/' + $(element).find('.topic_title').first().attr('href')); }) console.log(titles, urls);}go(); 观察输出，文章的标题和链接都已获取到了。
现在尝试深入抓取文章内容
import api = require('./api');import cheerio = require('cheerio');const go = async () => { const res = await api.remote_get('http://cnodejs.org/'); const $ = cheerio.load(res.text); $('.topic_title_wrapper').each(async (index, element) => { let url = ('http://cnodejs.org' + $(element).find('.topic_title').first().attr('href')); const res_content = await api.remote_get(url); const $_content = cheerio.load(res_content.text); console.log($_content('.topic_content').first().text()); })}go(); 可以发现因为访问服务器太迅猛，导致出现很多次503错误。
解决：添加helper.ts文件：export const wait_seconds = function (senconds: number) { return new Promise(resolve => setTimeout(resolve, senconds * 1000));} 修改api.ts文件为：
import superagent = require('superagent');import cheerio = require('cheerio');export const get_index_urls = function () { const res = await remote_get('http://cnodejs.org/'); const $ = cheerio.load(res.text); let urls: string[] = []; $('.topic_title_wrapper').each(async (index, element) => { urls.push('http://cnodejs.org' + $(element).find('.topic_title').first().attr('href')); }); return urls;}export const get_content = async function (url: string) { const res = await remote_get(url); const $ = cheerio.load(res.text); return $('.topic_content').first().text();}export const remote_get = function (url: string) { const promise = new Promise (function (resolve, reject) { superagent.get(url) .end(function (err, res) { if (!err) { resolve(res); } else { console.log(err) reject(err); } }); }); return promise;} 修改app.ts文件为：
import api = require('./api');import helper = require('./helper');import cheerio = require('cheerio');const go = async () => { let urls = await api.get_index_urls(); for (let i = 0; i < urls.length; i++) { await helper.wait_seconds(1); let text = await api.get_content(urls[i]); console.log(text); }}go(); 观察输出可以看到，程序实现了隔一秒再请求下一个内容页。
现在尝试把抓取到的东西存到数据库中。
安装mongoose模块：npm i mongoose --savenpm i -s @types/mongoose --save
然后建立Scheme。先创建models文件夹：
mkdir models
在models文件夹下创建index.ts：
import * as mongoose from 'mongoose';mongoose.connect('mongodb://127.0.0.1/cnodejs_data', { server: { poolSize: 20 }}, function (err) { if (err) { process.exit(1); }});// modelsexport const Article = require('./article'); 在models文件夹下创建IArticle.ts:
interface IArticle { title: String; url: String; text: String;}export = IArticle; 在models文件夹下创建Article.ts:
import mongoose = require('mongoose');import IArticle = require('./IArticle');interface IArticleModel extends IArticle, mongoose.Document { }const ArticleSchema = new mongoose.Schema({ title: { type: String }, url: { type: String }, text: { type: String },});const Article = mongoose.model ("Article", ArticleSchema);export = Article; 修改api.ts为：
import superagent = require('superagent');import cheerio = require('cheerio');import models = require('./models');const Article = models.Article;export const get_index_urls = async function () { const res = await remote_get('http://cnodejs.org/'); const $ = cheerio.load(res.text); let urls: string[] = []; $('.topic_title_wrapper').each((index, element) => { urls.push('http://cnodejs.org' + $(element).find('.topic_title').first().attr('href')); }); return urls;}export const fetch_content = async function (url: string) { const res = await remote_get(url); const $ = cheerio.load(res.text); let article = new Article(); article.text = $('.topic_content').first().text(); article.title = $('.topic_full_title').first().text().replace('置顶', '').replace('精华', '').trim(); article.url = url; console.log('获取成功：' + article.title); article.save();}export const remote_get = function (url: string) { return new Promise ((resolve, reject) => { superagent.get(url) .end(function (err, res) { if (!err) { resolve(res); } else { reject(err); } }); });} 修改app.ts为：
import api = require('./api');import helper = require('./helper');import cheerio = require('cheerio');(async () => { try { let urls = await api.get_index_urls(); for (let i = 0; i < urls.length; i++) { await helper.wait_seconds(1); await api.fetch_content(urls[i]); } } catch (err) { console.log(err); } console.log('完毕！');})(); 执行
tscnode out/app
观察输出，并去数据库检查一下
可以发现入库成功了！补充：remote_get方法的改进版，实现错误重试和加入代理服务器.
放弃了superagent库，用的request库，仅供参考：//config.retries = 3;let current_retry = config.retries || 0;export const remote_get = async function (url: string, proxy?: string) { //每次请求都先稍等一下 await wait_seconds(2); if (!proxy) { proxy = ''; } const promise = new Promise (function (resolve, reject) { console.log('get: ' + url + ', using proxy: ' + proxy); let options: request.CoreOptions = { headers: { 'Cookie': '', 'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/53.0.2785.143 Safari/537.36', 'Referer': 'https://www.baidu.com/' }, encoding: 'utf-8', method: 'GET', proxy: proxy, timeout: 3000, } request(url, options, async function (err, response, body) { console.log('got:' + url); if (!err) { body = body.toString(); current_retry = config.retries || 0; console.log('bytes:' + body.length); resolve(body); } else { console.log(err); if (current_retry <= 0) { current_retry = config.retries || 0; reject(err); } else { console.log('retry...(' + current_retry + ')') current_retry--; try { let body = await remote_get(url, proxy); resolve(body); } catch (e) { reject(e); } } } }); }); return promise;} 另外，IArticle.ts和Article.ts合并为一个文件，可能更好，可以参考我另一个model的写法：
import mongoose = require('mongoose');interface IProxyModel { uri: string; ip: string; port:string; info:string;}export interface IProxy extends IProxyModel, mongoose.Document { }const ProxySchema = new mongoose.Schema({ uri: { type: String },// ip: { type: String },// port: { type: String },// info: { type: String },//});export const Proxy = mongoose.model ("Proxy", ProxySchema); 导入的时候这么写就行了：
import { IProxy, Proxy } from './models'; 其中Proxy可以用来做new、find、where之类的操作:
let x = new Proxy();let xx = await Proxy.find({});let xxx = await Proxy.where('aaa',123).exec(); 而IProxy用于实体对象的传递，例如
function xxx(p:IProxy){}