node.js练手--抓百度贴吧妹子图

模拟的是 http://www.oschina.net/code/snippet_226106_23414 这个python程序

只是用node.js翻写一遍，练习练习

var baidu_base_url = 'http://tieba.baidu.com';

var http = require('http');
var url = require('url').parse(baidu_base_url + '/f?ie=utf-8&kw=%E5%A7%90%E8%84%B1');
var iconv = require('iconv-lite');
var BufferHelper = require('bufferhelper');
var $ = require('jquery');
var _ = require('underscore');
var saveRoot = "O:\\baidu\\"; //保存文件的根目录
var fs = require('fs');

String.prototype.replaceAll = function(s1, s2) {
	var demo = this
	while (demo.indexOf(s1) != - 1)
	demo = demo.replace(s1, s2);
	return demo;
}

function htmlBufferget(Url, callback) {
	http.get(Url, function(res) {
		var bufferHelper = new BufferHelper();
		res.on('data', function(chunk) {
			bufferHelper.concat(chunk);
		});
		res.on('end', function() {
			callback(bufferHelper.toBuffer());
		});
	});
}

//获取页面
function htmlget(Url, callback) {
	http.get(Url, function(res) {
		var bufferHelper = new BufferHelper();
		res.on('data', function(chunk) {
			bufferHelper.concat(chunk);
		});
		res.on('end', function() {
			var html = iconv.decode(bufferHelper.toBuffer(), 'GBK');
			callback($(html));
		});
	});
}

// 获取帖子中的图片地址
function getTieZiImg(url, fold) {
	htmlget(url, function(html) {
		html.find('img.BDE_Image').each(function(i, el) {
			var $img = $(el);
			var imgUrl = $img.attr('src');
			htmlBufferget(imgUrl, function(buffer) {
				var fileName = fold + "/" + i + ".png";
				fs.writeFile(fileName, buffer, 'binary', function(err) {
					if (err) throw err ;
					console.log(fileName + '  File saved.');
				});
			});
		});
	});
}

//主方法
htmlget(url, function(html) {
	html.find('a.j_th_tit').each(function(i, el) {
		var $a = $(el);
		var tieziUrl = baidu_base_url + $a.attr("href");
		var foldID = $a.attr("href").toString().replaceAll("/p/", "");
		var title = $a.html();
		//目录中的特殊字符
		title = title.replaceAll("/", "");
		title = title.replaceAll("?", "");
		title = title.replaceAll(",", "");
		title = title.replaceAll(":", "");

		//使用闭包在for中模拟多个线程
		(function(tieziUrl, title, foldID) {
			_.delay(function() {
				var fold = saveRoot + title;
				var exists = fs.existsSync(fold);
				console.log(fold);
				if (!exists) {
					console.log("不存在目录" + fold);
					fs.mkdirSync(fold);
				}
				getTieZiImg(tieziUrl, fold);
			},
			10);
		})(tieziUrl, title, foldID);
	});
});

2）修改保存目录