nodejs 小爬虫代码 nodejs

nodejs小爬虫代码

var http=require('http');

var cheerio = require('cheerio');

var url='http://www.imooc.com/learn/348';

function filterChapters(html){

var $=cheerio.load(html);

var chapters=$('.chapter');

var courseData = [];

chapters.each(function(item){

var chapter=$(this);

var chapterTitle=chapter.find('strong').text();

var videos=chapter.find('.video').children('li');

var chapterData={

chapterTitle:chapterTitle,

videos:[]

};

videos.each(function(item){

var video=$(this).find('.J-media-item');

var videoTitle=video.text();

var id=video.attr('href').split('video/')[1];

chapterData.videos.push({

title:videoTitle,

id:id

})

})

courseData.push(chapterData);

})

return courseData;

}

function printCourseInfo(courseData){

courseData.forEach(function(item){

var chapterTitle=item.chapterTitle;

console.log(chapterTitle+'\n');

item.videos.forEach(function(video){

console.log('【'+video.id+'】'+video.title+'\n');

});

});

}

http.get(url,function(res){

var html="";

res.on('data',function(data){

html+=data;

});

res.on('end',function(){

var courseData=filterChapters(html);

printCourseInfo(courseData);

})

}).on('error',function(){

console.log('获取课程失败');

})