尝试获取了人数 但是感觉实现不太优雅
var http = require('http');
var baseUrl = 'http://www.imooc.com/learn/';
var learnNumber_baseUrl = 'http://www.imooc.com/course/AjaxCourseMembers?ids='
var cheerio = require('cheerio');
var videosId = [728,637,348,259,197,134,75];
function filerChapters(pageData){
var html = pageData.html;
var $ = cheerio.load(html);
var chapters = $('.chapter');
var courseData = {
title:$('.hd h2').text(),
number:pageData.number,
id:$('.person-num').attr('href').split('/')[2],
videos:[]
};
chapters.each(function(item){
var chapter = $(this);
var chapterTitle = chapter.find('h3').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().trim();
var id = video.attr('href').split('video/')[1];
var videoData = {
title:videoTitle,
id:id
}
chapterData.videos.push(videoData);
});
courseData.videos.push(chapterData);
});
return courseData;
}
function printCourseData(coursesData){
coursesData.forEach(function(courseData){
console.log('\n');
console.log(' ######### '+courseData.title + ' [学习人数：' + courseData.number + '] #########\n');
courseData.videos.forEach(function(item){
var chapterTitle = item.chapterTitle;
console.log(chapterTitle );
item.videos.forEach(function(video){
console.log(' [' + video.id+ ']' + video.title.trim().split('(')[0]);
})
})
})
}
function getPageAsync(url){
return new Promise(function(resolve, reject){
http.get(url,function(res){
var html = '';
res.on('data',function(data){
html += data;
});
res.on('end',function(){
resolve(html)
});
}).on('error',function(){
console.log('error');
})
})
}
function getLearnDataAsync(html){
return new Promise(function(resolve,reject){
var $ = cheerio.load(html)
var id = $('.person-num').attr('href').split('/')[2]
var pageData = {
html:html,
number:0
}
var db = ''
http.get(learnNumber_baseUrl+id,function(res){
res.on('data',function(data){
db += data;
db = JSON.parse(db)
pageData.number = parseInt(db.data[0].numbers,10)
})
res.on('end',function(){
resolve(pageData);
})
}).on('error',function(){
console.log('error')
})
})
}
var promiseList = []
var coursesDataPromises = []
videosId.forEach(function(id){
promiseList.push(getPageAsync(baseUrl+id).then(function(html){
return getLearnDataAsync(html);
}))
})
Promise
.all(promiseList)
.then(function(pagesData){
var coursesData = []
pagesData.forEach(function(pageData){
coursesData.push(filerChapters(pageData))
})
printCourseData(coursesData)
})
