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爬虫_promise_20161005_学习人数拿不到

jokeryip4025914
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var http = require('http')
var Promise = require('bluebird')
var url = 'http://www.imooc.com/learn/348'
var cheerio = require('cheerio')
var baseUrl = 'http://www.imooc.com/learn/'
vedioIds = ['348','637']

function filterChapters(html){
var $ = cheerio.load(html)
var chapters = $('.chapter')

// coureData = {
//     title : title,
//     number : number,
//     vedios : [{
//         chapterTitle : '',
//         vedios : [
//             title : '',
//             id : ''
//         ]
//     }]
// }
//meta-value js-learn-num
// var path = $('.path').length
// console.log(path);
var title = $('.path').children('a').children('span').text().trim()
//var number = $('.static-item.l > span.js-learn-num').;
var level = $($('.static-item.l')[1]).find('span').last().text().trim()
console.log(level)
//var number = parseInt($($('.static-item.l ')[0]).text().trim(), 10)
//console.log(number)
var courseData = {
    title : title,
    number : 0,
    vedios : []
}

chapters.each(function(item){
    var chapter  = $(this)
    $('.chapter-content').remove()
    $('.moco-btn').remove()
    var chapterTitile = chapter.find('strong').text().trim()

    var chapterData = {
        chapterTitle : chapterTitile,
        videos : []
    }

    var videos = chapter.find('ul').children('li')
    videos.each(function(item){
        var vedio = $(this)
        var vedioTitle = vedio.find('.J-media-item').text().trim()
        var vedioId = vedio.find('a').attr('href').split('video/')[1]

        chapterData.videos.push({
            title : vedioTitle,
            id : vedioId
        })
    })

    courseData.vedios.push(chapterData)
})

return courseData

}

function printCourse(courseData){
courseData.forEach(function(item){
var chapterTitle = item.chapterTitle
console.log(chapterTitle);
var vedios = item.videos
vedios.forEach(function(item){
console.log('[' + item.id + ']' + item.title);
})
})
}

function getPageAsync(url){
return new Promise(function(resolve, reject){
console.log('正在爬取 ' + url);

    http
    .get(url, function(res){
    var html = ''

        res.on('data', function(data){
            html += data
        })

        res.on('end', function(){
            //console.log(html);
            resolve(html)
            //var courseData = filterChapters(html)
            //printCourse(courseData)
        })
    })
    .on('error', function(e){
        reject(e)
        console.log('获取课程异常')
    })
})

}

function printCourse2(coursesData){
coursesData.forEach(function(item){
var title = item.title
console.log(title)
var vedios = item.vedios
vedios.forEach(function(item){
var chapterTitle = item.chapterTitle
console.log(chapterTitle)
var chapterVedios = item.videos
chapterVedios.forEach(function(item){
console.log('['+item.id+'] ' + item.title)
})
})
})
}

var fetchCourseArray = []

vedioIds.forEach(function(id){
fetchCourseArray.push(getPageAsync(baseUrl + id))
})

//getPageAsync(url)
Promise
.all(fetchCourseArray)
.then(function(pages){
//console.log("pages: " + pages)
var coursesData = []
//console.log("pages : " + pages.length)
pages.forEach(function(html){
//console.log("html : " + html)
//var course = filterChapters(html)
var course = filterChapters(html)
coursesData.push(course)

        printCourse2(coursesData)

    })
})
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