之前写过使用python抓取有路网图书信息,见http://www.cnblogs.com/dyf6372/p/3529703.html。
最近想学习一下Node.js,所以想试试手,比较一下http抓取上的性能,采用事件驱动的Node.js比python好一些,以下上代码(刚学还未优化):
var http = require(‘http‘);
var iconv = require(‘iconv-lite‘);
var url = require(‘./gb2312_url_encode.js‘);
function getHtmlOptions(path){
return {
hostname : ‘www.youlu.net‘,
port : 80,
path : path,
method : ‘GET‘,
headers : {
‘User-Agent‘ : ‘Mozilla/5.0 (Macintosh; Intel Mac OS X 10_9_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/32.0.1700.77 Safari/537.36‘
}
}
}
function getAllNumber(str){
var re = /共有图书数量\r\n\s*[0-9]*/;
var n_str = str.match(re)[0];
re = /[0-9]{1,}/;
return n_str.match(re)[0];
}
function getDetailList(str){
var re = /\"\/\d+.*"/g;
var n_array = str.match(re);
//console.log(n_array);
var result_array = [];
if(n_array == null){
return [];
}
for(var i=0;i<n_array.length;i++){
var tmp = n_array[i];
re = /\d+/;
var tmp_item = tmp.match(re);
//console.log(tmp_item[0]);
if(result_array.indexOf(tmp_item[0])<0){
re = /alt=\".*\"/;
var n_tmp_item = tmp.match(re);
if(n_tmp_item == null) continue;
var book_name = n_tmp_item[0].substring(5);
book_name = book_name.substring(0,book_name.length-1);
result_array.push(tmp_item[0]);
searchDetail(tmp_item[0],book_name);
}
}
return result_array;
}
function getRealBookNumber(str,book_name,url){
re = /startRequestBookBuyLink(.*)/;
n_array = str.match(re);
var num = n_array[0].split(‘,‘)[3];
num = num.substring(2,num.length-1);
if(num > 0){
console.log("------------------------------------");
console.log(book_name);
console.log("数目:"+num+" url:"+url);
}
}
function firstSearch(query_book_name){
var options = getHtmlOptions(‘/search/result/default.aspx?isbn=&publisherName=&author=&bookName=‘+query_book_name);
var req = http.request(options,function(res){
if(res.statusCode != 200){
console.log("请求/search/result/default.aspx?isbn=&publisherName=&author=&bookName="+query_book_name+"发生错误了:请求返回非200,返回码:"+res.statusCode+"\n");
return;
}
var chunks = [];
var size = 0;
res.on(‘data‘,function(chunk){
chunks.push(chunk);
size += chunk.length;
});
res.on(‘end‘,function(){
var returnMsg = Buffer.concat(chunks,size);
var nreturnMsg = iconv.decode(returnMsg,‘gb2312‘);
var allNumber = getAllNumber(nreturnMsg);
if(allNumber>0){
var allPage = (allNumber/20+0.5).toFixed(0);
console.log("该图书数目为:"+allNumber);
console.log("共有页数:"+allPage);
for(var i = 1; i<=allPage; i++){
searchEachPage(query_book_name,i,allNumber);
}
}else{
console.log("该图书数目为0."+"\n");
}
});
});
req.on(‘error‘, function(e) {
console.log(‘problem with request: ‘ + e.message);
});
req.end();
}
function searchEachPage(query_book_name,pageIndex,rowCount){
var options = getHtmlOptions("/search/result/?isbn=&publisherName=&author=&bookName="+query_book_name+"&pageIndex="+pageIndex+"&rowCount="+rowCount+"&searchIn=");
var req = http.request(options,function(res){
if(res.statusCode != 200){
console.log("请求"+"/search/result/?isbn=&publisherName=&author=&bookName="+query_book_name+"&pageIndex="+pageIndex+"&rowCount="+rowCount+"&searchIn="+"发生错误了:请求返回非200,返回码:"+res.statusCode+"\n");
return;
}
var chunks = [];
var size = 0;
res.on(‘data‘,function(chunk){
chunks.push(chunk);
size += chunk.length;
});
res.on(‘end‘,function(){
var returnMsg = Buffer.concat(chunks,size);
var nreturnMsg = iconv.decode(returnMsg,‘gb2312‘);
getDetailList(nreturnMsg);
});
});
req.on(‘error‘, function(e) {
console.log(‘problem with request: ‘ + e.message);
});
req.end();
}
function searchDetail(detail_number,book_name){
var options = getHtmlOptions("/"+detail_number);
var req = http.request(options,function(res){
if(res.statusCode != 200){
console.log("请求"+"/"+detail_number+"发生错误了:请求返回非200,返回码:"+res.statusCode+"\n");
return;
}
var chunks = [];
var size = 0;
res.on(‘data‘,function(chunk){
chunks.push(chunk);
size += chunk.length;
});
res.on(‘end‘,function(){
var returnMsg = Buffer.concat(chunks,size);
var nreturnMsg = iconv.decode(returnMsg,‘gb2312‘);
getRealBookNumber(nreturnMsg,book_name,"http://www.youlu.net/"+detail_number);
});
});
req.on(‘error‘, function(e) {
console.log(‘problem with request: ‘ + e.message);
});
req.end();
}
var query_book_name= url.URLEncode(‘java‘);
firstSearch(query_book_name);
使用node.js抓取有路网图书信息(原创)