Generic web crawler powered by Node.js
Using npm:
$ npm install node-spider
var Spider = require('node-spider');
var spider = new Spider({
// How many requests can be run in parallel
concurrent: 5,
// How long to wait after each request
delay: 0,
// A stream to where internal logs are sent, optional
logs: process.stderr,
// Re-visit visited URLs, false by default
allowDuplicates: false,
// If `true` all queued handlers will be try-catch'd, errors go to `error` callback
catchErrors: true,
// If `true` the spider will set the Referer header automatically on subsequent requests
addReferrer: false,
// If `true` adds the X-Requested-With:XMLHttpRequest header
xhr: false,
// If `true` adds the Connection:keep-alive header and forever option on request module
keepAlive: false,
// Called when there's an error, throw will be used if none is provided
error: function(err, url) {
},
// Called when there are no more requests
done: function() {
},
//- All options are passed to `request` module, for example:
headers: { 'user-agent': 'node-spider' },
encoding: 'utf8'
});
var handleRequest = function(doc) {
// new page crawled
console.log(doc.res); // response object
console.log(doc.url); // page url
// uses cheerio, check its docs for more info
doc.$('a').each(function(i, elem) {
// do stuff with element
var href = doc.$(elem).attr('href').split('#')[0];
var url = doc.resolve(href);
// crawl more
spider.queue(url, handleRequest);
});
};
// start crawling
spider.queue('http://google.com/', handleRequest);Copyright (c) 2014, Ariel Flesler All rights reserved.
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
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Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
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Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
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