My issue is that I can't scrape a website that uses login when it renders the page using Javascript.
I can easily log in using this code:
import requests
from lxml import html
payload ={
"username":"username",
"password":"password"
}
session_requests = requests.session()
result = session_requests.get(login_url)
tree = html.fromstring(result.text)
result = session_requests.post(
login_url,
data = payload,
headers = dict(referer=login_url)
)
Then I can get some values using this code:
result = session_requests.get(agent_url, headers = dict(referer = agent_url ))
tree = html.fromstring(result.content)
needed_info = tree.xpath("//div[#class='col-md-6']/div[#class='table-responsive']/table/tbody/tr[22]/td[2]")[0].text
However, not everything is rendered.
I've also tried to use dryscrape, however, it does not work on Windows.
Selenium is just too heavy for my needs and I'm having issues installing Spynner (probably because it does not support Python 3.6?)
What would you recommend?
I just went and did it using selenium. Everything else was just too much of a hassle for this little project.
Im trying to scrape products from a web store similar to how Dropified scrapes items from Ali express,
Current Solution(the way it's set up it will only try and access the first item):
from bs4 import BeautifulSoup
import requests
import time
import re
# Get search inputs from user
search_term = raw_input('Search Term:')
# Build URL to imdb.com
aliURL = 'https://www.aliexpress.com/wholesale?SearchText=%(q)s'
payload = {'q': search_term, }
# Get resulting webpage
r = requests.get(aliURL % payload)
# Build 'soup' from webpage and filter down to the results of search
soup = BeautifulSoup(r.text, "html5lib")
titles = soup.findAll('a', attrs = {'class': 'product'})
itemURL = titles[0]["href"]
seperatemarker = '?'
seperatedURL = itemURL.split(seperatemarker, 1)[0]
seperatedURL = "http:" + seperatedURL
print seperatedURL
IR = requests.get(seperatedURL)
Isoup = BeautifulSoup(IR.text, "html5lib")
productname = Isoup.findAll('h1')
print productname
This solution works assuming that the items on the page don't require javascript if the item does it will only retrieve the initial page before the document is ready.
I realise I can use a python web driver, but I was wondering if there was any other solution to this problem that would allow for easy automation of a web scraping tool.
Checkout selenium with phantomjs. selenium and phantomjs handle most of the issues related to JS generated content on the page. You don't even need to think about these things anymore.
If you're scraping many pages and want to speed things up, you might want to do things asynchronously. For a small to mid-sized setup, you can use RQ. For larger projects you can use celery. What these tools allow you to do is scrape multiple pages at the same time(not concurrently though).
Note that the tools I've mentioned so far have nothing to do with asyncio or other async frameworks.
I tried scraping some e-commerce pages and noticed that the program was spending 80% of its time waiting for HTTP calls to return something. Using the above tools you can reduce that 80% to 10% or less.
im very new to JavaScript so be patient.
I've been trying to scrape a site and get all the product URLs in a list that i will use later in other function like this:
url='https://www.fromuthtennis.com/frm/c-10-mens-tops.aspx'
var http = require('http-get');
var request = require("request");
var cheerio = require("cheerio");
function getURLS(url) {
request(url, function(err, resp, body){
var linklist = [];
$ = cheerio.load(body);
var links = $('#productResults a');
for(valor in links) {
if(links[valor].attribs && links[valor].attribs.href && linklist.indexOf(links[valor].attribs.href) == -1){
linklist.push(links[valor].attribs.href);
}
}
var extended_links = [];
linklist.forEach(function(link){
extended_link = 'https://www.fromuthtennis.com/frm/' + link;
extended_links.push(extended_link);
})
console.log(extended_links);
})
};
This does work unless you go to the second page of items like this:
url='https://www.fromuthtennis.com/frm/c-10-mens-tops.aspx#Filter=[pagenum=2*ava=1]'
var http = require('http-get');
var request = require("request");
var cheerio = require("cheerio"); //etc...
As far as i know this happens because the content on the page is loaded dynamically.
To get the contents of the page i believe i need to use PhantomJS because that would allow me to get the html code after the page has been fully loaded, so i installed the phantomjs-node module. I want to use NodeJS to get the URL list because the rest of my code is written on it.
I've been reading a lot about PhantomJS but using the phantomjs-node is tricky and i still don't understand how could i get the URL list using it because i'm very new to JavaScript or coding in general.
If someone could guide me a little bit i'd appreciate it a lot.
Yes, you can. That page looks like it implements Google's Ajax Crawling URL.
Basically it allows websites to generate crawler friendly content for Google. Whenever you see a URL like this:
https://www.fromuthtennis.com/frm/c-10-mens-tops.aspx#Filter=[pagenum=2*ava=1]
You need to convert it to this:
https://www.fromuthtennis.com/frm/c-10-mens-tops.aspx?_escaped_fragment_=Filter%3D%5Bpagenum%3D2*ava%3D1%5D
The conversion is simply take the base path: https://www.fromuthtennis.com/frm/c-10-mens-tops.aspx, add a query param _escaped_fragment_ who's value is URL fragment Filter=[pagenum=2*ava=1] encoded into Filter%3D%5Bpagenum%3D2*ava%3D1%5D using standard URI encoding.
You can read the full specification here: https://developers.google.com/webmasters/ajax-crawling/docs/specification
Note: This does not apply to all websites, only websites that implement Google's Ajax Crawling URL. But you're in luck in this case
You can see any product you want without using dynmic content using this url:
https://www.fromuthtennis.com/frm/showproduct.aspx?ProductID={product_id}
For example to see product 37023:
https://www.fromuthtennis.com/frm/showproduct.aspx?ProductID=37023
All you have to do is for(var productid=0;prodcutid<40000;productid++) {request...}.
Another approach is to use phantom module. (https://www.npmjs.com/package/phantom). It will let you run phantom command directly from your NodeJS app
I want to scrape my college website (moodle) with node.js but I haven't found a headless browser able to do it. I have done it in python in just 10 lines of code using RoboBrowser:
from robobrowser import RoboBrowser
url = "https://cas.upc.edu/login?service=https%3A%2F%2Fatenea.upc.edu%2Fmoodle%2Flogin%2Findex.php%3FauthCAS%3DCAS"
browser = RoboBrowser()
browser.open(url)
form = browser.get_form()
form['username'] = 'myUserName'
form['password'] = 'myPassword'
browser.submit_form(form)
browser.open("http://atenea.upc.edu/moodle/")
print browser.parsed
The problem is that the website requires authentication. Can you help me? Thanks!
PD: I think this can be useful https://www.npmjs.com/package/form-scraper but I can't get it working.
Assuming you want to read a 3rd party website, and 'scrape' particular pieces of information, you could use a library such as cheerio to achieve this in Node.
Cheerio is a "lean implementation of core jQuery designed specifically for the server". This means that given a String representation of a DOM (or part thereof), cheerio can traverse it in much the same way as jQuery can.
An example from Max Ogden show how you can use the request module to grab HTML from a remote server and then pass it to cheerio:
var $ = require('cheerio')
var request = require('request')
function gotHTML(err, resp, html) {
if (err) return console.error(err)
var parsedHTML = $.load(html)
// get all img tags and loop over them
var imageURLs = []
parsedHTML('a').map(function(i, link) {
var href = $(link).attr('href')
if (!href.match('.png')) return
imageURLs.push(domain + href)
})
}
var domain = 'http://substack.net/images/'
request(domain, gotHTML)
Selenium has support for multiple languages and multiple platforms and multiple browsers.
I want to crawl the page and check for the hyperlinks in that respective page and also follow those hyperlinks and capture data from the page
Generally, browser JavaScript can only crawl within the domain of its origin, because fetching pages would be done via Ajax, which is restricted by the Same-Origin Policy.
If the page running the crawler script is on www.example.com, then that script can crawl all the pages on www.example.com, but not the pages of any other origin (unless some edge case applies, e.g., the Access-Control-Allow-Origin header is set for pages on the other server).
If you really want to write a fully-featured crawler in browser JS, you could write a browser extension: for example, Chrome extensions are packaged Web application run with special permissions, including cross-origin Ajax. The difficulty with this approach is that you'll have to write multiple versions of the crawler if you want to support multiple browsers. (If the crawler is just for personal use, that's probably not an issue.)
If you use server-side javascript it is possible.
You should take a look at node.js
And an example of a crawler can be found in the link bellow:
http://www.colourcoding.net/blog/archive/2010/11/20/a-node.js-web-spider.aspx
Google's Chrome team has released puppeteer on August 2017, a node library which provides a high-level API for both headless and non-headless Chrome (headless Chrome being available since 59).
It uses an embedded version of Chromium, so it is guaranteed to work out of the box. If you want to use an specific Chrome version, you can do so by launching puppeteer with an executable path as parameter, such as:
const browser = await puppeteer.launch({executablePath: '/path/to/Chrome'});
An example of navigating to a webpage and taking a screenshot out of it shows how simple it is (taken from the GitHub page):
const puppeteer = require('puppeteer');
(async () => {
const browser = await puppeteer.launch();
const page = await browser.newPage();
await page.goto('https://example.com');
await page.screenshot({path: 'example.png'});
await browser.close();
})();
We could crawl the pages using Javascript from server side with help of headless webkit. For crawling, we have few libraries like PhantomJS, CasperJS, also there is a new wrapper on PhantomJS called Nightmare JS which make the works easier.
There are ways to circumvent the same-origin policy with JS. I wrote a crawler for facebook, that gathered information from facebook profiles from my friends and my friend's friends and allowed filtering the results by gender, current location, age, martial status (you catch my drift). It was simple. I just ran it from console. That way your script will get privilage to do request on the current domain. You can also make a bookmarklet to run the script from your bookmarks.
Another way is to provide a PHP proxy. Your script will access the proxy on current domain and request files from another with PHP. Just be carefull with those. These might get hijacked and used as a public proxy by 3rd party if you are not carefull.
Good luck, maybe you make a friend or two in the process like I did :-)
My typical setup is to use a browser extension with cross origin privileges set, which is injecting both the crawler code and jQuery.
Another take on Javascript crawlers is to use a headless browser like phantomJS or casperJS (which boosts phantom's powers)
This is what you need http://zugravu.com/products/web-crawler-spider-scraping-javascript-regular-expression-nodejs-mongodb
They use NodeJS, MongoDB and ExtJs as GUI
yes it is possible
Use NODEJS (its server side JS)
There is NPM (package manager that handles 3rd party modules) in nodeJS
Use PhantomJS in NodeJS (third party module that can crawl through websites is PhantomJS)
There is a client side approach for this, using Firefox Greasemonkey extention. with Greasemonkey you can create scripts to be executed each time you open specified urls.
here an example:
if you have urls like these:
http://www.example.com/products/pages/1
http://www.example.com/products/pages/2
then you can use something like this to open all pages containing product list(execute this manually)
var j = 0;
for(var i=1;i<5;i++)
{
setTimeout(function(){
j = j + 1;
window.open('http://www.example.com/products/pages/ + j, '_blank');
}, 15000 * i);
}
then you can create a script to open all products in new window for each product list page and include this url in Greasemonkey for that.
http://www.example.com/products/pages/*
and then a script for each product page to extract data and call a webservice passing data and close window and so on.
I made an example javascript crawler on github.
It's event driven and use an in-memory queue to store all the resources(ie. urls).
How to use in your node environment
var Crawler = require('../lib/crawler')
var crawler = new Crawler('http://www.someUrl.com');
// crawler.maxDepth = 4;
// crawler.crawlInterval = 10;
// crawler.maxListenerCurrency = 10;
// crawler.redisQueue = true;
crawler.start();
Here I'm just showing you 2 core method of a javascript crawler.
Crawler.prototype.run = function() {
var crawler = this;
process.nextTick(() => {
//the run loop
crawler.crawlerIntervalId = setInterval(() => {
crawler.crawl();
}, crawler.crawlInterval);
//kick off first one
crawler.crawl();
});
crawler.running = true;
crawler.emit('start');
}
Crawler.prototype.crawl = function() {
var crawler = this;
if (crawler._openRequests >= crawler.maxListenerCurrency) return;
//go get the item
crawler.queue.oldestUnfetchedItem((err, queueItem, index) => {
if (queueItem) {
//got the item start the fetch
crawler.fetchQueueItem(queueItem, index);
} else if (crawler._openRequests === 0) {
crawler.queue.complete((err, completeCount) => {
if (err)
throw err;
crawler.queue.getLength((err, length) => {
if (err)
throw err;
if (length === completeCount) {
//no open Request, no unfetcheditem stop the crawler
crawler.emit("complete", completeCount);
clearInterval(crawler.crawlerIntervalId);
crawler.running = false;
}
});
});
}
});
};
Here is the github link https://github.com/bfwg/node-tinycrawler.
It is a javascript web crawler written under 1000 lines of code.
This should put you on the right track.
You can make a web crawler driven from a remote json file that opens all links from a page in new tabs as soon as each tab loads except ones that have already been opened. If you set up a with a browser extension running in a basic browser (nothing runs except the web browser and an internet config program) and had it shipped and installed somewhere with good internet, you could make a database of webpages with an old computer. That would just need to retrieve the content of each tab. You could do that for about $2000, contrary to most estimates for search engine costs. You'd just need to basically make your algorithm provide pages based on how much a term appears in the innerText property of the page, keywords, and description. You could also set up another PC to recrawl old pages from the one-time database and add more. I'd estimate it would take about 3 months and $20000, maximum.
Axios + Cheerio
You can do this with axios and cheerios. Check axios docs for response format.
const cheerio = require('cheerio');
const axios = require('axios');
//crawl
//get url
var url = 'http://amazon.com';
axios.get(url)
.then((res) => {
//response format
var body = res.data;
var statusCode = res.status;
var statusText = res.statusText;
var headers = res.headers;
var request = res.request;
var config = res.config;
//jquery
let $ = cheerio.load(body);
//example
//meta tags
var title = $('meta[name=title]').attr('content');
if(title == undefined || title == 'undefined'){
title = $('title').text();
}else{
title = title;
}
var description = $('meta[name=description]').attr('content');
var keywords = $('meta[name=keywords]').attr('content');
var author = $('meta[name=author]').attr('content');
var type = $('meta[http-equiv=content-type]').attr('content');
var favicon = $('link[rel="shortcut icon"]').attr('href');
}).catch(function (e) {
console.log(e);
});
Node-Fetch + Cheerio
You can do the same thing with node-fetch and cheerio.
fetch(url, {
method: "GET",
}).then(function(response){
//response
var html = response.text();
//return
return html;
})
.then(function(res) {
//response html
var html = res;
//jquery
let $ = cheerio.load(html);
//meta tags
var title = $('meta[name=title]').attr('content');
if(title == undefined || title == 'undefined'){
title = $('title').text();
}else{
title = title;
}
var description = $('meta[name=description]').attr('content');
var keywords = $('meta[name=keywords]').attr('content');
var author = $('meta[name=author]').attr('content');
var type = $('meta[http-equiv=content-type]').attr('content');
var favicon = $('link[rel="shortcut icon"]').attr('href');
})
.catch((error) => {
console.error('Error:', error);
});