Scrapy for dynamic data website using Angular or VueJs - python

How do I scrape data using Scrapy Framework from websites which loads data using javascript frameworks? Scrapy download the html from each page requests but some website uses js frameworks like Angular or VueJs which will load data separately.
I have tried using a combination of Scrapy,Selenium and chrome driver to retrieve the htmls which gives the rendered html with content. But when using this method I am not able to retain the session cookies set for selecting country and currency as each request is handled by a separate instance of selenium or chrome.
Please suggest if there is any alternative options to scrape the dynamic content while retaining the session.
Adding the code which i used to set the country and currency
import scrapy
from selenium import webdriver
class SettingSpider(scrapy.Spider):
name = 'setting'
allowed_domains = ['example.com']
start_urls = ['http://example.com/']
def __init__(self):
self.driver = webdriver.Chrome()
def start_requests(self):
url = 'http://www.example.com/intl/settings'
self.driver.get(response.url)
yield scrapy.Request(url, self.parse)
def parse(self, response):
csrf = response.xpath('//input[#name="CSRFToken"]/#value').extract_first().strip()
print('------------->' + csrf)
url = 'http://www.example.com/intl/settings'
form_data = {'shippingCountry': 'ARE', 'language': 'en', 'billingCurrency': 'USD', 'indicativeCurrency': '',
'CSRFToken:': csrf}
yield scrapy.FormRequest(url, formdata=form_data, callback=self.after_post)

what you said
as each request is handled by a separate instance of selenium or chrome
is not correct,
You can continue to use Selenium and i suggest you to use phantomJS instead of chrome.
i can't help more because you didn't put your code.
one example for phantomJS:
from selenium import webdriver
driver = webdriver.PhantomJS()
driver.set_window_size(1120, 800)
driver.get("https://example.com/")
driver.close()
and if you don't want to use Selenium, you can use Splash
Splash is a javascript rendering service with an HTTP API. It's a
lightweight browser with an HTTP API, implemented in Python 3 using
Twisted and QT5
as #Granitosaurus said in this question
Bonus points for it being developed by the same guys who are
developing Scrapy.

Related

Is there a way to make a dynamic web page automatically run its JavaScript when webscraping with Python?

I have been getting a lot of issues when trying to do some Python webscraping using BeautifulSoup. Since this particular web page is dynamic, I have been trying to use Selenium first in order to "open" the web page before trying to work with the dynamic content with BeautifulSoup.
The issue I am getting is that the dynamic content is only showing up in my HTML output when I manually scroll through the website upon running the program, otherwise those parts of the HTML remain empty as if I was just using BeautifulSoup by itself without Selenium.
Here is my code:
import time
from bs4 import BeautifulSoup
from selenium import webdriver
if __name__ == "__main__":
options = webdriver.ChromeOptions()
options.add_argument('--ignore-certificate-errors')
options.add_argument('--incognito')
# options.add_argument('--headless')
driver = webdriver.Chrome("C:\Program Files (x86)\chromedriver.exe", chrome_options=options)
driver.get('https://coinmarketcap.com/')
time.sleep(5)
html = driver.page_source
soup = BeautifulSoup(html, "html.parser")
tbody = soup.tbody
trs = tbody.contents
for tr in trs:
print(tr)
driver.close()
Now if I have Selenium open Chrome with the headless option turned on, I get the same output I would normally get without having pre-loaded the page. The same thing happens if I'm not in headless mode and I simply let the page load by itself, without scrolling through the content manually.
Does anyone know why this is? Is there a way to get the dynamic content to load without manually scrolling through each time I run the code?
Actually, data is loaded dynamically by javascipt. So you can grab data easily
from api calls json response:
Here is the working example:
Code:
import requests
import json
url= 'https://api.coinmarketcap.com/data-api/v3/cryptocurrency/listing?start=1&limit=100&sortBy=market_cap&sortType=desc&convert=USD,BTC,ETH&cryptoType=all&tagType=all&audited=false&aux=ath,atl,high24h,low24h,num_market_pairs,cmc_rank,date_added,max_supply,circulating_supply,total_supply,volume_7d,volume_30d'
r = requests.get(url)
for item in r.json()['data']['cryptoCurrencyList']:
name = item['name']
print('crypto_name:' + str(name))
Output:
crypto_name:Bitcoin
crypto_name:Ethereum
crypto_name:Binance Coin
crypto_name:Cardano
crypto_name:Tether
crypto_name:Solana
crypto_name:XRP
crypto_name:Polkadot
crypto_name:USD Coin
crypto_name:Dogecoin
crypto_name:Terra
crypto_name:Uniswap
crypto_name:Wrapped Bitcoin
crypto_name:Litecoin
crypto_name:Avalanche
crypto_name:Binance USD
crypto_name:Chainlink
crypto_name:Bitcoin Cash
crypto_name:Algorand
crypto_name:SHIBA INU
crypto_name:Polygon
crypto_name:Stellar
crypto_name:VeChain
crypto_name:Internet Computer
crypto_name:Cosmos
crypto_name:FTX Token
crypto_name:Filecoin
crypto_name:Axie Infinity
crypto_name:Ethereum Classic
crypto_name:TRON
crypto_name:Bitcoin BEP2
crypto_name:Dai
crypto_name:THETA
crypto_name:Tezos
crypto_name:Fantom
crypto_name:Hedera
crypto_name:NEAR Protocol
crypto_name:Elrond
crypto_name:Monero
crypto_name:Crypto.com Coin
crypto_name:PancakeSwap
crypto_name:EOS
crypto_name:The Graph
crypto_name:Flow
crypto_name:Aave
crypto_name:Klaytn
crypto_name:IOTA
crypto_name:eCash
crypto_name:Quant
crypto_name:Bitcoin SV
crypto_name:Neo
crypto_name:Kusama
crypto_name:UNUS SED LEO
crypto_name:Waves
crypto_name:Stacks
crypto_name:TerraUSD
crypto_name:Harmony
crypto_name:Maker
crypto_name:BitTorrent
crypto_name:Celo
crypto_name:Helium
crypto_name:OMG Network
crypto_name:THORChain
crypto_name:Dash
crypto_name:Amp
crypto_name:Zcash
crypto_name:Compound
crypto_name:Chiliz
crypto_name:Arweave
crypto_name:Holo
crypto_name:Decred
crypto_name:NEM
crypto_name:Theta Fuel
crypto_name:Enjin Coin
crypto_name:Revain
crypto_name:Huobi Token
crypto_name:OKB
crypto_name:Decentraland
crypto_name:SushiSwap
crypto_name:ICON
crypto_name:XDC Network
crypto_name:Qtum
crypto_name:TrueUSD
crypto_name:yearn.finance
crypto_name:Nexo
crypto_name:Celsius
crypto_name:Bitcoin Gold
crypto_name:Curve DAO Token
crypto_name:Mina
crypto_name:KuCoin Token
crypto_name:Zilliqa
crypto_name:Perpetual Protocol
crypto_name:Ren
crypto_name:dYdX
crypto_name:Ravencoin
crypto_name:Synthetix
crypto_name:renBTC
crypto_name:Telcoin
crypto_name:Basic Attention Token
crypto_name:Horizenput:

https://www.realestate.com.au/ not permitting web scraping?

I am trying to extract data from https://www.realestate.com.au/
First I create my url based on the type of property that I am looking for and then I open the url using selenium webdriver, but the page is blank!
Any idea why it happens? Is it because this website doesn't provide web scraping permission? Is there any way to scrape this website?
Here is my code:
from selenium import webdriver
from bs4 import BeautifulSoup
import time
PostCode = "2153"
propertyType = "house"
minBedrooms = "3"
maxBedrooms = "4"
page = "1"
url = "https://www.realestate.com.au/sold/property-{p}-with-{mib}-bedrooms-in-{po}/list-{pa}?maxBeds={mab}&includeSurrounding=false".format(p = propertyType, mib = minBedrooms, po = PostCode, pa = page, mab = maxBedrooms)
print(url)
# url should be "https://www.realestate.com.au/sold/property-house-with-3-bedrooms-in-2153/list-1?maxBeds=4&includeSurrounding=false"
driver = webdriver.Edge("./msedgedriver.exe") # edit the address to where your driver is located
driver.get(url)
time.sleep(3)
src = driver.page_source
soup = BeautifulSoup(src, 'html.parser')
print(soup)
you are passing the link incorrectly, try it
driver.get("your link")
api - https://selenium-python.readthedocs.io/api.html?highlight=get#:~:text=ef_driver.get(%22http%3A//www.google.co.in/%22)
I did try to access realestate.com.au through selenium, and in a different use case through scrapy.
I even got the results from scrapy crawling through use of proper user-agent and cookie but after a few days realestate.com.au detects selenium / scrapy and blocks the requests.
Additionally, it it clearly written in their terms & conditions that indexing any content in their website is strictly prohibited.
You can find more information / analysis in these questions:
Chrome browser initiated through ChromeDriver gets detected
selenium isn't loading the page
Bottom line is, you have to surpass their security if you want to scrape the content.

HTML acquired in Python code is not the same as displayed webpage

I have recently started learning web scraping with Scrapy and as a practice, I decided to scrape a weather data table from this url.
By inspecting the table element of the page, I copy its XPath into my code but I only get an empty list when running the code. I tried to check which tables are present in the HTML using this code:
from scrapy import Selector
import requests
import pandas as pd
url = 'https://www.wunderground.com/history/monthly/OIII/date/2000-5'
html = requests.get(url).content
sel = Selector(text=html)
table = sel.xpath('//table')
It only returns one table and it is not the one I wanted.
After some research, I found out that it might have something to do with JavaScript rendering in the page source code and that Python requests can't handle JavaScript.
After going through a number of SO Q&As, I came upon a certain requests-html library which can apparently handle JS execution so I tried acquiring the table using this code snippet:
from requests_html import HTMLSession
from scrapy import Selector
session = HTMLSession()
resp = session.get('https://www.wunderground.com/history/monthly/OIII/date/2000-5')
resp.html.render()
html = resp.html.html
sel = Selector(text=html)
tables = sel.xpath('//table')
print(tables)
But the result doesn't change. How can I acquire that table?
Problem
Multiple problems may be at play here—not only javascript execution, but HTML5 APIs, cookies, user agent, etc.
Solution
Consider using Selenium with headless Chrome or Firefox web driver. Using selenium with a web driver ensures that page will be loaded as intended. Headless mode ensures that you can run your code without spawning the GUI browser—you can, of course, disable headless mode to see what's being done to the page in realtime and even add a breakpoint so that you can debug beyond pdb in the browser's console.
Example Code:
from selenium import webdriver
from selenium.webdriver.chrome.options import Options
chrome_options = Options()
chrome_options.add_argument("--no-sandbox")
chrome_options.add_argument("--headless")
driver = webdriver.Chrome(options=chrome_options)
driver.get("https://www.wunderground.com/history/monthly/OIII/date/2000-5")
tables = driver.find_elements_by_xpath('//table') # There are several APIs to locate elements available.
print(tables)
References
Selenium Github: https://github.com/SeleniumHQ/selenium
Selenium (Python) Documentation: https://selenium-python.readthedocs.io/getting-started.html
Locating Elements: https://selenium-python.readthedocs.io/locating-elements.html
you can use scrapy-splash plugin to work scrapy with Splash (scrapinghub's javascript browser)
Using splash you can render javascript and also execute user events like mouse click

use scrapy to crawl node

I'm trying to use scrapy to crawl some advertise information from this web sites.
That website has some div tag with class="product-card new_ outofstock installments_ ".
When I use:
items = response.xpath("//div[contains(#class, 'product-')]")
I get some node with class attribute = "product-description" but not "product-card".
When I use:
items = response.xpath("//div[contains(#class, 'product-card')]")
I still get nothing in result.
Why is that ?
As pointed in the previous answer, the content you are trying to scrape is generated dynamically using javascript. If performance is not a big deal for you, then you can use Selenium to emulate a real user and interact with the site. At the same time you can let Scrapy get the data for you.
If you want a similar example of how to do this, consider this tutorial: http://www.6020peaks.com/2014/12/how-to-scrape-hidden-web-data-with-python/
The data you want is being populated by javascripts.
You would have to use a selenium webdriver to extract the data.
If you want to check before hand if data is being populated using javascript, open a scrapy shell and try extracting the data as below.
scrapy shell 'http://www.lazada.vn/dien-thoai-may-tinh-bang/?ref=MT'
>>>response.xpath('//div[contains(#class,"product-card")]')
Output:
[]
Now, if you use the same Xpath in the browser and get a result as below:
Then the data is populated using scripts and selenium would have to be used to get data.
Here is an example to extract data using selenium:
import scrapy
from selenium import webdriver
from scrapy.http import TextResponse
class ProductSpider(scrapy.Spider):
name = "product_spider"
allowed_domains = ['lazada.vn']
start_urls = ['http://www.lazada.vn/dien-thoai-may-tinh-bang/?ref=MT']
def __init__(self):
self.driver = webdriver.Firefox()
def parse(self, response):
self.driver.get(response.url)
page = TextResponse(response.url, body=self.driver.page_source, encoding='utf-8')
required_data = page.xpath('//div[contains(#class,"product-card")]').extract()
self.driver.close()
Here are some examples of "selenium spiders":
Executing Javascript Submit form functions using scrapy in python
Snipplr
Scrapy with selenium
Extract data from dynamic webpages

Submit form that renders dynamically with Scrapy?

I'm trying to submit a dynamically generated user login form using Scrapy and then parse the HTML on the page that corresponds to a successful login.
I was wondering how I could do that with Scrapy or a combination of Scrapy and Selenium. Selenium makes it possible to find the element on the DOM, but I was wondering if it would be possible to "give control back" to Scrapy after getting the full HTML in order to allow it to carry out the form submission and save the necessary cookies, session data etc. in order to scrape the page.
Basically, the only reason I thought Selenium was necessary was because I needed the page to render from the Javascript before Scrapy looks for the <form> element. Are there any alternatives to this, however?
Thank you!
Edit: This question is similar to this one, but unfortunately the accepted answer deals with the Requests library instead of Selenium or Scrapy. Though that scenario may be possible in some cases (watch this to learn more), as alecxe points out, Selenium may be required if "parts of the page [such as forms] are loaded via API calls and inserted into the page with the help of javascript code being executed in the browser".
Scrapy is not actually a great fit for coursera site since it is extremely asynchronous. Parts of the page are loaded via API calls and inserted into the page with a help of javascript code being executed in the browser. Scrapy is not a browser and cannot handle it.
Which raises the point - why not use the publicly available Coursera API?
Aside from what is documented, there are other endpoints that you can see called in browser developer tools - you need to be authenticated to be able to use them. For example, if you are logged in, you can see the list of courses you've taken:
There is a call to memberships.v1 endpoint.
For the sake of an example, let's start selenium, log in and grab the cookies with get_cookies(). Then, let's yield a Request to memberships.v1 endpoint to get the list of archived courses providing the cookies we've got from selenium:
import json
import scrapy
from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC
LOGIN = 'email'
PASSWORD = 'password'
class CourseraSpider(scrapy.Spider):
name = "courseraSpider"
allowed_domains = ["coursera.org"]
def start_requests(self):
self.driver = webdriver.Chrome()
self.driver.maximize_window()
self.driver.get('https://www.coursera.org/login')
form = WebDriverWait(self.driver, 10).until(EC.presence_of_element_located((By.XPATH, "//div[#data-js='login-body']//div[#data-js='facebook-button-divider']/following-sibling::form")))
email = WebDriverWait(form, 10).until(EC.visibility_of_element_located((By.ID, 'user-modal-email')))
email.send_keys(LOGIN)
password = form.find_element_by_name('password')
password.send_keys(PASSWORD)
login = form.find_element_by_xpath('//button[. = "Log In"]')
login.click()
WebDriverWait(self.driver, 20).until(EC.visibility_of_element_located((By.XPATH, "//h2[. = 'My Courses']")))
self.driver.get('https://www.coursera.org/')
cookies = self.driver.get_cookies()
self.driver.close()
courses_url = 'https://www.coursera.org/api/memberships.v1'
params = {
'fields': 'courseId,enrolledTimestamp,grade,id,lastAccessedTimestamp,role,v1SessionId,vc,vcMembershipId,courses.v1(display,partnerIds,photoUrl,specializations,startDate,v1Details),partners.v1(homeLink,name),v1Details.v1(sessionIds),v1Sessions.v1(active,dbEndDate,durationString,hasSigTrack,startDay,startMonth,startYear),specializations.v1(logo,name,partnerIds,shortName)&includes=courseId,vcMembershipId,courses.v1(partnerIds,specializations,v1Details),v1Details.v1(sessionIds),specializations.v1(partnerIds)',
'q': 'me',
'showHidden': 'false',
'filter': 'archived'
}
params = '&'.join(key + '=' + value for key, value in params.iteritems())
yield scrapy.Request(courses_url + '?' + params, cookies=cookies)
def parse(self, response):
data = json.loads(response.body)
for course in data['linked']['courses.v1']:
print course['name']
For me, it prints:
Algorithms, Part I
Computing for Data Analysis
Pattern-Oriented Software Architectures for Concurrent and Networked Software
Computer Networks
Which proves that we can give Scrapy the cookies from selenium and successfully extract the data from the "for logged in users only" pages.
Additionally, make sure you don't violate the rules from the Terms of Use, specifically:
In addition, as a condition of accessing the Sites, you agree not to
... (c) use any high-volume, automated or electronic means to access
the Sites (including without limitation, robots, spiders, scripts or
web-scraping tools);

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