whitew1994ww/scrapy-headless

Scrapy with Headless Selenium, for scraping interactive web pages

Scrapy with Headless Selenium

Scrapy middleware to handle dynamic web pages, using Selenium and running in headless mode by default:

1. Running in headless mode by default
2. Running by default with ad blocking browser plugin, for faster scraping (only for FireFox, see this issue)
3. Dynamic responses, to allow interaction with the web page being scraped

Installation

$ pip install scrapy-headless-selenium

You should use python>=3.6. You will also need one of the Selenium compatible browsers and drivers (FireFox & geckodriver or Chrome & chromium-driver).

Configuration

1. Add the browser to use, the path to the driver executable, and the arguments to pass to the executable to the scrapy settings:

   from shutil import which
   
   SELENIUM_DRIVER_NAME = 'firefox'
   SELENIUM_DRIVER_EXECUTABLE_PATH = which('geckodriver')
   SELENIUM_DRIVER_ARGUMENTS = ['-headless']  # '--headless' if using chrome instead of firefox

Optionally, set the path to the browser executable: python SELENIUM_BROWSER_EXECUTABLE_PATH = which('firefox')

2. Add the SeleniumMiddleware to the downloader middlewares and to the spider middlewares:

   DOWNLOADER_MIDDLEWARES = {
       'scrapy_headless.SeleniumMiddleware': 800
   }
   SPIDER_MIDDLEWARES = {
       'scrapy_headless.SeleniumMiddleware': 800
   }

Usage

Use the scrapy_headless.SeleniumRequest instead of the scrapy built-in Request like below:

from scrapy_headless import SeleniumRequest

yield SeleniumRequest(url, self.parse_result)

The request will be handled by selenium, and the request will have an additional meta key, named driver containing the selenium driver with the request processed.

def parse_result(self, response):
    print(response.request.meta['driver'].title)

For more information about the available driver methods and attributes, refer to the selenium python documentation

The selector response attribute work as usual (but contains the html processed by the selenium driver).

def parse_result(self, response):
    print(response.selector.xpath('//title/@text'))

The Selenium WebDriver is also exposed through the response.interact property, to allow interaction with the browser. The response also implements a click method which excepts a CSS / XPATH selector, to click on an element and return a new response with the new body:

def parse_result(self, response):
    response = response.click('#id')  # equivalent to response.click('//[@id="id"]')
    print(response.selector.xpath('//title/@text'))  # searches the reloaded response body

Additional arguments

The scrapy_headless.SeleniumRequest accept 4 additional arguments:

wait_time / wait_until

When used, selenium will perform an Explicit wait before returning the response to the spider.

from selenium.webdriver.common.by import By
from selenium.webdriver.support import expected_conditions as EC

yield SeleniumRequest(
    url=url,
    callback=self.parse_result,
    wait_time=10,
    wait_until=EC.element_to_be_clickable((By.ID, 'someid'))
)

screenshot

When used, selenium will take a screenshot of the page and the binary data of the .png captured will be added to the response meta:

yield SeleniumRequest(
    url=url,
    callback=self.parse_result,
    screenshot=True
)

def parse_result(self, response):
    with open('image.png', 'wb') as image_file:
        image_file.write(response.meta['screenshot'])

script

When used, selenium will execute custom JavaScript code.

yield SeleniumRequest(
    url,
    self.parse_result,
    script='window.scrollTo(0, document.body.scrollHeight);',
)

Thanks

Special thanks to @clemfromspace which wrote scrapy-selenium, which is the original fork for this project.