from abc import ABC, abstractmethod import chardet import os import requests import time import urllib3.exceptions import sys class EmptyReply(Exception): def __init__(self, status_code, url): # Set this so we can use it in other parts of the app self.status_code = status_code self.url = url return pass class Fetcher(): error = None status_code = None content = None headers = None # Will be needed in the future by the VisualSelector, always get this where possible. screenshot = False fetcher_description = "No description" system_http_proxy = os.getenv('HTTP_PROXY') system_https_proxy = os.getenv('HTTPS_PROXY') @abstractmethod def get_error(self): return self.error @abstractmethod def run(self, url, timeout, request_headers, request_body, request_method, ignore_status_codes=False): # Should set self.error, self.status_code and self.content pass @abstractmethod def quit(self): return @abstractmethod def get_last_status_code(self): return self.status_code @abstractmethod # Return true/false if this checker is ready to run, in the case it needs todo some special config check etc def is_ready(self): return True # Maybe for the future, each fetcher provides its own diff output, could be used for text, image # the current one would return javascript output (as we use JS to generate the diff) # def available_fetchers(): # See the if statement at the bottom of this file for how we switch between playwright and webdriver import inspect p = [] for name, obj in inspect.getmembers(sys.modules[__name__], inspect.isclass): if inspect.isclass(obj): # @todo html_ is maybe better as fetcher_ or something # In this case, make sure to edit the default one in store.py and fetch_site_status.py if name.startswith('html_'): t = tuple([name, obj.fetcher_description]) p.append(t) return p class base_html_playwright(Fetcher): fetcher_description = "Playwright {}/Javascript".format( os.getenv("PLAYWRIGHT_BROWSER_TYPE", 'chromium').capitalize() ) if os.getenv("PLAYWRIGHT_DRIVER_URL"): fetcher_description += " via '{}'".format(os.getenv("PLAYWRIGHT_DRIVER_URL")) browser_type = '' command_executor = '' # Configs for Proxy setup # In the ENV vars, is prefixed with "playwright_proxy_", so it is for example "playwright_proxy_server" playwright_proxy_settings_mappings = ['bypass', 'server', 'username', 'password'] proxy = None def __init__(self, proxy_override=None): # .strip('"') is going to save someone a lot of time when they accidently wrap the env value self.browser_type = os.getenv("PLAYWRIGHT_BROWSER_TYPE", 'chromium').strip('"') self.command_executor = os.getenv( "PLAYWRIGHT_DRIVER_URL", 'ws://playwright-chrome:3000/playwright' ).strip('"') # If any proxy settings are enabled, then we should setup the proxy object proxy_args = {} for k in self.playwright_proxy_settings_mappings: v = os.getenv('playwright_proxy_' + k, False) if v: proxy_args[k] = v.strip('"') if proxy_args: self.proxy = proxy_args # allow per-watch proxy selection override if proxy_override: self.proxy = {'server': proxy_override} def run(self, url, timeout, request_headers, request_body, request_method, ignore_status_codes=False): from playwright.sync_api import sync_playwright import playwright._impl._api_types from playwright._impl._api_types import Error, TimeoutError with sync_playwright() as p: browser_type = getattr(p, self.browser_type) # Seemed to cause a connection Exception even tho I can see it connect # self.browser = browser_type.connect(self.command_executor, timeout=timeout*1000) browser = browser_type.connect_over_cdp(self.command_executor, timeout=timeout * 1000) # Set user agent to prevent Cloudflare from blocking the browser # Use the default one configured in the App.py model that's passed from fetch_site_status.py context = browser.new_context( user_agent=request_headers['User-Agent'] if request_headers.get('User-Agent') else 'Mozilla/5.0', proxy=self.proxy ) page = context.new_page() page.set_viewport_size({"width": 1280, "height": 1024}) try: response = page.goto(url, timeout=timeout * 1000, wait_until='commit') # Wait_until = commit # - `'commit'` - consider operation to be finished when network response is received and the document started loading. # Better to not use any smarts from Playwright and just wait an arbitrary number of seconds # This seemed to solve nearly all 'TimeoutErrors' extra_wait = int(os.getenv("WEBDRIVER_DELAY_BEFORE_CONTENT_READY", 5)) page.wait_for_timeout(extra_wait * 1000) except playwright._impl._api_types.TimeoutError as e: raise EmptyReply(url=url, status_code=None) if response is None: raise EmptyReply(url=url, status_code=None) self.status_code = response.status self.content = page.content() self.headers = response.all_headers() # Some bug where it gives the wrong screenshot size, but making a request with the clip set first seems to solve it # JPEG is better here because the screenshots can be very very large page.screenshot(type='jpeg', clip={'x': 1.0, 'y': 1.0, 'width': 1280, 'height': 1024}) self.screenshot = page.screenshot(type='jpeg', full_page=True, quality=90) context.close() browser.close() class base_html_webdriver(Fetcher): if os.getenv("WEBDRIVER_URL"): fetcher_description = "WebDriver Chrome/Javascript via '{}'".format(os.getenv("WEBDRIVER_URL")) else: fetcher_description = "WebDriver Chrome/Javascript" command_executor = '' # Configs for Proxy setup # In the ENV vars, is prefixed with "webdriver_", so it is for example "webdriver_sslProxy" selenium_proxy_settings_mappings = ['proxyType', 'ftpProxy', 'httpProxy', 'noProxy', 'proxyAutoconfigUrl', 'sslProxy', 'autodetect', 'socksProxy', 'socksVersion', 'socksUsername', 'socksPassword'] proxy = None def __init__(self, proxy_override=None): from selenium.webdriver.common.proxy import Proxy as SeleniumProxy # .strip('"') is going to save someone a lot of time when they accidently wrap the env value self.command_executor = os.getenv("WEBDRIVER_URL", 'http://browser-chrome:4444/wd/hub').strip('"') # If any proxy settings are enabled, then we should setup the proxy object proxy_args = {} for k in self.selenium_proxy_settings_mappings: v = os.getenv('webdriver_' + k, False) if v: proxy_args[k] = v.strip('"') # Map back standard HTTP_ and HTTPS_PROXY to webDriver httpProxy/sslProxy if not proxy_args.get('webdriver_httpProxy') and self.system_http_proxy: proxy_args['httpProxy'] = self.system_http_proxy if not proxy_args.get('webdriver_sslProxy') and self.system_https_proxy: proxy_args['httpsProxy'] = self.system_https_proxy # Allows override the proxy on a per-request basis if proxy_override is not None: proxy_args['httpProxy'] = proxy_override if proxy_args: self.proxy = SeleniumProxy(raw=proxy_args) def run(self, url, timeout, request_headers, request_body, request_method, ignore_status_codes=False): from selenium import webdriver from selenium.webdriver.common.desired_capabilities import DesiredCapabilities from selenium.common.exceptions import WebDriverException # request_body, request_method unused for now, until some magic in the future happens. # check env for WEBDRIVER_URL self.driver = webdriver.Remote( command_executor=self.command_executor, desired_capabilities=DesiredCapabilities.CHROME, proxy=self.proxy) try: self.driver.get(url) except WebDriverException as e: # Be sure we close the session window self.quit() raise # @todo - how to check this? is it possible? self.status_code = 200 # @todo somehow we should try to get this working for WebDriver # raise EmptyReply(url=url, status_code=r.status_code) # @todo - dom wait loaded? time.sleep(int(os.getenv("WEBDRIVER_DELAY_BEFORE_CONTENT_READY", 5))) self.content = self.driver.page_source self.headers = {} self.screenshot = self.driver.get_screenshot_as_png() self.quit() # Does the connection to the webdriver work? run a test connection. def is_ready(self): from selenium import webdriver from selenium.webdriver.common.desired_capabilities import DesiredCapabilities from selenium.common.exceptions import WebDriverException self.driver = webdriver.Remote( command_executor=self.command_executor, desired_capabilities=DesiredCapabilities.CHROME) # driver.quit() seems to cause better exceptions self.quit() return True def quit(self): if self.driver: try: self.driver.quit() except Exception as e: print("Exception in chrome shutdown/quit" + str(e)) # "html_requests" is listed as the default fetcher in store.py! class html_requests(Fetcher): fetcher_description = "Basic fast Plaintext/HTTP Client" def __init__(self, proxy_override=None): self.proxy_override = proxy_override def run(self, url, timeout, request_headers, request_body, request_method, ignore_status_codes=False): proxies={} # Allows override the proxy on a per-request basis if self.proxy_override: proxies = {'http': self.proxy_override, 'https': self.proxy_override, 'ftp': self.proxy_override} else: if self.system_http_proxy: proxies['http'] = self.system_http_proxy if self.system_https_proxy: proxies['https'] = self.system_https_proxy r = requests.request(method=request_method, data=request_body, url=url, headers=request_headers, timeout=timeout, proxies=proxies, verify=False) # If the response did not tell us what encoding format to expect, Then use chardet to override what `requests` thinks. # For example - some sites don't tell us it's utf-8, but return utf-8 content # This seems to not occur when using webdriver/selenium, it seems to detect the text encoding more reliably. # https://github.com/psf/requests/issues/1604 good info about requests encoding detection if not r.headers.get('content-type') or not 'charset=' in r.headers.get('content-type'): encoding = chardet.detect(r.content)['encoding'] if encoding: r.encoding = encoding # @todo test this # @todo maybe you really want to test zero-byte return pages? if (not ignore_status_codes and not r) or not r.content or not len(r.content): raise EmptyReply(url=url, status_code=r.status_code) self.status_code = r.status_code self.content = r.text self.headers = r.headers # Decide which is the 'real' HTML webdriver, this is more a system wide config # rather than site-specific. use_playwright_as_chrome_fetcher = os.getenv('PLAYWRIGHT_DRIVER_URL', False) if use_playwright_as_chrome_fetcher: html_webdriver = base_html_playwright else: html_webdriver = base_html_webdriver