from abc import ABC, abstractmethod import chardet import os from selenium import webdriver from selenium.webdriver.common.desired_capabilities import DesiredCapabilities from selenium.webdriver.common.proxy import Proxy as SeleniumProxy from selenium.common.exceptions import WebDriverException import requests import time import urllib3.exceptions 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 fetcher_description ="No description" @abstractmethod def get_error(self): return self.error @abstractmethod def run(self, url, timeout, request_headers, request_body, request_method): # Should set self.error, self.status_code and self.content pass @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) # # Returns tuple(mime_type, stream) # @abstractmethod # def return_diff(self, stream_a, stream_b): # return def available_fetchers(): import inspect from changedetectionio import content_fetcher p=[] for name, obj in inspect.getmembers(content_fetcher): 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 "html_" in name: t=tuple([name,obj.fetcher_description]) p.append(t) return p class 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): # .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('"') if proxy_args: self.proxy = SeleniumProxy(raw=proxy_args) def run(self, url, timeout, request_headers, request_body, request_method): # request_body, request_method unused for now, until some magic in the future happens. # check env for WEBDRIVER_URL driver = webdriver.Remote( command_executor=self.command_executor, desired_capabilities=DesiredCapabilities.CHROME, proxy=self.proxy) try: driver.get(url) except WebDriverException as e: # Be sure we close the session window driver.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 = driver.page_source self.headers = {} driver.quit() def is_ready(self): from selenium import webdriver from selenium.webdriver.common.desired_capabilities import DesiredCapabilities from selenium.common.exceptions import WebDriverException driver = webdriver.Remote( command_executor=self.command_executor, desired_capabilities=DesiredCapabilities.CHROME) # driver.quit() seems to cause better exceptions driver.quit() return True # "html_requests" is listed as the default fetcher in store.py! class html_requests(Fetcher): fetcher_description = "Basic fast Plaintext/HTTP Client" def run(self, url, timeout, request_headers, request_body, request_method): r = requests.request(method=request_method, data=request_body, url=url, headers=request_headers, timeout=timeout, 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 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