import os import threading import queue import time from changedetectionio import content_fetcher from changedetectionio.fetch_site_status import FilterNotFoundInResponse # A single update worker # # Requests for checking on a single site(watch) from a queue of watches # (another process inserts watches into the queue that are time-ready for checking) import logging import sys class update_worker(threading.Thread): current_uuid = None def __init__(self, q, notification_q, app, datastore, *args, **kwargs): logging.basicConfig(stream=sys.stderr, level=logging.DEBUG) self.q = q self.app = app self.notification_q = notification_q self.datastore = datastore super().__init__(*args, **kwargs) def send_content_changed_notification(self, t, watch_uuid): from changedetectionio import diff from changedetectionio.notification import ( default_notification_format_for_watch ) n_object = {} watch = self.datastore.data['watching'].get(watch_uuid, False) if not watch: return watch_history = watch.history dates = list(watch_history.keys()) # Theoretically it's possible that this could be just 1 long, # - In the case that the timestamp key was not unique if len(dates) == 1: raise ValueError( "History index had 2 or more, but only 1 date loaded, timestamps were not unique? maybe two of the same timestamps got written, needs more delay?" ) n_object['notification_urls'] = watch['notification_urls'] if len(watch['notification_urls']) else \ self.datastore.data['settings']['application']['notification_urls'] n_object['notification_title'] = watch['notification_title'] if watch['notification_title'] else \ self.datastore.data['settings']['application']['notification_title'] n_object['notification_body'] = watch['notification_body'] if watch['notification_body'] else \ self.datastore.data['settings']['application']['notification_body'] n_object['notification_format'] = watch['notification_format'] if watch['notification_format'] != default_notification_format_for_watch else \ self.datastore.data['settings']['application']['notification_format'] # Only prepare to notify if the rules above matched if 'notification_urls' in n_object and n_object['notification_urls']: # HTML needs linebreak, but MarkDown and Text can use a linefeed if n_object['notification_format'] == 'HTML': line_feed_sep = "
" else: line_feed_sep = "\n" with open(watch_history[dates[-1]], 'rb') as f: snapshot_contents = f.read() n_object.update({ 'watch_url': watch['url'], 'uuid': watch_uuid, 'screenshot': watch.get_screenshot() if watch.get('notification_screenshot') else False, 'current_snapshot': snapshot_contents.decode('utf-8'), 'diff': diff.render_diff(watch_history[dates[-2]], watch_history[dates[-1]], line_feed_sep=line_feed_sep), 'diff_full': diff.render_diff(watch_history[dates[-2]], watch_history[dates[-1]], True, line_feed_sep=line_feed_sep) }) logging.info (">> SENDING NOTIFICATION") self.notification_q.put(n_object) else: logging.info (">> NO Notification sent, notification_url was empty in both watch and system") def send_filter_failure_notification(self, watch_uuid): threshold = self.datastore.data['settings']['application'].get('filter_failure_notification_threshold_attempts') watch = self.datastore.data['watching'].get(watch_uuid, False) if not watch: return n_object = {'notification_title': 'Changedetection.io - Alert - CSS/xPath filter was not present in the page', 'notification_body': "Your configured CSS/xPath filters of '{}' for {{watch_url}} did not appear on the page after {} attempts, did the page change layout?\n\nLink: {{base_url}}/edit/{{watch_uuid}}\n\nThanks - Your omniscient changedetection.io installation :)\n".format( ", ".join(watch['include_filters']), threshold), 'notification_format': 'text'} if len(watch['notification_urls']): n_object['notification_urls'] = watch['notification_urls'] elif len(self.datastore.data['settings']['application']['notification_urls']): n_object['notification_urls'] = self.datastore.data['settings']['application']['notification_urls'] # Only prepare to notify if the rules above matched if 'notification_urls' in n_object: n_object.update({ 'watch_url': watch['url'], 'uuid': watch_uuid, 'screenshot': False }) self.notification_q.put(n_object) print("Sent filter not found notification for {}".format(watch_uuid)) def cleanup_error_artifacts(self, uuid): # All went fine, remove error artifacts cleanup_files = ["last-error-screenshot.png", "last-error.txt"] for f in cleanup_files: full_path = os.path.join(self.datastore.datastore_path, uuid, f) if os.path.isfile(full_path): os.unlink(full_path) def run(self): from changedetectionio import fetch_site_status update_handler = fetch_site_status.perform_site_check(datastore=self.datastore) while not self.app.config.exit.is_set(): try: priority, uuid = self.q.get(block=False) except queue.Empty: pass else: self.current_uuid = uuid if uuid in list(self.datastore.data['watching'].keys()): changed_detected = False contents = b'' screenshot = False update_obj= {} xpath_data = False process_changedetection_results = True print("> Processing UUID {} Priority {} URL {}".format(uuid, priority, self.datastore.data['watching'][uuid]['url'])) now = time.time() try: changed_detected, update_obj, contents = update_handler.run(uuid) # Re #342 # In Python 3, all strings are sequences of Unicode characters. There is a bytes type that holds raw bytes. # We then convert/.decode('utf-8') for the notification etc if not isinstance(contents, (bytes, bytearray)): raise Exception("Error - returned data from the fetch handler SHOULD be bytes") except PermissionError as e: self.app.logger.error("File permission error updating", uuid, str(e)) process_changedetection_results = False except content_fetcher.ReplyWithContentButNoText as e: # Totally fine, it's by choice - just continue on, nothing more to care about # Page had elements/content but no renderable text # Backend (not filters) gave zero output self.datastore.update_watch(uuid=uuid, update_obj={'last_error': "Got HTML content but no text found (With {} reply code).".format(e.status_code)}) if e.screenshot: self.datastore.save_screenshot(watch_uuid=uuid, screenshot=e.screenshot) process_changedetection_results = False except content_fetcher.Non200ErrorCodeReceived as e: if e.status_code == 403: err_text = "Error - 403 (Access denied) received" elif e.status_code == 404: err_text = "Error - 404 (Page not found) received" elif e.status_code == 500: err_text = "Error - 500 (Internal server Error) received" else: err_text = "Error - Request returned a HTTP error code {}".format(str(e.status_code)) if e.screenshot: self.datastore.save_screenshot(watch_uuid=uuid, screenshot=e.screenshot, as_error=True) if e.xpath_data: self.datastore.save_xpath_data(watch_uuid=uuid, data=e.xpath_data, as_error=True) if e.page_text: self.datastore.save_error_text(watch_uuid=uuid, contents=e.page_text) self.datastore.update_watch(uuid=uuid, update_obj={'last_error': err_text, # So that we get a trigger when the content is added again 'previous_md5': ''}) process_changedetection_results = False except FilterNotFoundInResponse as e: if not self.datastore.data['watching'].get(uuid): continue err_text = "Warning, no filters were found, no change detection ran." self.datastore.update_watch(uuid=uuid, update_obj={'last_error': err_text, # So that we get a trigger when the content is added again 'previous_md5': ''}) # Only when enabled, send the notification if self.datastore.data['watching'][uuid].get('filter_failure_notification_send', False): c = self.datastore.data['watching'][uuid].get('consecutive_filter_failures', 5) c += 1 # Send notification if we reached the threshold? threshold = self.datastore.data['settings']['application'].get('filter_failure_notification_threshold_attempts', 0) print("Filter for {} not found, consecutive_filter_failures: {}".format(uuid, c)) if threshold > 0 and c >= threshold: if not self.datastore.data['watching'][uuid].get('notification_muted'): self.send_filter_failure_notification(uuid) c = 0 self.datastore.update_watch(uuid=uuid, update_obj={'consecutive_filter_failures': c}) process_changedetection_results = True except content_fetcher.EmptyReply as e: # Some kind of custom to-str handler in the exception handler that does this? err_text = "EmptyReply - try increasing 'Wait seconds before extracting text', Status Code {}".format(e.status_code) self.datastore.update_watch(uuid=uuid, update_obj={'last_error': err_text, 'last_check_status': e.status_code}) except content_fetcher.ScreenshotUnavailable as e: err_text = "Screenshot unavailable, page did not render fully in the expected time - try increasing 'Wait seconds before extracting text'" self.datastore.update_watch(uuid=uuid, update_obj={'last_error': err_text, 'last_check_status': e.status_code}) process_changedetection_results = False except content_fetcher.JSActionExceptions as e: err_text = "Error running JS Actions - Page request - "+e.message if e.screenshot: self.datastore.save_screenshot(watch_uuid=uuid, screenshot=e.screenshot, as_error=True) self.datastore.update_watch(uuid=uuid, update_obj={'last_error': err_text, 'last_check_status': e.status_code}) except content_fetcher.PageUnloadable as e: err_text = "Page request from server didnt respond correctly" if e.message: err_text = "{} - {}".format(err_text, e.message) if e.screenshot: self.datastore.save_screenshot(watch_uuid=uuid, screenshot=e.screenshot, as_error=True) self.datastore.update_watch(uuid=uuid, update_obj={'last_error': err_text, 'last_check_status': e.status_code}) except Exception as e: self.app.logger.error("Exception reached processing watch UUID: %s - %s", uuid, str(e)) self.datastore.update_watch(uuid=uuid, update_obj={'last_error': str(e)}) # Other serious error process_changedetection_results = False else: # Crash protection, the watch entry could have been removed by this point (during a slow chrome fetch etc) if not self.datastore.data['watching'].get(uuid): continue # Mark that we never had any failures if not self.datastore.data['watching'][uuid].get('ignore_status_codes'): update_obj['consecutive_filter_failures'] = 0 self.cleanup_error_artifacts(uuid) # Different exceptions mean that we may or may not want to bump the snapshot, trigger notifications etc if process_changedetection_results: try: watch = self.datastore.data['watching'][uuid] fname = "" # Saved history text filename # For the FIRST time we check a site, or a change detected, save the snapshot. if changed_detected or not watch['last_checked']: # A change was detected watch.save_history_text(contents=contents, timestamp=str(round(time.time()))) self.datastore.update_watch(uuid=uuid, update_obj=update_obj) # A change was detected if changed_detected: print (">> Change detected in UUID {} - {}".format(uuid, watch['url'])) # Notifications should only trigger on the second time (first time, we gather the initial snapshot) if watch.history_n >= 2: if not self.datastore.data['watching'][uuid].get('notification_muted'): self.send_content_changed_notification(self, watch_uuid=uuid) except Exception as e: # Catch everything possible here, so that if a worker crashes, we don't lose it until restart! print("!!!! Exception in update_worker !!!\n", e) self.app.logger.error("Exception reached processing watch UUID: %s - %s", uuid, str(e)) self.datastore.update_watch(uuid=uuid, update_obj={'last_error': str(e)}) if self.datastore.data['watching'].get(uuid): # Always record that we atleast tried count = self.datastore.data['watching'][uuid].get('check_count', 0) + 1 self.datastore.update_watch(uuid=uuid, update_obj={'fetch_time': round(time.time() - now, 3), 'last_checked': round(time.time()), 'check_count': count }) # Always save the screenshot if it's available if update_handler.screenshot: self.datastore.save_screenshot(watch_uuid=uuid, screenshot=update_handler.screenshot) if update_handler.xpath_data: self.datastore.save_xpath_data(watch_uuid=uuid, data=update_handler.xpath_data) self.current_uuid = None # Done self.q.task_done() # Give the CPU time to interrupt time.sleep(0.1) self.app.config.exit.wait(1)