From 5572851eca3b2f1bc56aed7232284acc436d2f49 Mon Sep 17 00:00:00 2001 From: François Schmidts Date: Sun, 1 Mar 2015 03:20:12 +0100 Subject: new crawler with cache control and error handling --- pyaggr3g470r/lib/crawler.py | 204 ++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 196 insertions(+), 8 deletions(-) (limited to 'pyaggr3g470r/lib/crawler.py') diff --git a/pyaggr3g470r/lib/crawler.py b/pyaggr3g470r/lib/crawler.py index 1d7fca71..6697e4c3 100644 --- a/pyaggr3g470r/lib/crawler.py +++ b/pyaggr3g470r/lib/crawler.py @@ -1,11 +1,199 @@ +import conf +import json +import logging +import requests import feedparser -import dateutil.parser.parse +import dateutil.parser +from datetime import datetime +from concurrent.futures import ThreadPoolExecutor +from requests_futures.sessions import FuturesSession +from pyaggr3g470r.lib.utils import default_handler +logger = logging.getLogger(__name__) -def get_feed_content(feed): - etag = feed.get('etag', None) - last_modified = None - if feed.get('last_modified'): - last_modified = dateutil.parser.parse(feed['last_modified'])\ - .strftime('%a, %d %b %Y %H:%M:%S %Z') - return feedparser.parse(feed['link'], etag=etag, modified=last_modified) + +def extract_id(entry, keys=[('link', 'link'), + ('published', 'retrieved_date'), + ('updated', 'retrieved_date')], force_id=False): + entry_id = entry.get('entry_id') or entry.get('id') + if entry_id: + return {'entry_id': entry_id} + if not entry_id and force_id: + entry_id = hash("".join(entry[entry_key] for _, entry_key in keys + if entry_key in entry)) + else: + ids = {} + for entry_key, pyagg_key in keys: + if entry_key in entry and pyagg_key not in ids: + ids[pyagg_key] = entry[entry_key] + if 'date' in pyagg_key: + ids[pyagg_key] = dateutil.parser.parse(ids[pyagg_key])\ + .isoformat() + return ids + + +class AbstractCrawler: + __session__ = None + + def __init__(self, auth): + self.auth = auth + self.session = self.get_session() + self.url = conf.PLATFORM_URL + + @classmethod + def get_session(cls): + if cls.__session__ is None: + cls.__session__ = FuturesSession( + executor=ThreadPoolExecutor(max_workers=conf.NB_WORKER)) + cls.__session__.verify = False + return cls.__session__ + + def query_pyagg(self, method, urn, data=None): + if data is None: + data = {} + method = getattr(self.session, method) + return method("%sapi/v1.0/%s" % (self.url, urn), + auth=self.auth, data=json.dumps(data, + default=default_handler), + headers={'Content-Type': 'application/json'}) + + +class PyAggUpdater(AbstractCrawler): + + def __init__(self, feed, entries, headers, auth): + self.feed = feed + self.entries = entries + self.headers = headers + super(PyAggUpdater, self).__init__(auth) + + def to_article(self, entry): + date = datetime.now() + + for date_key in ('published', 'updated'): + if entry.get(date_key): + try: + date = dateutil.parser.parse(entry[date_key]) + except Exception: + pass + else: + break + content = '' + if entry.get('content'): + content = entry['content'][0]['value'] + elif entry.get('summary'): + content = entry['summary'] + + return {'feed_id': self.feed['id'], + 'entry_id': extract_id(entry).get('entry_id', None), + 'link': entry.get('link', self.feed['site_link']), + 'title': entry.get('title', 'No title'), + 'readed': False, 'like': False, + 'content': content, + 'retrieved_date': date.isoformat(), + 'date': date.isoformat()} + + def callback(self, response): + try: + results = response.result().json() + except Exception: + logger.exception('something went wront with feed %r %r %r %r', + self.feed, self.headers, response.result(), + getattr(response.result(), 'data', None)) + return + logger.debug('%r %r - %d entries were not matched', + self.feed['id'], self.feed['title'], len(results)) + for id_to_create in results: + entry = self.entries[tuple(sorted(id_to_create.items()))] + try: + logger.debug('creating %r - %r', entry['title'], id_to_create) + self.to_article(entry) + except: + logger.exception('%r %r %r something failed when parsing %r', + self.feed['title'], self.feed['id'], + self.feed['link'], entry) + self.query_pyagg('post', 'article', self.to_article(entry)) + + now = datetime.now() + logger.debug('%r %r - updating feed etag %r last_mod %r', + self.feed['id'], self.feed['title'], + self.headers.get('etag'), now) + + self.query_pyagg('put', 'feed/%d' % self.feed['id'], {'error_count': 0, + 'etag': self.headers.get('etag', ''), + 'last_modified': self.headers.get('last-modified', '')}) + + +class FeedCrawler(AbstractCrawler): + + def __init__(self, feed, auth): + self.feed = feed + super(FeedCrawler, self).__init__(auth) + + def callback(self, response): + try: + response = response.result() + response.raise_for_status() + except Exception as error: + error_count = self.feed['error_count'] + 1 + logger.warn('%r %r - an error occured while fetching feed; bumping' + ' error count to %r', self.feed['title'], + self.feed['id'], error_count) + self.query_pyagg('put', 'feed/%d' % self.feed['id'], + {'error_count': error_count, + 'last_error': str(error)}) + return + + if response.status_code == 304: + logger.debug("%r %r - feed responded with 304", + self.feed['id'], self.feed['title']) + return + if self.feed['etag'] and response.headers.get('etag') \ + and response.headers.get('etag') == self.feed['etag']: + logger.debug("%r %r - feed responded with same etag (%d) %r", + self.feed['id'], self.feed['title'], + response.status_code, self.feed['link']) + return + ids, entries = [], {} + parsed_response = feedparser.parse(response.text) + for entry in parsed_response['entries']: + entries[tuple(sorted(extract_id(entry).items()))] = entry + ids.append(extract_id(entry)) + logger.debug('%r %r - found %d entries %r', + self.feed['id'], self.feed['title'], len(ids), ids) + future = self.query_pyagg('get', 'articles/challenge', {'ids': ids}) + updater = PyAggUpdater(self.feed, entries, response.headers, self.auth) + future.add_done_callback(updater.callback) + + +class CrawlerScheduler(AbstractCrawler): + + def __init__(self, username, password): + self.auth = (username, password) + super(CrawlerScheduler, self).__init__(self.auth) + + def prepare_headers(self, feed): + headers = {} + if feed.get('etag', None): + headers['If-None-Match'] = feed['etag'] + elif feed.get('last_modified'): + headers['If-Modified-Since'] = feed['last_modified'] + logger.debug('%r %r - calculated headers %r', + feed['id'], feed['title'], headers) + return headers + + def callback(self, response): + response = response.result() + response.raise_for_status() + feeds = response.json() + logger.debug('%d to fetch %r', len(feeds), feeds) + for feed in feeds: + logger.info('%r %r - fetching resources', + feed['id'], feed['title']) + future = self.session.get(feed['link'], + headers=self.prepare_headers(feed)) + future.add_done_callback(FeedCrawler(feed, self.auth).callback) + + def run(self): + logger.debug('retreving fetchable feed') + future = self.query_pyagg('get', 'feeds/fetchable') + future.add_done_callback(self.callback) -- cgit