path: root/pyaggr3g470r/crawler.py

#! /usr/bin/env python
# -*- coding: utf-8 -

# pyAggr3g470r - A Web based news aggregator.
# Copyright (C) 2010-2015  Cédric Bonhomme - https://www.cedricbonhomme.org
#
# For more information : https://bitbucket.org/cedricbonhomme/pyaggr3g470r/
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

__author__ = "Cedric Bonhomme"
__version__ = "$Revision: 2.2 $"
__date__ = "$Date: 2010/09/02 $"
__revision__ = "$Date: 2014/07/13 $"
__copyright__ = "Copyright (c) Cedric Bonhomme"
__license__ = "AGPLv3"

import re
import socket
import logging
import feedparser
try:
    # Python 3
    from urllib.request import ProxyHandler
except:
    # Python 2
    from urllib2 import ProxyHandler
import requests
import dateutil.parser
from bs4 import BeautifulSoup
from datetime import datetime
from sqlalchemy.exc import IntegrityError
from requests.exceptions import *

import gevent.monkey
gevent.monkey.patch_all()
from gevent import Timeout
from gevent.pool import Pool

from pyaggr3g470r import utils
from pyaggr3g470r import conf
from pyaggr3g470r import notifications
from pyaggr3g470r import db
from pyaggr3g470r.models import User, Article
if not conf.ON_HEROKU:
    import pyaggr3g470r.search as fastsearch


logger = logging.getLogger(__name__)

socket.setdefaulttimeout(5.0)


# Hack: Re-add sslwrap to Python 2.7.9
import inspect
__ssl__ = __import__('ssl')
try:
    _ssl = __ssl__._ssl
except AttributeError:
    _ssl = __ssl__._ssl2
if not hasattr(_ssl, 'sslwrap'):
    def new_sslwrap(sock, server_side=False, keyfile=None, certfile=None, cert_reqs=__ssl__.CERT_NONE, ssl_version=__ssl__.PROTOCOL_SSLv23, ca_certs=None, ciphers=None):
        context = __ssl__.SSLContext(ssl_version)
        context.verify_mode = cert_reqs or __ssl__.CERT_NONE
        if ca_certs:
            context.load_verify_locations(ca_certs)
        if certfile:
            context.load_cert_chain(certfile, keyfile)
        if ciphers:
            context.set_ciphers(ciphers)

        caller_self = inspect.currentframe().f_back.f_locals['self']
        return context._wrap_socket(sock, server_side=server_side, ssl_sock=caller_self)
    _ssl.sslwrap = new_sslwrap
# End hack


class TooLong(Exception):
    def __init__(self):
        """
        Log a when greenlet took to long to fetch a resource.
        """
        logger.warning("Greenlet took to long")


class FeedGetter(object):
    """
    This class is in charge of retrieving the feeds.
    """
    def __init__(self, email):
        """
        Initialization.
        """
        feedparser.USER_AGENT = conf.USER_AGENT
        if conf.HTTP_PROXY == "":
            self.proxy = ProxyHandler({})
            self.proxies = {}
        else:
            self.proxy = ProxyHandler({"http": conf.HTTP_PROXY,
                                               "https": conf.HTTP_PROXY})
            self.proxies = {
                            "http": "http://" + conf.HTTP_PROXY,
                            "https": "http://" + conf.HTTP_PROXY
                           }
        feedparser.USER_AGENT = conf.USER_AGENT
        self.user = User.query.filter(User.email == email).first()

    def retrieve_feed(self, feed_id=None):
        """
        Launch the processus.
        """
        logger.info("Starting to retrieve feeds.")

        # 1 - Get the list of feeds to fetch
        user = User.query.filter(User.email == self.user.email).first()
        feeds = [feed for feed in user.feeds if feed.enabled]
        if feed_id is not None:
            feeds = [feed for feed in feeds if feed.id == feed_id]

        # 2 - Fetch the feeds.
        # 'responses' contains all the jobs returned by
        # the function retrieve_async()
        responses = self.retrieve_async(feeds)
        elements = [item.value for item in responses if item.value is not None]

        # 3 - Insert articles in the database
        new_articles = self.insert_database(elements)

        # 4 - Indexation
        if not conf.ON_HEROKU:
            self.index(new_articles)

        # 5 - Mail notification
        if not conf.ON_HEROKU and conf.NOTIFICATION_ENABLED:
            self.mail_notification(new_articles)

        logger.info("All articles retrieved. End of the processus.")

    def retrieve_async(self, feeds):
        """
        Spawn different jobs in order to retrieve a list of feeds.
        Returns a list of jobs.
        """
        def fetch(feed):
            """
            Fetch a feed.
            """
            logger.info("Fetching the feed: " + feed.title)
            a_feed = feedparser.parse(feed.link, handlers=[self.proxy])
            if a_feed['bozo'] == 1:
                logger.error(a_feed['bozo_exception'])
            if a_feed['entries'] == []:
                return

            # Feed informations
            if feed.title == "":
                try:
                    feed.title = a_feed.feed.title
                except:
                    feed.title = "No title"
            if feed.link == "":
                try:
                    feed.link = a_feed.feed.link
                except:
                    feed.link = ""
            if feed.description == "":
                try:
                    feed.description = a_feed.feed.subtitle
                except:
                    feed.description = ""

            articles = []
            for article in a_feed['entries']:

                try:
                    nice_url = article.link.encode("utf-8")
                except:
                    # if not able to get the link of the article, continue
                    continue
                if conf.RESOLVE_ARTICLE_URL:
                    try:
                        # resolves URL behind proxies
                        # (like feedproxy.google.com)
                        r = requests.get(article.link, timeout=5.0,
                                            proxies=self.proxies)
                        nice_url = r.url.encode("utf-8")
                    except Timeout:
                        logger.warning(
                                "Timeout when getting the real URL of %s.",
                                article.link)
                        continue
                    except Exception as error:
                        logger.warning(
                                "Unable to get the real URL of %s. Error: %s",
                                article.link, error)
                        continue
                # remove utm_* parameters
                nice_url = utils.clean_url(nice_url)

                description = ""
                article_title = article.get('title', '')
                try:
                    # article content
                    description = article.content[0].value
                except AttributeError:
                    # article description
                    description = article.get('description', '')

                try:
                    description = BeautifulSoup(description, "lxml").decode()
                except:
                    logger.error("Problem when sanitizing the content of the article %s (%s)",
                                           article_title, nice_url)

                post_date = None
                for date_key in ('published_parsed', 'published',
                                 'updated_parsed', 'updated'):
                    if not date_key in article:
                        continue

                    try:
                        post_date = dateutil.parser.parse(article[date_key],
                                dayfirst=True)
                        break
                    except:
                        try:  # trying to clean date field from letters
                            post_date = dateutil.parser.parse(
                                        re.sub('[A-z]', '', article[date_key]),
                                        dayfirst=True)
                            break
                        except:
                            pass

                # create the models.Article object and append it to the list of articles
                article = Article(link=nice_url, title=article_title,
                                content=description, readed=False, like=False,
                                date=post_date, user_id=self.user.id,
                                feed_id=feed.id)
                articles.append(article)

            # return the feed with the list of retrieved articles
            return feed, articles

        pool = Pool(20)
        jobs = [pool.spawn(fetch, feed) for feed in feeds]
        pool.join()

        return jobs

    def insert_database(self, elements):
        """
        Insert articles in the database.
        """
        logger.info("Database insertion...")
        new_articles = []
        query1 = Article.query.filter(Article.user_id == self.user.id)
        for feed, articles in elements:
            query2 = query1.filter(Article.feed_id == feed.id)
            for article in articles:
                exist = query2.filter(Article.link == article.link).count() != 0
                if exist:
                    logger.debug("Article %r (%r) already in the database.",
                                 article.title, article.link)
                    continue
                if article.date is None:
                    article.date = datetime.now(dateutil.tz.tzlocal())

                new_articles.append(article)

                try:
                    feed.articles.append(article)
                    #db.session.merge(article)
                    db.session.commit()
                    logger.info("New article %r (%r) added.", article.title,
                                article.link)
                except Exception as e:
                    logger.error("Error when inserting article in database: " + str(e))
                    continue
        #db.session.close()
        return new_articles

    def index(self, new_articles):
        """
        Index new articles.
        """
        logger.info("Indexing new articles.")
        for element in new_articles:
            article = Article.query.filter(Article.user_id == self.user.id,
                                    Article.link == element.link).first()
            try:
                fastsearch.add_to_index(self.user.id, [article],
                                            article.source)
            except:
                logger.exception("Problem during indexation:")
        return True

    def mail_notification(self, new_articles):
        """
        Mail notification.
        """
        logger.info("Starting mail notification.")
        for element in new_articles:
            if element.source.email_notification:
                notifications.new_article_notification(self.user, element.source, element)
        return True