path: root/pyaggr3g470r/crawler.py

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

# pyAggr3g470r - A Web based news aggregator.
# Copyright (C) 2010-2014  Cédric Bonhomme - http://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: 2.1 $"
__date__ = "$Date: 2010/09/02 $"
__revision__ = "$Date: 2014/04/13 $"
__copyright__ = "Copyright (c) Cedric Bonhomme"
__license__ = "AGPLv3"

import feedparser
import urllib2
import requests
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

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


pyaggr3g470r_log = log.Log("feedgetter")


class TooLong(Exception):
    def __init__(self):
        """
        Log a when greenlet took to long to fetch a resource.
        """
        pyaggr3g470r_log.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 = urllib2.ProxyHandler({})
            self.proxies = {}
        else:
            self.proxy = urllib2.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.
        """
        pyaggr3g470r_log.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.MAIL_ENABLED:
            self.mail_notification(new_articles)

        pyaggr3g470r_log.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.
            """
            pyaggr3g470r_log.info("Fetching the feed:" + feed.title)
            a_feed = feedparser.parse(feed.link, handlers=[self.proxy])
            if a_feed['entries'] == []:
                return

            # Feed informations
            if feed.title == "":
                try:
                    feed.title = a_feed.feed.title
                except:
                    feed.title = ""
            if feed.description == "":
                try:
                    feed.description = a_feed.feed.subtitle
                except:
                    feed.description = ""

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

                nice_url = article.link.encode("utf-8")
                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:
                        pyaggr3g470r_log.\
                        warning("Timeout when getting the real URL of %s." %
                                    (article.link,))
                        continue
                    except Exception as e:
                        pyaggr3g470r_log.\
                        warning("Unable to get the real URL of %s. Error: %s" %
                                    (article.link, str(e)))
                        continue
                # remove utm_* parameters
                nice_url = utils.clean_url(nice_url)

                description = ""
                article_title = ""
                try:
                    # article content
                    description = article.content[0].value
                except AttributeError:
                    try:
                        # article description
                        description = article.description
                    except Exception:
                        description = ""
                try:
                    description = BeautifulSoup(description, "lxml").decode()
                except Exception as e:
                    pyaggr3g470r_log.error("Problem when sanitizing the content of the article %s (%s)" %
                                            (article_title, nice_url))
                article_title = article.title

                try:
                    post_date = datetime(*article.published_parsed[:6])
                except:
                    post_date = datetime(*article.updated_parsed[:6])

                # 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

        jobs = []
        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.
        """
        pyaggr3g470r_log.info("Database insertion...")
        new_articles = []
        for feed, articles in elements:

            for article in articles:
                

                exist = Article.query.filter(Article.user_id == self.user.id,
                                        Article.feed_id == feed.id,
                                        Article.link == article.link).first()
                if exist is not None:
                    pyaggr3g470r_log.error("Article %s (%s) already in the database." %
                                           (article.title, article.link))
                    continue
                new_articles.append(article)

                try:
                    feed.articles.append(article)
                    #db.session.merge(article)
                    db.session.commit()
                    pyaggr3g470r_log.info("New article %s (%s) added." % (article.title, article.link))
                except IntegrityError:
                    pyaggr3g470r_log.error("Article %s (%s) already in the database." %
                                           (article.title, article.link))
                    articles.remove(article)
                    db.session.rollback()
                    continue
                except Exception as e:
                    pyaggr3g470r_log.error("Error when inserting article in database: " + str(e))
                    continue
        #db.session.close()
        return new_articles

    def index(self, new_articles):
        """
        Index new articles.
        """
        pyaggr3g470r_log.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:
                pyaggr3g470r_log.error("Problem during indexation.")
        return True
    
    def mail_notification(self, new_articles):
        """
        Mail notification.
        """
        pyaggr3g470r_log.info("Starting mail notification.")
        for element in new_articles:
            if element.source.email_notification:
                emails.new_article_notification(self.user, element.source, element)

        return True