scrapymongodb.py

# Copyright 2011 Julien Duponchelle <julien@duponchelle.info>.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

"""MongoDB Pipeline for scrappy"""

import pymongo
from scrapy.conf import settings
from scrapy import log

class MongoDBPipeline(object):
    def __init__(self):
        connection = pymongo.Connection(settings['MONGODB_SERVER'], settings['MONGODB_PORT'])
        self.db = connection[settings['MONGODB_DB']]
        self.collection = self.db[settings['MONGODB_COLLECTION']]
        if self.__get_uniq_key() is not None:
            self.collection.create_index(self.__get_uniq_key(), unique=True)

    def process_item(self, item, spider):
        if self.__get_uniq_key() is None:
            self.collection.insert(dict(item))
        else:
            self.collection.update(
                            {self.__get_uniq_key(): item[self.__get_uniq_key()]},
                            dict(item),
                            upsert=True)  
        log.msg("Item wrote to MongoDB database %s/%s" %
                    (settings['MONGODB_DB'], settings['MONGODB_COLLECTION']),
                    level=log.DEBUG, spider=spider)  
        return item

    def __get_uniq_key(self):
        if not settings['MONGODB_UNIQ_KEY'] or settings['MONGODB_UNIQ_KEY'] == "":
            return None
        return settings['MONGODB_UNIQ_KEY']