--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/backend/arangodb/ArangoBackend.py	Wed Jan 30 07:11:10 2019 +0100
@@ -0,0 +1,53 @@
+# -*- coding: utf-8 -*-
+from argparse import ArgumentParser
+from ArangoDb import ArangoDb
+from backend.AbstractBackend import AbstractBackend
+from Feed import Feed
+from FeedEntry import FeedEntry
+from Preferences import Preferences
+from pyArango.connection import Connection
+
+"""
+Backend that uses ArangoDB for persistence
+"""
+class ArangoBackend(AbstractBackend):
+    def __init__(self):
+        super(ArangoBackend, self).__init__()
+        args = self._parse_arguments()
+        connection = Connection(arangoURL=args.dburl, username=args.user, password=args.password)
+        self.database = ArangoDb(connection[args.dbname])
+        self.prefs = None
+
+    def _parse_arguments(self):
+        parser = ArgumentParser()
+        parser.add_argument('--dburl', nargs='?', help='URL of the database', default='http://127.0.0.1:8529')
+        parser.add_argument('--dbname', nargs='?', help='name of the database', default='feedworm')
+        parser.add_argument('--user', nargs='?', help='username for authenticating the database connection', required=True)
+        parser.add_argument('--password', nargs='?', help='password for authenticating the database connection', required=True)
+        return parser.parse_known_args()[0]
+
+    def preferences(self):
+        if self.prefs is None:
+            self.prefs = Preferences(self.database)
+        return self.prefs
+
+    def getUnreadFeeds(self):
+        return Feed.get_unread(self.database)
+    
+    def _retrieveEntriesForSelectedFeed(self, hideReadEntries):
+        base_query = """
+            FOR feed_entry_doc in feed_entry
+                FILTER feed_entry_doc.feed == @feed_key"""
+        if hideReadEntries:
+            query = base_query + " AND feed_entry_doc.read == false "
+        query = query + " RETURN feed_entry_doc"
+        bind_vars = { 'feed_key': self.selectedFeed._key }
+        results = self.database.AQLQuery(query, bind_vars=bind_vars)
+        return [FeedEntry(doc) for doc in results]
+
+    def _markSelectedFeedEntryRead(self):
+        self.selectedFeedEntry.markRead()
+            
+    def updateAllFeeds(self):
+        for feed in Feed.all_pending_update(self.database):
+            print('updating ' + feed.title)