Add feedreader component (#1836)

.coveragerc

@@ -92,6 +92,7 @@ omit =
     homeassistant/components/device_tracker/ubus.py
     homeassistant/components/discovery.py
     homeassistant/components/downloader.py
+    homeassistant/components/feedreader.py
     homeassistant/components/garage_door/wink.py
     homeassistant/components/ifttt.py
     homeassistant/components/keyboard.py

homeassistant/components/feedreader.py

@@ -0,0 +1,80 @@
+"""RSS/Atom feed reader for Home Assistant."""
+from datetime import datetime
+from logging import getLogger
+import voluptuous as vol
+from homeassistant.helpers.event import track_utc_time_change
+
+REQUIREMENTS = ['feedparser==5.2.1']
+_LOGGER = getLogger(__name__)
+DOMAIN = "feedreader"
+EVENT_FEEDREADER = "feedreader"
+# pylint: disable=no-value-for-parameter
+CONFIG_SCHEMA = vol.Schema({
+    DOMAIN: {
+        'urls': [vol.Url()],
+    }
+}, extra=vol.ALLOW_EXTRA)
+
+
+# pylint: disable=too-few-public-methods
+class FeedManager(object):
+    """Abstraction over feedparser module."""
+
+    def __init__(self, url, hass):
+        """Initialize the FeedManager object, poll every hour."""
+        self._url = url
+        self._feed = None
+        self._hass = hass
+        # Initialize last entry timestamp as epoch time
+        self._last_entry_timestamp = datetime.utcfromtimestamp(0).timetuple()
+        _LOGGER.debug('Loading feed %s', self._url)
+        self._update()
+        track_utc_time_change(hass, lambda now: self._update(),
+                              minute=0, second=0)
+
+    def _log_no_entries(self):
+        """Send no entries log at debug level."""
+        _LOGGER.debug('No new entries in feed %s', self._url)
+
+    def _update(self):
+        """Update the feed and publish new entries in the event bus."""
+        import feedparser
+        _LOGGER.info('Fetching new data from feed %s', self._url)
+        self._feed = feedparser.parse(self._url,
+                                      etag=None if not self._feed
+                                      else self._feed.get('etag'),
+                                      modified=None if not self._feed
+                                      else self._feed.get('modified'))
+        if not self._feed:
+            _LOGGER.error('Error fetching feed data from %s', self._url)
+        else:
+            if self._feed.bozo != 0:
+                _LOGGER.error('Error parsing feed %s', self._url)
+            # Using etag and modified, if there's no new data available,
+            # the entries list will be empty
+            elif len(self._feed.entries) > 0:
+                _LOGGER.debug('Entries available in feed %s', self._url)
+                self._publish_new_entries()
+                self._last_entry_timestamp = \
+                    self._feed.entries[0].published_parsed
+            else:
+                self._log_no_entries()
+
+    def _publish_new_entries(self):
+        """Publish new entries to the event bus."""
+        new_entries = False
+        for entry in self._feed.entries:
+            # Consider only entries newer then the latest parsed one
+            if entry.published_parsed > self._last_entry_timestamp:
+                new_entries = True
+                entry.update({'feed_url': self._url})
+                self._hass.bus.fire(EVENT_FEEDREADER, entry)
+        if not new_entries:
+            self._log_no_entries()
+
+
+def setup(hass, config):
+    """Setup the feedreader component."""
+    urls = config.get(DOMAIN)['urls']
+    feeds = [FeedManager(url, hass) for url in urls]
+    return len(feeds) > 0

requirements_all.txt

@@ -49,6 +49,9 @@ eliqonline==1.0.11
 # homeassistant.components.thermostat.honeywell
 evohomeclient==0.2.4
 
+# homeassistant.components.feedreader
+feedparser==5.2.1
+
 # homeassistant.components.notify.free_mobile
 freesms==0.1.0