Source code for mastodon.streaming

Handlers for the Streaming API:

import json
import six
from mastodon import Mastodon
from mastodon.Mastodon import MastodonMalformedEventError, MastodonNetworkError, MastodonReadTimeout
from requests.exceptions import ChunkedEncodingError, ReadTimeout

[docs]class StreamListener(object): """Callbacks for the streaming API. Create a subclass, override the on_xxx methods for the kinds of events you're interested in, then pass an instance of your subclass to Mastodon.user_stream(), Mastodon.public_stream(), or Mastodon.hashtag_stream()."""
[docs] def on_update(self, status): """A new status has appeared! 'status' is the parsed JSON dictionary describing the status.""" pass
[docs] def on_notification(self, notification): """A new notification. 'notification' is the parsed JSON dictionary describing the notification.""" pass
[docs] def on_abort(self, err): """There was a connection error, read timeout or other error fatal to the streaming connection. The exception object about to be raised is passed to this function for reference. Note that the exception will be raised properly once you return from this function, so if you are using this handler to reconnect, either never return or start a thread and then catch and ignore the exception. """ pass
[docs] def on_delete(self, status_id): """A status has been deleted. status_id is the status' integer ID.""" pass
[docs] def handle_heartbeat(self): """The server has sent us a keep-alive message. This callback may be useful to carry out periodic housekeeping tasks, or just to confirm that the connection is still open.""" pass
def handle_stream(self, response): """ Handles a stream of events from the Mastodon server. When each event is received, the corresponding .on_[name]() method is called. response; a requests response object with the open stream for reading. """ event = {} line_buffer = bytearray() try: for chunk in response.iter_content(chunk_size = 1): if chunk: if chunk == b'\n': try: line = line_buffer.decode('utf-8') except UnicodeDecodeError as err: exception = MastodonMalformedEventError("Malformed UTF-8") self.on_abort(exception) six.raise_from( exception, err ) if line == '': self._dispatch(event) event = {} else: event = self._parse_line(line, event) line_buffer = bytearray() else: line_buffer.extend(chunk) except ChunkedEncodingError as err: exception = MastodonNetworkError("Server ceased communication.") self.on_abort(exception) six.raise_from( exception, err ) except MastodonReadTimeout as err: exception = MastodonReadTimeout("Timed out while reading from server."), self.on_abort(exception) six.raise_from( exception, err ) def _parse_line(self, line, event): if line.startswith(':'): self.handle_heartbeat() else: try: key, value = line.split(': ', 1) except: exception = MastodonMalformedEventError("Malformed event.") self.on_abort(exception) raise exception # According to the MDN spec, repeating the 'data' key # represents a newline(!) if key in event: event[key] += '\n' + value else: event[key] = value return event def _dispatch(self, event): try: name = event['event'] data = event['data'] payload = json.loads(data, object_hook = Mastodon._Mastodon__json_hooks) except KeyError as err: exception = MastodonMalformedEventError('Missing field', err.args[0], event) self.on_abort(exception) six.raise_from( exception, err ) except ValueError as err: # py2: plain ValueError # py3: json.JSONDecodeError, a subclass of ValueError exception = MastodonMalformedEventError('Bad JSON', data) self.on_abort(exception) six.raise_from( exception, err ) handler_name = 'on_' + name try: handler = getattr(self, handler_name) except AttributeError as err: exception = MastodonMalformedEventError('Bad event type', name) self.on_abort(exception) six.raise_from( exception, err ) else: handler(payload)
[docs]class CallbackStreamListener(StreamListener): """ Simple callback stream handler class. Can optionally additionally send local update events to a separate handler. """ def __init__(self, update_handler = None, local_update_handler = None, delete_handler = None, notification_handler = None): super(CallbackStreamListener, self).__init__() self.update_handler = update_handler self.local_update_handler = local_update_handler self.delete_handler = delete_handler self.notification_handler = notification_handler def on_update(self, status): if self.update_handler != None: self.update_handler(status) try: if self.local_update_handler != None and not "@" in status["account"]["acct"]: self.local_update_handler(status) except Exception as err: six.raise_from( MastodonMalformedEventError('received bad update', status), err ) def on_delete(self, deleted_id): if self.delete_handler != None: self.delete_handler(deleted_id) def on_notification(self, notification): if self.notification_handler != None: self.notification_handler(notification)