Merge branch 'master' into stream-timeout

4 files changed, 110 insertions, 56 deletions

diff --git a/docs/index.rst b/docs/index.rst
index 5a1254d..4de0f6e 100644
--- a/docs/index.rst
+++ b/docs/index.rst
@@ -725,18 +725,26 @@ Streaming
 ---------
 These functions allow access to the streaming API.
 
-If async is False, these  methods block forever (or until an
-exception is raised).
+If `async` is False, these  methods block forever (or until an error is encountered).
 
-If async is True, the listener will listen on another thread and these methods
-will return a handle corresponding to the open connection. The
-connection may be closed at any time by calling the handles close() method, and the
-status of the connection can be verified calling is_alive() on the handle.
+If `async` is True, the listener will listen on another thread and these methods
+will return a handle corresponding to the open connection. If, in addition, `async_reconnect` is True,
+the thread will attempt to reconnect to the streaming API if any errors are encountered, waiting
+`async_reconnect_wait_sec` seconds between reconnection attempts. Note that no effort is made
+to "catch up" - toots made while the connection is broken will not be received.
+
+The connection may be closed at any time by calling the handles close() method. The 
+current status of the handler thread can be checked with the handles is_alive() function,
+and the streaming status can be checked by calling is_receiving().
 
 The streaming functions take instances of `StreamListener` as the `listener` parameter.
 A `CallbackStreamListener` class that allows you to specify function callbacks 
 directly is included for convenience.
 
+When in not-async mode or async mode without async_reconnect, the stream functions may raise
+various exceptions: `MastodonMalformedEventError` if a received event cannot be parsed and
+`MastodonNetworkError` if any connection problems occur.
+
 .. automethod:: Mastodon.stream_user
 .. automethod:: Mastodon.stream_public
 .. automethod:: Mastodon.stream_local
diff --git a/mastodon/Mastodon.py b/mastodon/Mastodon.py
index ea54649..5461661 100644
--- a/mastodon/Mastodon.py
+++ b/mastodon/Mastodon.py
@@ -90,6 +90,7 @@ class Mastodon:
     __DEFAULT_BASE_URL = 'https://mastodon.social'
     __DEFAULT_TIMEOUT = 300
     __DEFAULT_STREAM_TIMEOUT = 300
+    __DEFAULT_STREAM_RECONNECT_WAIT_SEC = 5
     __SUPPORTED_MASTODON_VERSION = "2.2.0"
     
     ###
@@ -1388,45 +1389,45 @@ class Mastodon:
     # Streaming
     ###
     @api_version("1.1.0", "1.4.2")    
-    def stream_user(self, listener, async=False):
+    def stream_user(self, listener, run_async=False, timeout=__DEFAULT_STREAM_TIMEOUT, reconnect_async=False, reconnect_async_wait_sec=__DEFAULT_STREAM_RECONNECT_WAIT_SEC):
         """
         Streams events that are relevant to the authorized user, i.e. home
         timeline and notifications.
         """
-        return self.__stream('/api/v1/streaming/user', listener, async=async)
+        return self.__stream('/api/v1/streaming/user', listener, run_async=run_async, timeout=timeout, reconnect_async=reconnect_async, reconnect_async_wait_sec=reconnect_async_wait_sec)
 
     @api_version("1.1.0", "1.4.2")
-    def stream_public(self, listener, async=False, timeout=__DEFAULT_STREAM_TIMEOUT):
+    def stream_public(self, listener, run_async=False, timeout=__DEFAULT_STREAM_TIMEOUT, reconnect_async=False, reconnect_async_wait_sec=__DEFAULT_STREAM_RECONNECT_WAIT_SEC):
         """
         Streams public events.
         """
-        return self.__stream('/api/v1/streaming/public', listener, async=async, timeout=timeout)
+        return self.__stream('/api/v1/streaming/public', listener, run_async=run_async, timeout=timeout, reconnect_async=reconnect_async, reconnect_async_wait_sec=reconnect_async_wait_sec)
 
     @api_version("1.1.0", "1.4.2")
-    def stream_local(self, listener, async=False, timeout=__DEFAULT_STREAM_TIMEOUT):
+    def stream_local(self, listener, run_async=False, timeout=__DEFAULT_STREAM_TIMEOUT, reconnect_async=False, reconnect_async_wait_sec=__DEFAULT_STREAM_RECONNECT_WAIT_SEC):
         """
         Streams local public events.
         """
-        return self.__stream('/api/v1/streaming/public/local', listener, async=async, timeout=timeout)
+        return self.__stream('/api/v1/streaming/public/local', listener, run_async=run_async, timeout=timeout, reconnect_async=reconnect_async, reconnect_async_wait_sec=reconnect_async_wait_sec)
 
     @api_version("1.1.0", "1.4.2")
-    def stream_hashtag(self, tag, listener, async=False, timeout=__DEFAULT_STREAM_TIMEOUT):
+    def stream_hashtag(self, tag, listener, run_async=False, timeout=__DEFAULT_STREAM_TIMEOUT, reconnect_async=False, reconnect_async_wait_sec=__DEFAULT_STREAM_RECONNECT_WAIT_SEC):
         """
         Stream for all public statuses for the hashtag 'tag' seen by the connected
         instance.
         """
         if tag.startswith("#"):
             raise MastodonIllegalArgumentError("Tag parameter should omit leading #")
-        return self.__stream("/api/v1/streaming/hashtag?tag={}".format(tag), listener, async=async, timeout=timeout)
+        return self.__stream("/api/v1/streaming/hashtag?tag={}".format(tag), listener, run_async=run_async, timeout=timeout, reconnect_async=reconnect_async, reconnect_async_wait_sec=reconnect_async_wait_sec)
 
     @api_version("2.1.0", "2.1.0")
-    def stream_list(self, id, listener, async=False, timeout=__DEFAULT_STREAM_TIMEOUT):
+    def stream_list(self, id, listener, run_async=False, timeout=__DEFAULT_STREAM_TIMEOUT, reconnect_async=False, reconnect_async_wait_sec=__DEFAULT_STREAM_RECONNECT_WAIT_SEC):
         """
         Stream events for the current user, restricted to accounts on the given
         list. 
         """
         id =  self.__unpack_id(id)
-        return self.__stream("/api/v1/streaming/list?list={}".format(id), listener, async=async, timeout=timeout)
+        return self.__stream("/api/v1/streaming/list?list={}".format(id), listener, run_async=run_async, timeout=timeout, reconnect_async=reconnect_async, reconnect_async_wait_sec=reconnect_async_wait_sec)
     
     ###
     # Internal helpers, dragons probably
@@ -1668,7 +1669,7 @@ class Mastodon:
 
         return response
 
-    def __stream(self, endpoint, listener, params={}, async=False, timeout=__DEFAULT_STREAM_TIMEOUT):
+    def __stream(self, endpoint, listener, params={}, run_async=False, timeout=__DEFAULT_STREAM_TIMEOUT, reconnect_async=False, reconnect_async_wait_sec=__DEFAULT_STREAM_RECONNECT_WAIT_SEC):
         """
         Internal streaming API helper.
 
@@ -1696,19 +1697,29 @@ class Mastodon:
         # The streaming server can't handle two slashes in a path, so remove trailing slashes
         if url[-1] == '/':
             url = url[:-1]
-
-        headers = {"Authorization": "Bearer " + self.access_token}
-        connection = requests.get(url + endpoint, headers = headers, data = params, stream = True,
+        
+        # Connect function (called and then potentially passed to async handler)
+        def connect_func():
+            headers = {"Authorization": "Bearer " + self.access_token}
+            connection = requests.get(url + endpoint, headers = headers, data = params, stream = True,
                                   timeout=(self.request_timeout, timeout))
 
-        if connection.status_code != 200:
-            raise MastodonNetworkError("Could not connect to streaming server: %s" % connection.reason)
-
+            if connection.status_code != 200:
+                raise MastodonNetworkError("Could not connect to streaming server: %s" % connection.reason)
+            return connection
+        connection = connect_func()
+        
+        # Async stream handler
         class __stream_handle():
-            def __init__(self, connection):
+            def __init__(self, connection, connect_func, reconnect_async, reconnect_async_wait_sec):
                 self.closed = False
+                self.running = True
                 self.connection = connection
-
+                self.connect_func = connect_func
+                self.reconnect_async = reconnect_async
+                self.reconnect_async_wait_sec = reconnect_async_wait_sec
+                self.reconnecting = False
+                
             def close(self):
                 self.closed = True
                 self.connection.close()
@@ -1716,19 +1727,48 @@ class Mastodon:
             def is_alive(self):
                 return self._thread.is_alive()
 
+            def is_receiving(self):
+                if self.closed or not self.running or self.reconnecting or not self.is_alive():
+                    return False
+                else:
+                    return True
+
             def _threadproc(self):
                 self._thread = threading.current_thread()
-                with closing(connection) as r:
-                    try:
-                        listener.handle_stream(r)
-                    except AttributeError as e:
-                        if not self.closed:
-                            raise e
+                
+                # Run until closed or until error if not autoreconnecting
+                while self.running:
+                    with closing(self.connection) as r:
+                        try:
+                            listener.handle_stream(r)
+                        except (AttributeError, MastodonMalformedEventError, MastodonNetworkError) as e:
+                            if not (self.closed or self.reconnect_async):
+                                raise e
+                            else:
+                                if self.closed:
+                                    self.running = False
+
+                    # Reconnect loop. Try immediately once, then with delays on error.
+                    if self.reconnect_async and not self.closed:
+                        self.reconnecting = True
+                        connect_success = False
+                        while not connect_success:
+                            connect_success = True
+                            try:
+                                self.connection = self.connect_func()
+                                if self.connection.status_code != 200:
+                                    time.sleep(self.reconnect_async_wait_sec)
+                                    connect_success = False
+                            except:
+                                time.sleep(self.reconnect_async_wait_sec)
+                                connect_success = False
+                        self.reconnecting = False
+                    else:
+                        self.running = False
                 return 0
 
-        handle = __stream_handle(connection)
-
-        if async:
+        if run_async:
+            handle = __stream_handle(connection, connect_func, reconnect_async, reconnect_async_wait_sec)
             t = threading.Thread(args=(), daemon = True, target=handle._threadproc)
             t.start()
             return handle
diff --git a/mastodon/__init__.py b/mastodon/__init__.py
index fdf776d..787d4e8 100644
--- a/mastodon/__init__.py
+++ b/mastodon/__init__.py
@@ -1,4 +1,4 @@
-from mastodon.Mastodon import Mastodon
+from mastodon.Mastodon import Mastodon, MastodonError, MastodonVersionError, MastodonIllegalArgumentError, MastodonIOError, MastodonFileNotFoundError, MastodonNetworkError, MastodonAPIError, MastodonNotFoundError, MastodonUnauthorizedError, MastodonRatelimitError, MastodonMalformedEventError
 from mastodon.streaming import StreamListener, CallbackStreamListener
 
-__all__ = ['Mastodon', 'StreamListener', 'CallbackStreamListener']
+__all__ = ['Mastodon', 'StreamListener', 'CallbackStreamListener', 'MastodonError', 'MastodonVersionError', 'MastodonIllegalArgumentError', 'MastodonIOError', 'MastodonFileNotFoundError', 'MastodonNetworkError', 'MastodonAPIError', 'MastodonNotFoundError', 'MastodonUnauthorizedError', 'MastodonRatelimitError', 'MastodonMalformedEventError']
diff --git a/mastodon/streaming.py b/mastodon/streaming.py
index d55ad54..1c73f48 100644
--- a/mastodon/streaming.py
+++ b/mastodon/streaming.py
@@ -6,7 +6,8 @@ https://github.com/tootsuite/mastodon/blob/master/docs/Using-the-API/Streaming-A
 import json
 import six
 from mastodon import Mastodon
-from mastodon.Mastodon import MastodonMalformedEventError
+from mastodon.Mastodon import MastodonMalformedEventError, MastodonNetworkError
+from requests.exceptions import ChunkedEncodingError
 
 class StreamListener(object):
     """Callbacks for the streaming API. Create a subclass, override the on_xxx
@@ -43,25 +44,31 @@ class StreamListener(object):
         """
         event = {}
         line_buffer = bytearray()
-        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:
-                        six.raise_from(
-                            MastodonMalformedEventError("Malformed UTF-8"),
-                            err
-                        )
-                    if line == '':
-                        self._dispatch(event)
-                        event = {}
+        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:
+                            six.raise_from(
+                                MastodonMalformedEventError("Malformed UTF-8"),
+                                err
+                            )
+                        if line == '':
+                            self._dispatch(event)
+                            event = {}
+                        else:
+                            event = self._parse_line(line, event)
+                        line_buffer = bytearray()
                     else:
-                        event = self._parse_line(line, event)
-                    line_buffer = bytearray()
-                else:
-                    line_buffer.extend(chunk)
-        
+                        line_buffer.extend(chunk)
+        except ChunkedEncodingError as err:
+            six.raise_from(
+                MastodonNetworkError("Server ceased communication."),
+                err
+            )
+            
     def _parse_line(self, line, event):
         if line.startswith(':'):
             self.handle_heartbeat()
@@ -102,7 +109,6 @@ class StreamListener(object):
                err
             )
         else:
-            # TODO: allow handlers to return/raise to stop streaming cleanly
             handler(payload)
 
 class CallbackStreamListener(StreamListener):