Report error messages and EOS from gstreamer bus.
[toast/stream2beamer.git] / lagarde.py
1 #!/usr/bin/python3
2
3 import argparse
4 import asyncio
5 import json
6 import logging
7 import ssl
8 from typing import Optional, List
9
10 import gi
11 import websockets
12
13 gi.require_version('Gst', '1.0')
14 from gi.repository import Gst
15
16 gi.require_version('GstWebRTC', '1.0')
17 from gi.repository import GstWebRTC
18
19 gi.require_version('GstSdp', '1.0')
20 from gi.repository import GstSdp
21
22 log = logging.getLogger(__name__)
23
24
25 class Lagarde:
26     def __init__(self):
27         self.sdp_offer: Optional[str] = None
28         self.websocket: Optional[websockets.client.WebSocketClientProtocol] = None
29         self.session_id = None
30         self.received_ice_candidates = []
31         self.generated_ice_candidates = []
32         self.user_fragments: Optional[List] = None
33         self.mids: Optional[List] = None
34         self.pipe = None
35         self.webrtcbin = None
36
37     def on_negotiation_needed(self, element):
38         log.info('on_negotiation_needed')
39
40     def on_ice_candidate(self, element, mlineindex, candidate):
41         log.info('on_ice_candidate')
42         self.generated_ice_candidates.append((mlineindex, candidate))
43
44     def webrtcbin_pad_added(self, element, pad):
45         log.info('webrtcbin_pad_added')
46         if pad.direction != Gst.PadDirection.SRC:
47             return
48         decodebin = Gst.ElementFactory.make('decodebin')
49         decodebin.connect('pad-added', self.decodebin_pad_added)
50         self.pipe.add(decodebin)
51         decodebin.sync_state_with_parent()
52         self.webrtcbin.link(decodebin)
53
54     def decodebin_pad_added(self, element, pad):
55         log.info('decodebin_pad_added')
56         if not pad.has_current_caps():
57             log.info(pad, 'has no caps, ignoring')
58             return
59
60         caps = pad.get_current_caps()
61         padsize = caps.get_size()
62         for i in range(padsize):
63             s = caps.get_structure(i) # Gst.Structure
64             name = s.get_name()
65             if name.startswith('video'):
66                 q = Gst.ElementFactory.make('queue')
67                 conv = Gst.ElementFactory.make('videoconvert')
68                 # sink = Gst.ElementFactory.make('autovideosink') # needs XDG_RUNTIME_DIR
69                 sink = Gst.ElementFactory.make('xvimagesink')
70                 self.pipe.add(q)
71                 self.pipe.add(conv)
72                 self.pipe.add(sink)
73                 self.pipe.sync_children_states()
74                 pad.link(q.get_static_pad('sink'))
75                 q.link(conv)
76                 conv.link(sink)
77             elif name.startswith('audio'):
78                 q = Gst.ElementFactory.make('queue')
79                 conv = Gst.ElementFactory.make('audioconvert')
80                 resample = Gst.ElementFactory.make('audioresample')
81                 sink = Gst.ElementFactory.make('autoaudiosink')
82                 self.pipe.add(q)
83                 self.pipe.add(conv)
84                 self.pipe.add(resample)
85                 self.pipe.add(sink)
86                 self.pipe.sync_children_states()
87                 pad.link(q.get_static_pad('sink'))
88                 q.link(conv)
89                 conv.link(resample)
90                 resample.link(sink)
91
92     async def listen_to_gstreamer_bus(self):
93         Gst.init(None)
94         self.webrtcbin = Gst.ElementFactory.make('webrtcbin', 'laplace')
95         self.pipe = Gst.Pipeline.new("pipeline")
96         Gst.Bin.do_add_element(self.pipe, self.webrtcbin)
97         bus = Gst.Pipeline.get_bus(self.pipe)
98         self.webrtcbin.connect('on-negotiation-needed', self.on_negotiation_needed)
99         self.webrtcbin.connect('on-ice-candidate', self.on_ice_candidate)
100         self.webrtcbin.connect('pad-added', self.webrtcbin_pad_added)
101         self.pipe.set_state(Gst.State.PLAYING)
102         try:
103             while True:
104                 if bus.have_pending():
105                     msg = bus.pop()
106                     if msg.type == Gst.MessageType.ERROR:
107                         log.error(f'Error from gstreamer message bus: {msg.get_structure()}')
108                         return
109                     elif msg.type == Gst.MessageType.EOS:  # end of stream
110                         log.info(f'Gstreamer message bus reports end of stream')
111                         return
112                 elif self.sdp_offer is not None:
113                     res, sm = GstSdp.SDPMessage.new()
114                     assert res == GstSdp.SDPResult.OK
115                     GstSdp.sdp_message_parse_buffer(bytes(self.sdp_offer.encode()), sm)
116                     # the three lines above can also be done this way in new versions of GStreamer:
117                     # sm = GstSdp.SDPMessage.new_from_text(sdp_offer)
118                     rd = GstWebRTC.WebRTCSessionDescription.new(GstWebRTC.WebRTCSDPType.OFFER, sm)
119                     gst_promise = Gst.Promise.new()
120                     self.webrtcbin.emit('set-remote-description', rd, gst_promise)
121                     gst_promise.wait()
122                     self.sdp_offer = None
123
124                     log.info('create-answer')
125                     gst_promise = Gst.Promise.new()
126                     self.webrtcbin.emit('create-answer', None, gst_promise)
127                     result = gst_promise.wait()
128                     assert result == Gst.PromiseResult.REPLIED
129                     reply = gst_promise.get_reply()
130                     answer = reply.get_value('answer')
131                     sdp_message = answer.sdp
132                     self.user_fragments = [sdp_message.get_media(i).get_attribute_val('ice-ufrag')
133                                           for i in range(sdp_message.medias_len())]
134                     self.mids = [sdp_message.get_media(i).get_attribute_val('mid')
135                                           for i in range(sdp_message.medias_len())]
136                     sdp_answer = sdp_message.as_text()
137                     log.info(sdp_answer)
138                     sdp_answer_msg = json.dumps({
139                         'SessionID': self.session_id,
140                         'Type': "gotAnswer",
141                         'Value': json.dumps({
142                             'type': 'answer',
143                             'sdp': sdp_answer
144                         })
145                     })
146                     gst_promise = Gst.Promise.new()
147                     self.webrtcbin.emit('set-local-description', answer, gst_promise)
148                     gst_promise.wait()
149                     gst_promise.get_reply()
150                     await self.websocket.send(sdp_answer_msg)
151
152                 elif len(self.received_ice_candidates) > 0:
153                     ic = self.received_ice_candidates.pop(0)
154                     if ic['candidate'] != '':
155                         self.webrtcbin.emit('add-ice-candidate', ic['sdpMLineIndex'], ic['candidate'])
156
157                 elif len(self.generated_ice_candidates) > 0:
158                     mlineindex, candidate = self.generated_ice_candidates.pop(0)
159                     icemsg = json.dumps({
160                         'SessionID': self.session_id,
161                         'Type': 'addCalleeIceCandidate',
162                         'Value': json.dumps({
163                             "candidate": candidate,
164                             "sdpMid": self.mids[mlineindex],
165                             "sdpMLineIndex": mlineindex,
166                             "usernameFragment": self.user_fragments[mlineindex],
167                         })
168                     })
169                     log.info(f'send_ice_candidate_message with {icemsg}')
170                     await self.websocket.send(icemsg)
171
172                 else:
173                     await asyncio.sleep(0.1)
174         finally:
175             self.pipe.set_state(Gst.State.NULL)
176
177     async def talk_to_websocket(self, uri):
178         ssl_context = ssl.SSLContext()
179         ssl_context.check_hostname = False
180         ssl_context.verify_mode = ssl.CERT_NONE
181         async with websockets.connect(uri, ssl=ssl_context) as self.websocket:
182             async for msg in self.websocket:
183                 msg_json = json.loads(msg)
184                 msg_type = msg_json['Type']
185                 msg_value = msg_json['Value']
186                 self.session_id = msg_json['SessionID']
187                 log.info(f"receive for session {self.session_id} type {msg_type}")
188                 if msg_type == 'newSession':
189                     pass
190                 elif msg_type == 'gotOffer':
191                     value_json = json.loads(msg_value)
192                     sdp = value_json['sdp']
193                     log.info(f'SDP: {sdp}')
194                     self.sdp_offer = sdp
195                 elif msg_type == 'addCallerIceCandidate':
196                     value_json = json.loads(msg_value)
197                     log.info(f'ICE: {value_json}')
198                     self.received_ice_candidates.append(value_json)
199                 elif msg_type == 'roomClosed':
200                     log.info('Oh noes, the room went away!')
201                     # and here we should clean up
202                 else:
203                     log.error(f'Unknown message type {msg_type}')
204
205     async def run(self, uri):
206         talk_to_websocket_task = asyncio.Task(self.talk_to_websocket(uri))
207         listen_to_gstreamer_bus_task = asyncio.Task(self.listen_to_gstreamer_bus())
208         done, pending = await asyncio.wait(
209             [talk_to_websocket_task, listen_to_gstreamer_bus_task],
210             return_when=asyncio.FIRST_COMPLETED)
211         for d in done:
212             d.result()
213         for p in pending:
214             p.cancel()
215
216
217 def main():
218     logging.basicConfig(level=logging.INFO, format='%(asctime)-15s %(message)s')
219     parser = argparse.ArgumentParser()
220     parser.add_argument('--uri', default='wss://localhost:1234/ws_connect?id=cug',
221                         help='Signalling server URI')
222     args = parser.parse_args()
223     lagarde = Lagarde()
224     asyncio.run(lagarde.run(args.uri), debug=True)
225
226
227 if __name__ == '__main__':
228     main()