| # Copyright (c) 2020, Matthew Waters <matthew@centricular.com> | |
| # | |
| # This program is free software; you can redistribute it and/or | |
| # modify it under the terms of the GNU Lesser General Public | |
| # License as published by the Free Software Foundation; either | |
| # version 2.1 of the License, or (at your option) any later version. | |
| # | |
| # This program is distributed in the hope that it will be useful, | |
| # but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| # Lesser General Public License for more details. | |
| # | |
| # You should have received a copy of the GNU Lesser General Public | |
| # License along with this program; if not, write to the | |
| # Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, | |
| # Boston, MA 02110-1301, USA. | |
| import threading | |
| import copy | |
| from observer import Signal, WebRTCObserver, DataChannelObserver, StateObserver | |
| from enums import NegotiationState, DataChannelState | |
| import gi | |
| gi.require_version("Gst", "1.0") | |
| from gi.repository import Gst | |
| gi.require_version("GstWebRTC", "1.0") | |
| from gi.repository import GstWebRTC | |
| gi.require_version("GstSdp", "1.0") | |
| from gi.repository import GstSdp | |
| gi.require_version("GstValidate", "1.0") | |
| from gi.repository import GstValidate | |
| class WebRTCBinObserver(WebRTCObserver): | |
| """ | |
| Observe a webrtcbin element. | |
| """ | |
| def __init__(self, element): | |
| WebRTCObserver.__init__(self) | |
| self.element = element | |
| self.signal_handlers = [] | |
| self.signal_handlers.append(element.connect("on-negotiation-needed", self._on_negotiation_needed)) | |
| self.signal_handlers.append(element.connect("on-ice-candidate", self._on_ice_candidate)) | |
| self.signal_handlers.append(element.connect("pad-added", self._on_pad_added)) | |
| self.signal_handlers.append(element.connect("on-new-transceiver", self._on_new_transceiver)) | |
| self.signal_handlers.append(element.connect("on-data-channel", self._on_data_channel)) | |
| self.negotiation_needed = 0 | |
| self._negotiation_needed_observer = StateObserver(self, "negotiation_needed", threading.Condition()) | |
| self.on_negotiation_needed = Signal() | |
| self.on_ice_candidate = Signal() | |
| self.on_pad_added = Signal() | |
| self.on_new_transceiver = Signal() | |
| def _on_negotiation_needed(self, element): | |
| self.negotiation_needed += 1 | |
| self._negotiation_needed_observer.update(self.negotiation_needed) | |
| self.on_negotiation_needed.fire() | |
| def _on_ice_candidate(self, element, mline, candidate): | |
| self.on_ice_candidate.fire(mline, candidate) | |
| def _on_pad_added(self, element, pad): | |
| self.on_pad_added.fire(pad) | |
| def _on_description_set(self, promise, desc): | |
| new_state = self._update_negotiation_from_description_state(desc) | |
| if new_state == NegotiationState.OFFER_SET: | |
| self.on_offer_set.fire (desc) | |
| elif new_state == NegotiationState.ANSWER_SET: | |
| self.on_answer_set.fire (desc) | |
| def _on_new_transceiver(self, element, transceiver): | |
| self.on_new_transceiver.fire(transceiver) | |
| def _on_data_channel(self, element, channel): | |
| observer = WebRTCBinDataChannelObserver(channel, channel.props.label, 'remote') | |
| self.add_channel(observer) | |
| def _update_negotiation_from_description_state(self, desc): | |
| new_state = None | |
| if desc.type == GstWebRTC.WebRTCSDPType.OFFER: | |
| new_state = NegotiationState.OFFER_SET | |
| elif desc.type == GstWebRTC.WebRTCSDPType.ANSWER: | |
| new_state = NegotiationState.ANSWER_SET | |
| assert new_state is not None | |
| self._update_negotiation_state(new_state) | |
| return new_state | |
| def _deepcopy_session_description(self, desc): | |
| _, new_sdp = GstSdp.SDPMessage.new_from_text(desc.sdp.as_text()) | |
| return GstWebRTC.WebRTCSessionDescription.new(desc.type, new_sdp) | |
| def _on_offer_created(self, promise, element): | |
| self._update_negotiation_state(NegotiationState.OFFER_CREATED) | |
| reply = promise.get_reply() | |
| offer = reply['offer'] | |
| new_offer = self._deepcopy_session_description(offer) | |
| promise = Gst.Promise.new_with_change_func(self._on_description_set, new_offer) | |
| new_offer = self._deepcopy_session_description(offer) | |
| self.element.emit('set-local-description', new_offer, promise) | |
| self.on_offer_created.fire(offer) | |
| def _on_answer_created(self, promise, element): | |
| self._update_negotiation_state(NegotiationState.ANSWER_CREATED) | |
| reply = promise.get_reply() | |
| offer = reply['answer'] | |
| new_offer = self._deepcopy_session_description(offer) | |
| promise = Gst.Promise.new_with_change_func(self._on_description_set, new_offer) | |
| new_offer = self._deepcopy_session_description(offer) | |
| self.element.emit('set-local-description', new_offer, promise) | |
| self.on_answer_created.fire(offer) | |
| def create_offer(self, options=None): | |
| promise = Gst.Promise.new_with_change_func(self._on_offer_created, self.element) | |
| self.element.emit('create-offer', options, promise) | |
| def create_answer(self, options=None): | |
| promise = Gst.Promise.new_with_change_func(self._on_answer_created, self.element) | |
| self.element.emit('create-answer', options, promise) | |
| def set_remote_description(self, desc): | |
| promise = Gst.Promise.new_with_change_func(self._on_description_set, desc) | |
| self.element.emit('set-remote-description', desc, promise) | |
| def add_ice_candidate(self, mline, candidate): | |
| self.element.emit('add-ice-candidate', mline, candidate) | |
| def add_data_channel(self, ident): | |
| channel = self.element.emit('create-data-channel', ident, None) | |
| observer = WebRTCBinDataChannelObserver(channel, ident, 'local') | |
| self.add_channel(observer) | |
| def wait_for_negotiation_needed(self, generation): | |
| self._negotiation_needed_observer.wait_for ((generation,)) | |
| class WebRTCStream(object): | |
| """ | |
| An stream attached to a webrtcbin element | |
| """ | |
| def __init__(self): | |
| self.bin = None | |
| def set_description(self, desc): | |
| assert self.bin is None | |
| self.bin = Gst.parse_bin_from_description(desc, True) | |
| def add_and_link(self, parent, link): | |
| assert self.bin is not None | |
| self.bin.set_locked_state(True) | |
| parent.add(self.bin) | |
| src = self.bin.get_static_pad("src") | |
| sink = self.bin.get_static_pad("sink") | |
| assert src is None or sink is None | |
| if src: | |
| self.bin.link(link) | |
| if sink: | |
| link.link(self.bin) | |
| self.bin.set_locked_state(False) | |
| self.bin.sync_state_with_parent() | |
| def add_and_link_to(self, parent, link, pad): | |
| assert self.bin is not None | |
| self.bin.set_locked_state(True) | |
| parent.add(self.bin) | |
| src = self.bin.get_static_pad("src") | |
| sink = self.bin.get_static_pad("sink") | |
| assert src is None or sink is None | |
| if pad.get_direction() == Gst.PadDirection.SRC: | |
| assert sink is not None | |
| pad.link(sink) | |
| if pad.get_direction() == Gst.PadDirection.SINK: | |
| assert src is not None | |
| src.link(pad) | |
| self.bin.set_locked_state(False) | |
| self.bin.sync_state_with_parent() | |
| class WebRTCClient(WebRTCBinObserver): | |
| """ | |
| Client for performing webrtc operations. Controls the pipeline that | |
| contains a webrtcbin element. | |
| """ | |
| def __init__(self): | |
| self.pipeline = Gst.Pipeline(None) | |
| self.webrtcbin = Gst.ElementFactory.make("webrtcbin") | |
| super().__init__(self.webrtcbin) | |
| self.pipeline.add(self.webrtcbin) | |
| self._streams = [] | |
| def stop(self): | |
| self.pipeline.set_state (Gst.State.NULL) | |
| def add_stream(self, desc): | |
| stream = WebRTCStream() | |
| stream.set_description(desc) | |
| stream.add_and_link (self.pipeline, self.webrtcbin) | |
| self._streams.append(stream) | |
| def add_stream_with_pad(self, desc, pad): | |
| stream = WebRTCStream() | |
| stream.set_description(desc) | |
| stream.add_and_link_to (self.pipeline, self.webrtcbin, pad) | |
| self._streams.append(stream) | |
| def set_options (self, opts): | |
| if opts.has_field("local-bundle-policy"): | |
| self.webrtcbin.props.bundle_policy = opts["local-bundle-policy"] | |
| class WebRTCBinDataChannelObserver(DataChannelObserver): | |
| """ | |
| Data channel observer for a webrtcbin data channel. | |
| """ | |
| def __init__(self, target, ident, location): | |
| super().__init__(ident, location) | |
| self.target = target | |
| self.signal_handlers = [] | |
| self.signal_handlers.append(target.connect("on-open", self._on_open)) | |
| self.signal_handlers.append(target.connect("on-close", self._on_close)) | |
| self.signal_handlers.append(target.connect("on-error", self._on_error)) | |
| self.signal_handlers.append(target.connect("on-message-data", self._on_message_data)) | |
| self.signal_handlers.append(target.connect("on-message-string", self._on_message_string)) | |
| self.signal_handlers.append(target.connect("on-buffered-amount-low", self._on_buffered_amount_low)) | |
| def _on_open(self, channel): | |
| self._update_state (DataChannelState.OPEN) | |
| def _on_close(self, channel): | |
| self._update_state (DataChannelState.CLOSED) | |
| def _on_error(self, channel): | |
| self._update_state (DataChannelState.ERROR) | |
| def _on_message_data(self, channel, data): | |
| self.data.append(msg) | |
| def _on_message_string(self, channel, msg): | |
| self.got_message (msg) | |
| def _on_buffered_amount_low(self, channel): | |
| pass | |
| def close(self): | |
| self.target.emit('close') | |
| def send_string (self, msg): | |
| self.target.emit('send-string', msg) |