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peer_connection_jsep_unittest.cc
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/*
* Copyright 2017 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include <stddef.h>
#include <algorithm>
#include <map>
#include <memory>
#include <string>
#include <tuple>
#include <utility>
#include <vector>
#include "absl/strings/string_view.h"
#include "absl/types/optional.h"
#include "api/audio/audio_device.h"
#include "api/enable_media_with_defaults.h"
#include "api/field_trials_view.h"
#include "api/jsep.h"
#include "api/media_stream_interface.h"
#include "api/media_types.h"
#include "api/peer_connection_interface.h"
#include "api/rtc_error.h"
#include "api/rtp_parameters.h"
#include "api/rtp_receiver_interface.h"
#include "api/rtp_sender_interface.h"
#include "api/rtp_transceiver_direction.h"
#include "api/rtp_transceiver_interface.h"
#include "api/scoped_refptr.h"
#include "api/task_queue/default_task_queue_factory.h"
#include "api/task_queue/task_queue_factory.h"
#include "api/transport/field_trial_based_config.h"
#include "api/transport/sctp_transport_factory_interface.h"
#include "media/base/media_engine.h"
#include "media/base/stream_params.h"
#include "media/engine/webrtc_media_engine.h"
#include "p2p/base/p2p_constants.h"
#include "p2p/base/port_allocator.h"
#include "p2p/base/transport_info.h"
#include "pc/channel_interface.h"
#include "pc/media_session.h"
#include "pc/peer_connection_wrapper.h"
#include "pc/sdp_utils.h"
#include "pc/session_description.h"
#include "pc/test/mock_peer_connection_observers.h"
#include "rtc_base/rtc_certificate_generator.h"
#include "rtc_base/thread.h"
#include "test/gtest.h"
#ifdef WEBRTC_ANDROID
#include "pc/test/android_test_initializer.h"
#endif
#include "pc/test/fake_audio_capture_module.h"
#include "rtc_base/virtual_socket_server.h"
#include "test/gmock.h"
#include "test/pc/sctp/fake_sctp_transport.h"
// This file contains tests that ensure the PeerConnection's implementation of
// CreateOffer/CreateAnswer/SetLocalDescription/SetRemoteDescription conform
// to the JavaScript Session Establishment Protocol (JSEP).
// For now these semantics are only available when configuring the
// PeerConnection with Unified Plan, but eventually that will be the default.
namespace webrtc {
using cricket::MediaContentDescription;
using RTCConfiguration = PeerConnectionInterface::RTCConfiguration;
using ::testing::Combine;
using ::testing::ElementsAre;
using ::testing::UnorderedElementsAre;
using ::testing::Values;
PeerConnectionFactoryDependencies CreatePeerConnectionFactoryDependencies() {
PeerConnectionFactoryDependencies dependencies;
dependencies.worker_thread = rtc::Thread::Current();
dependencies.network_thread = rtc::Thread::Current();
dependencies.signaling_thread = rtc::Thread::Current();
dependencies.task_queue_factory = CreateDefaultTaskQueueFactory();
dependencies.trials = std::make_unique<FieldTrialBasedConfig>();
dependencies.adm = FakeAudioCaptureModule::Create();
EnableMediaWithDefaults(dependencies);
dependencies.sctp_factory = std::make_unique<FakeSctpTransportFactory>();
return dependencies;
}
class PeerConnectionJsepTest : public ::testing::Test {
protected:
typedef std::unique_ptr<PeerConnectionWrapper> WrapperPtr;
PeerConnectionJsepTest()
: vss_(new rtc::VirtualSocketServer()), main_(vss_.get()) {
#ifdef WEBRTC_ANDROID
InitializeAndroidObjects();
#endif
}
WrapperPtr CreatePeerConnection() {
RTCConfiguration config;
config.sdp_semantics = SdpSemantics::kUnifiedPlan;
return CreatePeerConnection(config);
}
WrapperPtr CreatePeerConnection(const RTCConfiguration& config) {
rtc::scoped_refptr<PeerConnectionFactoryInterface> pc_factory =
CreateModularPeerConnectionFactory(
CreatePeerConnectionFactoryDependencies());
auto observer = std::make_unique<MockPeerConnectionObserver>();
auto result = pc_factory->CreatePeerConnectionOrError(
config, PeerConnectionDependencies(observer.get()));
if (!result.ok()) {
return nullptr;
}
observer->SetPeerConnectionInterface(result.value().get());
return std::make_unique<PeerConnectionWrapper>(
pc_factory, result.MoveValue(), std::move(observer));
}
std::unique_ptr<rtc::VirtualSocketServer> vss_;
rtc::AutoSocketServerThread main_;
};
// Tests for JSEP initial offer generation.
// Test that an offer created by a PeerConnection with no transceivers generates
// no media sections.
TEST_F(PeerConnectionJsepTest, EmptyInitialOffer) {
auto caller = CreatePeerConnection();
auto offer = caller->CreateOffer();
ASSERT_EQ(0u, offer->description()->contents().size());
}
// Test that an initial offer with one audio track generates one audio media
// section.
TEST_F(PeerConnectionJsepTest, AudioOnlyInitialOffer) {
auto caller = CreatePeerConnection();
caller->AddTransceiver(cricket::MEDIA_TYPE_AUDIO);
auto offer = caller->CreateOffer();
auto contents = offer->description()->contents();
ASSERT_EQ(1u, contents.size());
EXPECT_EQ(cricket::MEDIA_TYPE_AUDIO, contents[0].media_description()->type());
}
// Test than an initial offer with one video track generates one video media
// section
TEST_F(PeerConnectionJsepTest, VideoOnlyInitialOffer) {
auto caller = CreatePeerConnection();
caller->AddTransceiver(cricket::MEDIA_TYPE_VIDEO);
auto offer = caller->CreateOffer();
auto contents = offer->description()->contents();
ASSERT_EQ(1u, contents.size());
EXPECT_EQ(cricket::MEDIA_TYPE_VIDEO, contents[0].media_description()->type());
}
// Test that an initial offer with one data channel generates one data media
// section.
TEST_F(PeerConnectionJsepTest, DataOnlyInitialOffer) {
auto caller = CreatePeerConnection();
caller->CreateDataChannel("dc");
auto offer = caller->CreateOffer();
auto contents = offer->description()->contents();
ASSERT_EQ(1u, contents.size());
EXPECT_EQ(cricket::MEDIA_TYPE_DATA, contents[0].media_description()->type());
}
// Test that creating multiple data channels only results in one data section
// generated in the offer.
TEST_F(PeerConnectionJsepTest, MultipleDataChannelsCreateOnlyOneDataSection) {
auto caller = CreatePeerConnection();
caller->CreateDataChannel("first");
caller->CreateDataChannel("second");
caller->CreateDataChannel("third");
auto offer = caller->CreateOffer();
ASSERT_EQ(1u, offer->description()->contents().size());
}
// Test that multiple media sections in the initial offer are ordered in the
// order the transceivers were added to the PeerConnection. This is required by
// JSEP section 5.2.1.
TEST_F(PeerConnectionJsepTest, MediaSectionsInInitialOfferOrderedCorrectly) {
auto caller = CreatePeerConnection();
caller->AddTransceiver(cricket::MEDIA_TYPE_VIDEO);
caller->AddTransceiver(cricket::MEDIA_TYPE_AUDIO);
RtpTransceiverInit init;
init.direction = RtpTransceiverDirection::kSendOnly;
caller->AddTransceiver(cricket::MEDIA_TYPE_VIDEO, init);
auto offer = caller->CreateOffer();
auto contents = offer->description()->contents();
ASSERT_EQ(3u, contents.size());
const MediaContentDescription* media_description1 =
contents[0].media_description();
EXPECT_EQ(cricket::MEDIA_TYPE_VIDEO, media_description1->type());
EXPECT_EQ(RtpTransceiverDirection::kSendRecv,
media_description1->direction());
const MediaContentDescription* media_description2 =
contents[1].media_description();
EXPECT_EQ(cricket::MEDIA_TYPE_AUDIO, media_description2->type());
EXPECT_EQ(RtpTransceiverDirection::kSendRecv,
media_description2->direction());
const MediaContentDescription* media_description3 =
contents[2].media_description();
EXPECT_EQ(cricket::MEDIA_TYPE_VIDEO, media_description3->type());
EXPECT_EQ(RtpTransceiverDirection::kSendOnly,
media_description3->direction());
}
// Test that media sections in the initial offer have different mids.
TEST_F(PeerConnectionJsepTest, MediaSectionsInInitialOfferHaveDifferentMids) {
auto caller = CreatePeerConnection();
caller->AddTransceiver(cricket::MEDIA_TYPE_AUDIO);
caller->AddTransceiver(cricket::MEDIA_TYPE_AUDIO);
auto offer = caller->CreateOffer();
auto contents = offer->description()->contents();
ASSERT_EQ(2u, contents.size());
EXPECT_NE(contents[0].name, contents[1].name);
}
TEST_F(PeerConnectionJsepTest,
StoppedTransceiverHasNoMediaSectionInInitialOffer) {
auto caller = CreatePeerConnection();
auto transceiver = caller->AddTransceiver(cricket::MEDIA_TYPE_AUDIO);
transceiver->StopInternal();
auto offer = caller->CreateOffer();
EXPECT_EQ(0u, offer->description()->contents().size());
}
// Tests for JSEP SetLocalDescription with a local offer.
TEST_F(PeerConnectionJsepTest, SetLocalEmptyOfferCreatesNoTransceivers) {
auto caller = CreatePeerConnection();
ASSERT_TRUE(caller->SetLocalDescription(caller->CreateOffer()));
EXPECT_THAT(caller->pc()->GetTransceivers(), ElementsAre());
EXPECT_THAT(caller->pc()->GetSenders(), ElementsAre());
EXPECT_THAT(caller->pc()->GetReceivers(), ElementsAre());
}
TEST_F(PeerConnectionJsepTest, SetLocalOfferSetsTransceiverMid) {
auto caller = CreatePeerConnection();
auto audio_transceiver = caller->AddTransceiver(cricket::MEDIA_TYPE_AUDIO);
auto video_transceiver = caller->AddTransceiver(cricket::MEDIA_TYPE_VIDEO);
auto offer = caller->CreateOffer();
std::string audio_mid = offer->description()->contents()[0].name;
std::string video_mid = offer->description()->contents()[1].name;
ASSERT_TRUE(caller->SetLocalDescription(std::move(offer)));
EXPECT_EQ(audio_mid, audio_transceiver->mid());
EXPECT_EQ(video_mid, video_transceiver->mid());
}
// Tests for JSEP SetRemoteDescription with a remote offer.
// Test that setting a remote offer with sendrecv audio and video creates two
// transceivers, one for receiving audio and one for receiving video.
TEST_F(PeerConnectionJsepTest, SetRemoteOfferCreatesTransceivers) {
auto caller = CreatePeerConnection();
auto caller_audio = caller->AddTransceiver(cricket::MEDIA_TYPE_AUDIO);
auto caller_video = caller->AddTransceiver(cricket::MEDIA_TYPE_VIDEO);
auto callee = CreatePeerConnection();
ASSERT_TRUE(callee->SetRemoteDescription(caller->CreateOfferAndSetAsLocal()));
auto transceivers = callee->pc()->GetTransceivers();
ASSERT_EQ(2u, transceivers.size());
EXPECT_EQ(cricket::MEDIA_TYPE_AUDIO, transceivers[0]->media_type());
EXPECT_EQ(caller_audio->mid(), transceivers[0]->mid());
EXPECT_EQ(RtpTransceiverDirection::kRecvOnly, transceivers[0]->direction());
EXPECT_EQ(0u, transceivers[0]->sender()->stream_ids().size());
EXPECT_EQ(cricket::MEDIA_TYPE_VIDEO, transceivers[1]->media_type());
EXPECT_EQ(caller_video->mid(), transceivers[1]->mid());
EXPECT_EQ(RtpTransceiverDirection::kRecvOnly, transceivers[1]->direction());
EXPECT_EQ(0u, transceivers[1]->sender()->stream_ids().size());
}
// Test that setting a remote offer with an audio track will reuse the
// transceiver created for a local audio track added by AddTrack.
// This is specified in JSEP section 5.10 (Applying a Remote Description). The
// intent is to preserve backwards compatibility with clients who only use the
// AddTrack API.
TEST_F(PeerConnectionJsepTest, SetRemoteOfferReusesTransceiverFromAddTrack) {
auto caller = CreatePeerConnection();
caller->AddAudioTrack("a");
auto caller_audio = caller->pc()->GetTransceivers()[0];
auto callee = CreatePeerConnection();
callee->AddAudioTrack("a");
ASSERT_TRUE(callee->SetRemoteDescription(caller->CreateOfferAndSetAsLocal()));
auto transceivers = callee->pc()->GetTransceivers();
ASSERT_EQ(1u, transceivers.size());
EXPECT_EQ(MediaStreamTrackInterface::kAudioKind,
transceivers[0]->receiver()->track()->kind());
EXPECT_EQ(caller_audio->mid(), transceivers[0]->mid());
}
// Test that setting a remote offer with an audio track marked sendonly will not
// reuse a transceiver created by AddTrack. JSEP only allows the transceiver to
// be reused if the offer direction is sendrecv or recvonly.
TEST_F(PeerConnectionJsepTest,
SetRemoteOfferDoesNotReuseTransceiverIfDirectionSendOnly) {
auto caller = CreatePeerConnection();
caller->AddAudioTrack("a");
auto caller_audio = caller->pc()->GetTransceivers()[0];
caller_audio->SetDirectionWithError(RtpTransceiverDirection::kSendOnly);
auto callee = CreatePeerConnection();
callee->AddAudioTrack("a");
ASSERT_TRUE(callee->SetRemoteDescription(caller->CreateOfferAndSetAsLocal()));
auto transceivers = callee->pc()->GetTransceivers();
ASSERT_EQ(2u, transceivers.size());
EXPECT_EQ(absl::nullopt, transceivers[0]->mid());
EXPECT_EQ(caller_audio->mid(), transceivers[1]->mid());
}
// Test that setting a remote offer with an audio track will not reuse a
// transceiver added by AddTransceiver. The logic for reusing a transceiver is
// specific to those added by AddTrack and is tested above.
TEST_F(PeerConnectionJsepTest,
SetRemoteOfferDoesNotReuseTransceiverFromAddTransceiver) {
auto caller = CreatePeerConnection();
caller->AddAudioTrack("a");
auto callee = CreatePeerConnection();
auto transceiver = callee->AddTransceiver(cricket::MEDIA_TYPE_AUDIO);
ASSERT_TRUE(callee->SetRemoteDescription(caller->CreateOfferAndSetAsLocal()));
auto transceivers = callee->pc()->GetTransceivers();
ASSERT_EQ(2u, transceivers.size());
EXPECT_EQ(absl::nullopt, transceivers[0]->mid());
EXPECT_EQ(caller->pc()->GetTransceivers()[0]->mid(), transceivers[1]->mid());
EXPECT_EQ(MediaStreamTrackInterface::kAudioKind,
transceivers[1]->receiver()->track()->kind());
}
// Test that setting a remote offer with an audio track will not reuse a
// transceiver created for a local video track added by AddTrack.
TEST_F(PeerConnectionJsepTest,
SetRemoteOfferDoesNotReuseTransceiverOfWrongType) {
auto caller = CreatePeerConnection();
caller->AddAudioTrack("a");
auto callee = CreatePeerConnection();
auto video_sender = callee->AddVideoTrack("v");
ASSERT_TRUE(callee->SetRemoteDescription(caller->CreateOfferAndSetAsLocal()));
auto transceivers = callee->pc()->GetTransceivers();
ASSERT_EQ(2u, transceivers.size());
EXPECT_EQ(absl::nullopt, transceivers[0]->mid());
EXPECT_EQ(caller->pc()->GetTransceivers()[0]->mid(), transceivers[1]->mid());
EXPECT_EQ(MediaStreamTrackInterface::kAudioKind,
transceivers[1]->receiver()->track()->kind());
}
// Test that setting a remote offer with an audio track will not reuse a
// stopped transceiver.
TEST_F(PeerConnectionJsepTest, SetRemoteOfferDoesNotReuseStoppedTransceiver) {
auto caller = CreatePeerConnection();
caller->AddAudioTrack("a");
auto callee = CreatePeerConnection();
callee->AddAudioTrack("a");
callee->pc()->GetTransceivers()[0]->StopInternal();
ASSERT_TRUE(callee->SetRemoteDescription(caller->CreateOfferAndSetAsLocal()));
auto transceivers = callee->pc()->GetTransceivers();
ASSERT_EQ(2u, transceivers.size());
// The stopped transceiver is removed in SetLocalDescription(answer)
ASSERT_TRUE(callee->SetLocalDescription(callee->CreateAnswer()));
transceivers = callee->pc()->GetTransceivers();
ASSERT_EQ(1u, transceivers.size());
EXPECT_EQ(caller->pc()->GetTransceivers()[0]->mid(), transceivers[0]->mid());
EXPECT_FALSE(transceivers[0]->stopped());
}
// Test that audio and video transceivers created on the remote side with
// AddTrack will all be reused if there is the same number of audio/video tracks
// in the remote offer. Additionally, this tests that transceivers are
// successfully matched even if they are in a different order on the remote
// side.
TEST_F(PeerConnectionJsepTest, SetRemoteOfferReusesTransceiversOfBothTypes) {
auto caller = CreatePeerConnection();
caller->AddVideoTrack("v");
caller->AddAudioTrack("a");
auto callee = CreatePeerConnection();
callee->AddAudioTrack("a");
callee->AddVideoTrack("v");
ASSERT_TRUE(callee->SetRemoteDescription(caller->CreateOfferAndSetAsLocal()));
auto caller_transceivers = caller->pc()->GetTransceivers();
auto callee_transceivers = callee->pc()->GetTransceivers();
ASSERT_EQ(2u, callee_transceivers.size());
EXPECT_EQ(caller_transceivers[0]->mid(), callee_transceivers[1]->mid());
EXPECT_EQ(caller_transceivers[1]->mid(), callee_transceivers[0]->mid());
}
// Tests for JSEP initial CreateAnswer.
// Test that the answer to a remote offer creates media sections for each
// offered media in the same order and with the same mids.
TEST_F(PeerConnectionJsepTest, CreateAnswerHasSameMidsAsOffer) {
auto caller = CreatePeerConnection();
auto first_transceiver = caller->AddTransceiver(cricket::MEDIA_TYPE_VIDEO);
auto second_transceiver = caller->AddTransceiver(cricket::MEDIA_TYPE_AUDIO);
auto third_transceiver = caller->AddTransceiver(cricket::MEDIA_TYPE_VIDEO);
caller->CreateDataChannel("dc");
auto callee = CreatePeerConnection();
auto offer = caller->CreateOffer();
const auto* offer_data = cricket::GetFirstDataContent(offer->description());
ASSERT_TRUE(
caller->SetLocalDescription(CloneSessionDescription(offer.get())));
ASSERT_TRUE(callee->SetRemoteDescription(std::move(offer)));
auto answer = callee->CreateAnswer();
auto contents = answer->description()->contents();
ASSERT_EQ(4u, contents.size());
EXPECT_EQ(cricket::MEDIA_TYPE_VIDEO, contents[0].media_description()->type());
EXPECT_EQ(first_transceiver->mid(), contents[0].name);
EXPECT_EQ(cricket::MEDIA_TYPE_AUDIO, contents[1].media_description()->type());
EXPECT_EQ(second_transceiver->mid(), contents[1].name);
EXPECT_EQ(cricket::MEDIA_TYPE_VIDEO, contents[2].media_description()->type());
EXPECT_EQ(third_transceiver->mid(), contents[2].name);
EXPECT_EQ(cricket::MEDIA_TYPE_DATA, contents[3].media_description()->type());
EXPECT_EQ(offer_data->name, contents[3].name);
}
// Test that an answering media section is marked as rejected if the underlying
// transceiver has been stopped.
TEST_F(PeerConnectionJsepTest, CreateAnswerRejectsStoppedTransceiver) {
auto caller = CreatePeerConnection();
caller->AddAudioTrack("a");
auto callee = CreatePeerConnection();
ASSERT_TRUE(callee->SetRemoteDescription(caller->CreateOfferAndSetAsLocal()));
callee->pc()->GetTransceivers()[0]->StopInternal();
auto answer = callee->CreateAnswer();
auto contents = answer->description()->contents();
ASSERT_EQ(1u, contents.size());
EXPECT_TRUE(contents[0].rejected);
}
// Test that CreateAnswer will generate media sections which will only send or
// receive if the offer indicates it can do the reciprocating direction.
// The full matrix is tested more extensively in MediaSession.
TEST_F(PeerConnectionJsepTest, CreateAnswerNegotiatesDirection) {
auto caller = CreatePeerConnection();
RtpTransceiverInit init;
init.direction = RtpTransceiverDirection::kSendOnly;
caller->AddTransceiver(cricket::MEDIA_TYPE_AUDIO, init);
auto callee = CreatePeerConnection();
callee->AddAudioTrack("a");
ASSERT_TRUE(callee->SetRemoteDescription(caller->CreateOfferAndSetAsLocal()));
auto answer = callee->CreateAnswer();
auto contents = answer->description()->contents();
ASSERT_EQ(1u, contents.size());
EXPECT_EQ(RtpTransceiverDirection::kRecvOnly,
contents[0].media_description()->direction());
}
// Tests for JSEP SetLocalDescription with a local answer.
// Note that these test only the additional behaviors not covered by
// SetLocalDescription with a local offer.
// Test that SetLocalDescription with an answer sets the current_direction
// property of the transceivers mentioned in the session description.
TEST_F(PeerConnectionJsepTest, SetLocalAnswerUpdatesCurrentDirection) {
auto caller = CreatePeerConnection();
auto caller_audio = caller->AddTransceiver(cricket::MEDIA_TYPE_AUDIO);
caller_audio->SetDirectionWithError(RtpTransceiverDirection::kRecvOnly);
auto callee = CreatePeerConnection();
callee->AddAudioTrack("a");
ASSERT_TRUE(callee->SetRemoteDescription(caller->CreateOfferAndSetAsLocal()));
ASSERT_TRUE(callee->SetLocalDescription(callee->CreateAnswer()));
auto transceivers = callee->pc()->GetTransceivers();
ASSERT_EQ(1u, transceivers.size());
// Since the offer was recvonly and the transceiver direction is sendrecv,
// the negotiated direction will be sendonly.
EXPECT_EQ(RtpTransceiverDirection::kSendOnly,
transceivers[0]->current_direction());
}
// Tests for JSEP SetRemoteDescription with a remote answer.
// Note that these test only the additional behaviors not covered by
// SetRemoteDescription with a remote offer.
TEST_F(PeerConnectionJsepTest, SetRemoteAnswerUpdatesCurrentDirection) {
auto caller = CreatePeerConnection();
caller->AddAudioTrack("a");
auto callee = CreatePeerConnection();
callee->AddAudioTrack("a");
auto callee_audio = callee->pc()->GetTransceivers()[0];
callee_audio->SetDirectionWithError(RtpTransceiverDirection::kSendOnly);
ASSERT_TRUE(callee->SetRemoteDescription(caller->CreateOfferAndSetAsLocal()));
ASSERT_TRUE(
caller->SetRemoteDescription(callee->CreateAnswerAndSetAsLocal()));
auto transceivers = caller->pc()->GetTransceivers();
ASSERT_EQ(1u, transceivers.size());
// Since the remote transceiver was set to sendonly, the negotiated direction
// in the answer would be sendonly which we apply as recvonly to the local
// transceiver.
EXPECT_EQ(RtpTransceiverDirection::kRecvOnly,
transceivers[0]->current_direction());
}
TEST_F(PeerConnectionJsepTest,
ChangeDirectionFromRecvOnlyToSendRecvDoesNotBreakVideoNegotiation) {
auto caller = CreatePeerConnection();
auto caller_transceiver = caller->AddTransceiver(cricket::MEDIA_TYPE_VIDEO);
auto callee = CreatePeerConnection();
caller_transceiver->SetDirectionWithError(RtpTransceiverDirection::kRecvOnly);
ASSERT_TRUE(callee->SetRemoteDescription(caller->CreateOfferAndSetAsLocal()));
ASSERT_TRUE(
caller->SetRemoteDescription(callee->CreateAnswerAndSetAsLocal()));
caller_transceiver->SetDirectionWithError(RtpTransceiverDirection::kSendRecv);
ASSERT_TRUE(callee->SetRemoteDescription(caller->CreateOfferAndSetAsLocal()));
ASSERT_TRUE(
caller->SetRemoteDescription(callee->CreateAnswerAndSetAsLocal()));
}
TEST_F(PeerConnectionJsepTest,
ChangeDirectionFromRecvOnlyToSendRecvDoesNotBreakAudioNegotiation) {
auto caller = CreatePeerConnection();
auto caller_transceiver = caller->AddTransceiver(cricket::MEDIA_TYPE_AUDIO);
auto callee = CreatePeerConnection();
caller_transceiver->SetDirectionWithError(RtpTransceiverDirection::kRecvOnly);
ASSERT_TRUE(callee->SetRemoteDescription(caller->CreateOfferAndSetAsLocal()));
ASSERT_TRUE(
caller->SetRemoteDescription(callee->CreateAnswerAndSetAsLocal()));
caller_transceiver->SetDirectionWithError(RtpTransceiverDirection::kSendRecv);
ASSERT_TRUE(callee->SetRemoteDescription(caller->CreateOfferAndSetAsLocal()));
ASSERT_TRUE(
caller->SetRemoteDescription(callee->CreateAnswerAndSetAsLocal()));
}
// Tests for multiple round trips.
// Test that setting a transceiver with the inactive direction does not stop it
// on either the caller or the callee.
TEST_F(PeerConnectionJsepTest, SettingTransceiverInactiveDoesNotStopIt) {
auto caller = CreatePeerConnection();
caller->AddAudioTrack("a");
auto callee = CreatePeerConnection();
callee->AddAudioTrack("a");
callee->pc()->GetTransceivers()[0]->SetDirectionWithError(
RtpTransceiverDirection::kInactive);
ASSERT_TRUE(callee->SetRemoteDescription(caller->CreateOfferAndSetAsLocal()));
ASSERT_TRUE(
caller->SetRemoteDescription(callee->CreateAnswerAndSetAsLocal()));
EXPECT_FALSE(caller->pc()->GetTransceivers()[0]->stopped());
EXPECT_FALSE(callee->pc()->GetTransceivers()[0]->stopped());
}
// Test that if a transceiver had been associated and later stopped, then a
// media section is still generated for it and the media section is marked as
// rejected.
TEST_F(PeerConnectionJsepTest,
ReOfferMediaSectionForAssociatedStoppedTransceiverIsRejected) {
auto caller = CreatePeerConnection();
auto transceiver = caller->AddTransceiver(cricket::MEDIA_TYPE_AUDIO);
auto callee = CreatePeerConnection();
ASSERT_TRUE(callee->SetRemoteDescription(caller->CreateOfferAndSetAsLocal()));
ASSERT_TRUE(
caller->SetRemoteDescription(callee->CreateAnswerAndSetAsLocal()));
ASSERT_TRUE(transceiver->mid());
transceiver->StopInternal();
auto reoffer = caller->CreateOffer();
auto contents = reoffer->description()->contents();
ASSERT_EQ(1u, contents.size());
EXPECT_TRUE(contents[0].rejected);
}
// Test that stopping an associated transceiver on the caller side will stop the
// corresponding transceiver on the remote side when the remote offer is
// applied.
TEST_F(PeerConnectionJsepTest,
StoppingTransceiverInOfferStopsTransceiverOnRemoteSide) {
auto caller = CreatePeerConnection();
auto transceiver = caller->AddTransceiver(cricket::MEDIA_TYPE_AUDIO);
auto callee = CreatePeerConnection();
ASSERT_TRUE(callee->SetRemoteDescription(caller->CreateOfferAndSetAsLocal()));
ASSERT_TRUE(
caller->SetRemoteDescription(callee->CreateAnswerAndSetAsLocal()));
transceiver->StopInternal();
ASSERT_TRUE(callee->SetRemoteDescription(caller->CreateOfferAndSetAsLocal()));
auto transceivers = callee->pc()->GetTransceivers();
EXPECT_EQ(1u, transceivers.size());
ASSERT_TRUE(callee->SetLocalDescription(callee->CreateAnswer()));
transceivers = callee->pc()->GetTransceivers();
EXPECT_EQ(0u, transceivers.size());
}
// Test that CreateOffer will only generate a recycled media section if the
// transceiver to be recycled has been seen stopped by the other side first.
TEST_F(PeerConnectionJsepTest,
CreateOfferDoesNotRecycleMediaSectionIfFirstStopped) {
auto caller = CreatePeerConnection();
auto first_transceiver = caller->AddTransceiver(cricket::MEDIA_TYPE_AUDIO);
auto callee = CreatePeerConnection();
ASSERT_TRUE(callee->SetRemoteDescription(caller->CreateOfferAndSetAsLocal()));
ASSERT_TRUE(
caller->SetRemoteDescription(callee->CreateAnswerAndSetAsLocal()));
auto second_transceiver = caller->AddTransceiver(cricket::MEDIA_TYPE_AUDIO);
first_transceiver->StopInternal();
auto reoffer = caller->CreateOffer();
auto contents = reoffer->description()->contents();
ASSERT_EQ(2u, contents.size());
EXPECT_TRUE(contents[0].rejected);
EXPECT_FALSE(contents[1].rejected);
}
// Test that the offer/answer and the transceivers are correctly generated and
// updated when the media section is recycled after the callee stops a
// transceiver and sends an answer with a 0 port.
TEST_F(PeerConnectionJsepTest,
RecycleMediaSectionWhenStoppingTransceiverOnAnswerer) {
auto caller = CreatePeerConnection();
auto first_transceiver = caller->AddTransceiver(cricket::MEDIA_TYPE_AUDIO);
auto callee = CreatePeerConnection();
ASSERT_TRUE(callee->SetRemoteDescription(caller->CreateOfferAndSetAsLocal()));
std::string first_mid = *first_transceiver->mid();
ASSERT_EQ(1u, callee->pc()->GetTransceivers().size());
callee->pc()->GetTransceivers()[0]->StopInternal();
ASSERT_EQ(1u, callee->pc()->GetTransceivers().size());
ASSERT_TRUE(
caller->SetRemoteDescription(callee->CreateAnswerAndSetAsLocal()));
EXPECT_TRUE(first_transceiver->stopped());
// First transceivers are dissociated on caller side.
ASSERT_EQ(absl::nullopt, first_transceiver->mid());
// They are disassociated on callee side.
ASSERT_EQ(0u, callee->pc()->GetTransceivers().size());
// New offer exchange with new transceivers that recycles the m section
// correctly.
caller->AddAudioTrack("audio2");
callee->AddAudioTrack("audio2");
auto offer = caller->CreateOffer();
auto offer_contents = offer->description()->contents();
std::string second_mid = offer_contents[0].name;
ASSERT_EQ(1u, offer_contents.size());
EXPECT_FALSE(offer_contents[0].rejected);
EXPECT_NE(first_mid, second_mid);
// Setting the offer on each side will dissociate the first transceivers and
// associate the new transceivers.
ASSERT_TRUE(
caller->SetLocalDescription(CloneSessionDescription(offer.get())));
EXPECT_EQ(absl::nullopt, first_transceiver->mid());
ASSERT_EQ(1u, caller->pc()->GetTransceivers().size());
EXPECT_EQ(second_mid, caller->pc()->GetTransceivers()[0]->mid());
ASSERT_TRUE(callee->SetRemoteDescription(std::move(offer)));
ASSERT_EQ(1u, callee->pc()->GetTransceivers().size());
EXPECT_EQ(second_mid, callee->pc()->GetTransceivers()[0]->mid());
// The new answer should also recycle the m section correctly.
auto answer = callee->CreateAnswer();
auto answer_contents = answer->description()->contents();
ASSERT_EQ(1u, answer_contents.size());
EXPECT_FALSE(answer_contents[0].rejected);
EXPECT_EQ(second_mid, answer_contents[0].name);
// Finishing the negotiation shouldn't add or dissociate any transceivers.
ASSERT_TRUE(
callee->SetLocalDescription(CloneSessionDescription(answer.get())));
ASSERT_TRUE(caller->SetRemoteDescription(std::move(answer)));
auto caller_transceivers = caller->pc()->GetTransceivers();
ASSERT_EQ(1u, caller_transceivers.size());
EXPECT_EQ(second_mid, caller_transceivers[0]->mid());
auto callee_transceivers = callee->pc()->GetTransceivers();
ASSERT_EQ(1u, callee_transceivers.size());
EXPECT_EQ(second_mid, callee_transceivers[0]->mid());
}
// Test that creating/setting a local offer that recycles an m= section is
// idempotent.
TEST_F(PeerConnectionJsepTest, CreateOfferRecyclesWhenOfferingTwice) {
// Do a negotiation with a port 0 for the media section.
auto caller = CreatePeerConnection();
auto first_transceiver = caller->AddTransceiver(cricket::MEDIA_TYPE_AUDIO);
auto callee = CreatePeerConnection();
ASSERT_TRUE(caller->ExchangeOfferAnswerWith(callee.get()));
first_transceiver->StopInternal();
ASSERT_TRUE(caller->ExchangeOfferAnswerWith(callee.get()));
caller->AddAudioTrack("audio2");
// Create a new offer that recycles the media section and set it as a local
// description.
auto offer = caller->CreateOffer();
auto offer_contents = offer->description()->contents();
ASSERT_EQ(1u, offer_contents.size());
EXPECT_FALSE(offer_contents[0].rejected);
ASSERT_TRUE(caller->SetLocalDescription(std::move(offer)));
ASSERT_EQ(1u, caller->pc()->GetTransceivers().size());
EXPECT_FALSE(caller->pc()->GetTransceivers()[0]->stopped());
std::string second_mid = offer_contents[0].name;
// Create another new offer and set the local description again without the
// rest of any negotation ocurring.
auto second_offer = caller->CreateOffer();
auto second_offer_contents = second_offer->description()->contents();
ASSERT_EQ(1u, second_offer_contents.size());
EXPECT_FALSE(second_offer_contents[0].rejected);
// The mid shouldn't change.
EXPECT_EQ(second_mid, second_offer_contents[0].name);
ASSERT_TRUE(caller->SetLocalDescription(std::move(second_offer)));
// Make sure that the caller's transceivers are associated correctly.
auto caller_transceivers = caller->pc()->GetTransceivers();
ASSERT_EQ(1u, caller_transceivers.size());
EXPECT_EQ(second_mid, caller_transceivers[0]->mid());
EXPECT_FALSE(caller_transceivers[0]->stopped());
}
// Test that the offer/answer and transceivers for both the caller and callee
// side are generated/updated correctly when recycling an audio/video media
// section as a media section of either the same or opposite type.
// Correct recycling works as follows:
// - The m= section is re-offered with a new MID value and the new media type.
// - The previously-associated transceiver is dissociated when the new offer is
// set as a local description on the offerer or as a remote description on
// the answerer.
// - The new transceiver is associated with the new MID value.
class RecycleMediaSectionTest
: public PeerConnectionJsepTest,
public ::testing::WithParamInterface<
std::tuple<cricket::MediaType, cricket::MediaType>> {
protected:
RecycleMediaSectionTest() {
first_type_ = std::get<0>(GetParam());
second_type_ = std::get<1>(GetParam());
}
cricket::MediaType first_type_;
cricket::MediaType second_type_;
};
// Test that recycling works properly when a new transceiver recycles an m=
// section that was rejected in both the current local and remote descriptions.
TEST_P(RecycleMediaSectionTest, CurrentLocalAndCurrentRemoteRejected) {
auto caller = CreatePeerConnection();
auto first_transceiver = caller->AddTransceiver(first_type_);
auto callee = CreatePeerConnection();
ASSERT_TRUE(caller->ExchangeOfferAnswerWith(callee.get()));
std::string first_mid = *first_transceiver->mid();
first_transceiver->StopInternal();
ASSERT_TRUE(caller->ExchangeOfferAnswerWith(callee.get()));
auto second_transceiver = caller->AddTransceiver(second_type_);
// The offer should reuse the previous media section but allocate a new MID
// and change the media type.
auto offer = caller->CreateOffer();
auto offer_contents = offer->description()->contents();
ASSERT_EQ(1u, offer_contents.size());
EXPECT_FALSE(offer_contents[0].rejected);
EXPECT_EQ(second_type_, offer_contents[0].media_description()->type());
std::string second_mid = offer_contents[0].name;
EXPECT_NE(first_mid, second_mid);
// Setting the local offer will dissociate the previous transceiver and set
// the MID for the new transceiver.
ASSERT_TRUE(
caller->SetLocalDescription(CloneSessionDescription(offer.get())));
EXPECT_EQ(absl::nullopt, first_transceiver->mid());
EXPECT_EQ(second_mid, second_transceiver->mid());
// Setting the remote offer will dissociate the previous transceiver and
// create a new transceiver for the media section.
ASSERT_TRUE(callee->SetRemoteDescription(std::move(offer)));
auto callee_transceivers = callee->pc()->GetTransceivers();
ASSERT_EQ(1u, callee_transceivers.size());
EXPECT_EQ(second_mid, callee_transceivers[0]->mid());
EXPECT_EQ(second_type_, callee_transceivers[0]->media_type());
// The answer should have only one media section for the new transceiver.
auto answer = callee->CreateAnswer();
auto answer_contents = answer->description()->contents();
ASSERT_EQ(1u, answer_contents.size());
EXPECT_FALSE(answer_contents[0].rejected);
EXPECT_EQ(second_mid, answer_contents[0].name);
EXPECT_EQ(second_type_, answer_contents[0].media_description()->type());
// Setting the local answer should succeed.
ASSERT_TRUE(
callee->SetLocalDescription(CloneSessionDescription(answer.get())));
// Setting the remote answer should succeed and not create any new
// transceivers.
ASSERT_TRUE(caller->SetRemoteDescription(std::move(answer)));
ASSERT_EQ(1u, caller->pc()->GetTransceivers().size());
ASSERT_EQ(1u, callee->pc()->GetTransceivers().size());
}
// Test that recycling works properly when a new transceiver recycles an m=
// section that was rejected in only the current remote description.
TEST_P(RecycleMediaSectionTest, CurrentRemoteOnlyRejected) {
auto caller = CreatePeerConnection();
auto caller_first_transceiver = caller->AddTransceiver(first_type_);
auto callee = CreatePeerConnection();
ASSERT_TRUE(callee->SetRemoteDescription(caller->CreateOfferAndSetAsLocal()));
std::string first_mid = *caller_first_transceiver->mid();
ASSERT_EQ(1u, callee->pc()->GetTransceivers().size());
auto callee_first_transceiver = callee->pc()->GetTransceivers()[0];
callee_first_transceiver->StopInternal();
// The answer will have a rejected m= section.
ASSERT_TRUE(
caller->SetRemoteDescription(callee->CreateAnswerAndSetAsLocal()));
// The offer should reuse the previous media section but allocate a new MID
// and change the media type.
auto caller_second_transceiver = caller->AddTransceiver(second_type_);
auto offer = caller->CreateOffer();
const auto& offer_contents = offer->description()->contents();
ASSERT_EQ(1u, offer_contents.size());
EXPECT_FALSE(offer_contents[0].rejected);
EXPECT_EQ(second_type_, offer_contents[0].media_description()->type());
std::string second_mid = offer_contents[0].name;
EXPECT_NE(first_mid, second_mid);
// Setting the local offer will dissociate the previous transceiver and set
// the MID for the new transceiver.
ASSERT_TRUE(
caller->SetLocalDescription(CloneSessionDescription(offer.get())));
EXPECT_EQ(absl::nullopt, caller_first_transceiver->mid());
EXPECT_EQ(second_mid, caller_second_transceiver->mid());
// Setting the remote offer will dissociate the previous transceiver and
// create a new transceiver for the media section.
ASSERT_TRUE(callee->SetRemoteDescription(std::move(offer)));
auto callee_transceivers = callee->pc()->GetTransceivers();
ASSERT_EQ(1u, callee_transceivers.size());
EXPECT_EQ(second_mid, callee_transceivers[0]->mid());
EXPECT_EQ(second_type_, callee_transceivers[0]->media_type());
// The answer should have only one media section for the new transceiver.
auto answer = callee->CreateAnswer();
auto answer_contents = answer->description()->contents();
ASSERT_EQ(1u, answer_contents.size());
EXPECT_FALSE(answer_contents[0].rejected);
EXPECT_EQ(second_mid, answer_contents[0].name);
EXPECT_EQ(second_type_, answer_contents[0].media_description()->type());
// Setting the local answer should succeed.
ASSERT_TRUE(
callee->SetLocalDescription(CloneSessionDescription(answer.get())));
// Setting the remote answer should succeed and not create any new
// transceivers.
ASSERT_TRUE(caller->SetRemoteDescription(std::move(answer)));
ASSERT_EQ(1u, caller->pc()->GetTransceivers().size());
ASSERT_EQ(1u, callee->pc()->GetTransceivers().size());
}
// Test that recycling works properly when a new transceiver recycles an m=
// section that was rejected only in the current local description.
TEST_P(RecycleMediaSectionTest, CurrentLocalOnlyRejected) {
auto caller = CreatePeerConnection();
auto caller_first_transceiver = caller->AddTransceiver(first_type_);
auto callee = CreatePeerConnection();
ASSERT_TRUE(callee->SetRemoteDescription(caller->CreateOfferAndSetAsLocal()));
std::string first_mid = *caller_first_transceiver->mid();
ASSERT_EQ(1u, callee->pc()->GetTransceivers().size());
auto callee_first_transceiver = callee->pc()->GetTransceivers()[0];
callee_first_transceiver->StopInternal();
// The answer will have a rejected m= section.
ASSERT_TRUE(
caller->SetRemoteDescription(callee->CreateAnswerAndSetAsLocal()));
// The offer should reuse the previous media section but allocate a new MID
// and change the media type.
auto callee_second_transceiver = callee->AddTransceiver(second_type_);
auto offer = callee->CreateOffer();
const auto& offer_contents = offer->description()->contents();
ASSERT_EQ(1u, offer_contents.size());
EXPECT_FALSE(offer_contents[0].rejected);
EXPECT_EQ(second_type_, offer_contents[0].media_description()->type());
std::string second_mid = offer_contents[0].name;
EXPECT_NE(first_mid, second_mid);
// Setting the local offer will dissociate the previous transceiver and set
// the MID for the new transceiver.
ASSERT_TRUE(
callee->SetLocalDescription(CloneSessionDescription(offer.get())));
EXPECT_EQ(absl::nullopt, callee_first_transceiver->mid());
EXPECT_EQ(second_mid, callee_second_transceiver->mid());
// Setting the remote offer will dissociate the previous transceiver and
// create a new transceiver for the media section.
ASSERT_TRUE(caller->SetRemoteDescription(std::move(offer)));
auto caller_transceivers = caller->pc()->GetTransceivers();
ASSERT_EQ(1u, caller_transceivers.size());
EXPECT_EQ(second_mid, caller_transceivers[0]->mid());
EXPECT_EQ(second_type_, caller_transceivers[0]->media_type());
// The answer should have only one media section for the new transceiver.
auto answer = caller->CreateAnswer();
auto answer_contents = answer->description()->contents();
ASSERT_EQ(1u, answer_contents.size());
EXPECT_FALSE(answer_contents[0].rejected);
EXPECT_EQ(second_mid, answer_contents[0].name);
EXPECT_EQ(second_type_, answer_contents[0].media_description()->type());
// Setting the local answer should succeed.
ASSERT_TRUE(
caller->SetLocalDescription(CloneSessionDescription(answer.get())));
// Setting the remote answer should succeed and not create any new
// transceivers.
ASSERT_TRUE(callee->SetRemoteDescription(std::move(answer)));
ASSERT_EQ(1u, callee->pc()->GetTransceivers().size());
ASSERT_EQ(1u, caller->pc()->GetTransceivers().size());
}
// Test that a m= section is *not* recycled if the media section is only
// rejected in the pending local description and there is no current remote
// description.
TEST_P(RecycleMediaSectionTest, PendingLocalRejectedAndNoRemote) {
auto caller = CreatePeerConnection();
auto caller_first_transceiver = caller->AddTransceiver(first_type_);
ASSERT_TRUE(caller->SetLocalDescription(caller->CreateOffer()));
std::string first_mid = *caller_first_transceiver->mid();
caller_first_transceiver->StopInternal();
// The reoffer will have a rejected m= section.
ASSERT_TRUE(caller->SetLocalDescription(caller->CreateOffer()));
auto caller_second_transceiver = caller->AddTransceiver(second_type_);
// The reoffer should not recycle the existing m= section since it is not
// rejected in either the *current* local or *current* remote description.
auto reoffer = caller->CreateOffer();
auto reoffer_contents = reoffer->description()->contents();
ASSERT_EQ(2u, reoffer_contents.size());
EXPECT_TRUE(reoffer_contents[0].rejected);
EXPECT_EQ(first_type_, reoffer_contents[0].media_description()->type());
EXPECT_EQ(first_mid, reoffer_contents[0].name);
EXPECT_FALSE(reoffer_contents[1].rejected);
EXPECT_EQ(second_type_, reoffer_contents[1].media_description()->type());
std::string second_mid = reoffer_contents[1].name;