From 9b2c77380599bb1619b996b4b3a3da423917ceeb Mon Sep 17 00:00:00 2001
From: David Rowe <david@ctrlaltstudio.com>
Date: Tue, 17 Aug 2021 22:37:43 +1200
Subject: [PATCH 1/6] Move WebRTCSignalingServer into Domain Server

---
 domain-server/src/DomainServer.cpp            | 40 +++++++++++++++++++
 domain-server/src/DomainServer.h              | 16 ++++++++
 ice-server/src/IceServer.cpp                  |  1 +
 .../src/BaseAssetScriptingInterface.cpp       |  3 +-
 libraries/networking/src/LimitedNodeList.cpp  |  8 +++-
 libraries/networking/src/LimitedNodeList.h    |  5 ++-
 .../networking/src/udt/NetworkSocket.cpp      |  7 ++++
 libraries/networking/src/udt/NetworkSocket.h  | 11 ++++-
 libraries/networking/src/udt/Socket.cpp       |  6 +++
 libraries/networking/src/udt/Socket.h         |  4 ++
 .../networking/src/webrtc/WebRTCSocket.cpp    | 13 +++---
 .../networking/src/webrtc/WebRTCSocket.h      | 25 ++++++++----
 12 files changed, 119 insertions(+), 20 deletions(-)

diff --git a/domain-server/src/DomainServer.cpp b/domain-server/src/DomainServer.cpp
index c49f175866..341c658ce7 100644
--- a/domain-server/src/DomainServer.cpp
+++ b/domain-server/src/DomainServer.cpp
@@ -167,6 +167,10 @@ DomainServer::DomainServer(int argc, char* argv[]) :
     _gatekeeper(this),
     _httpManager(QHostAddress::AnyIPv4, DOMAIN_SERVER_HTTP_PORT,
         QString("%1/resources/web/").arg(QCoreApplication::applicationDirPath()), this)
+#if defined(WEBRTC_DATA_CHANNELS)
+    ,
+    _webrtcSignalingServer(this)
+#endif
 {
     if (_parentPID != -1) {
         watchParentProcess(_parentPID);
@@ -248,6 +252,10 @@ DomainServer::DomainServer(int argc, char* argv[]) :
     updateDownstreamNodes();
     updateUpstreamNodes();
 
+#if defined(WEBRTC_DATA_CHANNELS)
+    setUpWebRTCSignalingServer();
+#endif
+
     if (_type != NonMetaverse) {
         // if we have a metaverse domain, we'll use an access token for API calls
         resetAccountManagerAccessToken();
@@ -846,6 +854,38 @@ void DomainServer::setupNodeListAndAssignments() {
     addStaticAssignmentsToQueue();
 }
 
+
+#if defined(WEBRTC_DATA_CHANNELS)
+
+void DomainServer::setUpWebRTCSignalingServer() {
+    // Bind the WebRTC signaling server's WebSocket to its port.
+    bool isBound = _webrtcSignalingServer.bind(QHostAddress::AnyIPv4, DEFAULT_DOMAIN_SERVER_WS_PORT);
+    if (!isBound) {
+        qWarning() << "WebRTC signaling server not bound to port. WebRTC connections are not supported.";
+        return;
+    }
+
+    auto limitedNodeList = DependencyManager::get<LimitedNodeList>();
+
+    // Route inbound WebRTC signaling messages received from user clients.
+    connect(&_webrtcSignalingServer, &WebRTCSignalingServer::messageReceived, 
+        this, &DomainServer::routeWebRTCSignalingMessage);
+
+    // Route domain server signaling messages.
+    auto webrtcSocket = limitedNodeList->getWebRTCSocket();
+    connect(this, &DomainServer::webrtcSignalingMessageForDomainServer, webrtcSocket, &WebRTCSocket::onSignalingMessage);
+    connect(webrtcSocket, &WebRTCSocket::sendSignalingMessage, &_webrtcSignalingServer, &WebRTCSignalingServer::sendMessage);
+}
+
+void DomainServer::routeWebRTCSignalingMessage(const QJsonObject& json) {
+    if (json.value("to").toString() == NodeType::DomainServer) {
+        emit webrtcSignalingMessageForDomainServer(json);
+    }
+}
+
+#endif
+
+
 bool DomainServer::resetAccountManagerAccessToken() {
     if (!_oauthProviderURL.isEmpty()) {
         // check for an access-token in our settings, can optionally be overidden by env value
diff --git a/domain-server/src/DomainServer.h b/domain-server/src/DomainServer.h
index bfcc867630..3f509b232d 100644
--- a/domain-server/src/DomainServer.h
+++ b/domain-server/src/DomainServer.h
@@ -27,6 +27,8 @@
 #include <Assignment.h>
 #include <HTTPSConnection.h>
 #include <LimitedNodeList.h>
+#include <shared/WebRTC.h>
+#include <webrtc/WebRTCSignalingServer.h>
 
 #include "AssetsBackupHandler.h"
 #include "DomainGatekeeper.h"
@@ -155,6 +157,11 @@ signals:
     void userConnected();
     void userDisconnected();
 
+#if defined(WEBRTC_DATA_CHANNELS)
+    void webrtcSignalingMessageForDomainServer(const QJsonObject& json);
+#endif
+
+
 private:
     QUuid getID();
 
@@ -235,6 +242,11 @@ private:
                                     std::initializer_list<QString> optionalData = { },
                                     bool requireAccessToken = true);
 
+#if defined(WEBRTC_DATA_CHANNELS)
+    void setUpWebRTCSignalingServer();
+    void routeWebRTCSignalingMessage(const QJsonObject& json);
+#endif
+
     QString operationToString(const QNetworkAccessManager::Operation &op);
 
     SubnetList _acSubnetWhitelist;
@@ -312,6 +324,10 @@ private:
     std::unordered_map<int, std::unique_ptr<QTemporaryFile>> _pendingContentFiles;
 
     QThread _assetClientThread;
+
+#if defined(WEBRTC_DATA_CHANNELS)
+    WebRTCSignalingServer _webrtcSignalingServer;
+#endif
 };
 
 
diff --git a/ice-server/src/IceServer.cpp b/ice-server/src/IceServer.cpp
index 6a6290f7b2..b4542e12a0 100644
--- a/ice-server/src/IceServer.cpp
+++ b/ice-server/src/IceServer.cpp
@@ -16,6 +16,7 @@
 
 #include <QtCore/QDataStream>
 #include <QtCore/QJsonDocument>
+#include <QtCore/QJsonObject>
 #include <QtCore/QTimer>
 #include <QtNetwork/QNetworkReply>
 #include <QtNetwork/QNetworkRequest>
diff --git a/libraries/networking/src/BaseAssetScriptingInterface.cpp b/libraries/networking/src/BaseAssetScriptingInterface.cpp
index d7d14496ba..f9dd12b279 100644
--- a/libraries/networking/src/BaseAssetScriptingInterface.cpp
+++ b/libraries/networking/src/BaseAssetScriptingInterface.cpp
@@ -9,8 +9,9 @@
 
 #include "BaseAssetScriptingInterface.h"
 
-#include <QJsonDocument>
 #include <QJsonArray>
+#include <QJsonDocument>
+#include <QJsonObject>
 #include <QMimeDatabase>
 #include <QThread>
 
diff --git a/libraries/networking/src/LimitedNodeList.cpp b/libraries/networking/src/LimitedNodeList.cpp
index 32e63d4b9a..e742363373 100644
--- a/libraries/networking/src/LimitedNodeList.cpp
+++ b/libraries/networking/src/LimitedNodeList.cpp
@@ -74,7 +74,7 @@ LimitedNodeList::LimitedNodeList(char ownerType, int socketListenPort, int dtlsL
         qCDebug(networking) << "NodeList DTLS socket is listening on" << _dtlsSocket->localPort();
     }
 
-    _nodeSocket.bind(SocketType::WebRTC, QHostAddress::AnyIPv4, DEFAULT_DOMAIN_SERVER_WS_PORT);
+    _nodeSocket.bind(SocketType::WebRTC, QHostAddress::AnyIPv4);
 
     // check for local socket updates every so often
     const int LOCAL_SOCKET_UPDATE_INTERVAL_MSECS = 5 * 1000;
@@ -241,6 +241,12 @@ QUdpSocket& LimitedNodeList::getDTLSSocket() {
     return *_dtlsSocket;
 }
 
+#if defined(WEBRTC_DATA_CHANNELS)
+const WebRTCSocket* LimitedNodeList::getWebRTCSocket() {
+    return _nodeSocket.getWebRTCSocket();
+}
+#endif
+
 bool LimitedNodeList::isPacketVerifiedWithSource(const udt::Packet& packet, Node* sourceNode) {
     // We track bandwidth when doing packet verification to avoid needing to do a node lookup
     // later when we already do it in packetSourceAndHashMatchAndTrackBandwidth. A node lookup
diff --git a/libraries/networking/src/LimitedNodeList.h b/libraries/networking/src/LimitedNodeList.h
index 9e6458225f..81d93bf935 100644
--- a/libraries/networking/src/LimitedNodeList.h
+++ b/libraries/networking/src/LimitedNodeList.h
@@ -37,7 +37,6 @@
 #include <DependencyManager.h>
 #include <SharedUtil.h>
 
-#include "DomainHandler.h"
 #include "NetworkingConstants.h"
 #include "Node.h"
 #include "NLPacket.h"
@@ -139,6 +138,10 @@ public:
     Q_INVOKABLE void setSocketLocalPort(SocketType socketType, quint16 socketLocalPort);
 
     QUdpSocket& getDTLSSocket();
+#if defined(WEBRTC_DATA_CHANNELS)
+    const WebRTCSocket* getWebRTCSocket();
+#endif
+
 
     PacketReceiver& getPacketReceiver() { return *_packetReceiver; }
 
diff --git a/libraries/networking/src/udt/NetworkSocket.cpp b/libraries/networking/src/udt/NetworkSocket.cpp
index 4fdb4e83ff..c882f6dbe3 100644
--- a/libraries/networking/src/udt/NetworkSocket.cpp
+++ b/libraries/networking/src/udt/NetworkSocket.cpp
@@ -267,6 +267,13 @@ QString NetworkSocket::errorString(SocketType socketType) const {
 }
 
 
+#if defined(WEBRTC_DATA_CHANNELS)
+const WebRTCSocket* NetworkSocket::getWebRTCSocket() {
+    return &_webrtcSocket;
+}
+#endif
+
+
 void NetworkSocket::onUDPStateChanged(QAbstractSocket::SocketState socketState) {
     emit stateChanged(SocketType::UDP, socketState);
 }
diff --git a/libraries/networking/src/udt/NetworkSocket.h b/libraries/networking/src/udt/NetworkSocket.h
index 64805282ec..d5891cbde7 100644
--- a/libraries/networking/src/udt/NetworkSocket.h
+++ b/libraries/networking/src/udt/NetworkSocket.h
@@ -91,7 +91,7 @@ public:
     bool hasPendingDatagrams() const;
     
     /// @brief Gets the size of the next pending datagram, alternating between socket types if both have datagrams to read.
-    /// @return The size of the next pendign datagram.
+    /// @return The size of the next pending datagram.
     qint64 pendingDatagramSize();
     
     /// @brief Reads the next datagram per the most recent pendingDatagramSize call if made, otherwise alternating between
@@ -111,7 +111,7 @@ public:
 
     /// @brief Gets the type of error that last occurred.
     /// @param socketType The type of socket for which to get the last error.
-    /// @return The type of error that last occurred
+    /// @return The type of error that last occurred.
     QAbstractSocket::SocketError error(SocketType socketType) const;
 
     /// @brief Gets the description of the error that last occurred.
@@ -119,6 +119,13 @@ public:
     /// @return The description of the error that last occurred.
     QString errorString(SocketType socketType) const;
 
+
+#if defined(WEBRTC_DATA_CHANNELS)
+    /// @brief  @brief Gets a pointer to the WebRTC socket object.
+    /// @return A pointer to the WebRTC socket object.
+    const WebRTCSocket* getWebRTCSocket();
+#endif
+
 signals:
 
     /// @brief Emitted each time new data becomes available for reading.
diff --git a/libraries/networking/src/udt/Socket.cpp b/libraries/networking/src/udt/Socket.cpp
index 8cac4b44c6..810948d742 100644
--- a/libraries/networking/src/udt/Socket.cpp
+++ b/libraries/networking/src/udt/Socket.cpp
@@ -91,6 +91,12 @@ void Socket::rebind(SocketType socketType, quint16 localPort) {
     bind(socketType, QHostAddress::AnyIPv4, localPort);
 }
 
+#if defined(WEBRTC_DATA_CHANNELS)
+const WebRTCSocket* Socket::getWebRTCSocket() {
+    return _networkSocket.getWebRTCSocket();
+}
+#endif
+
 void Socket::setSystemBufferSizes(SocketType socketType) {
     for (int i = 0; i < 2; i++) {
         QAbstractSocket::SocketOption bufferOpt;
diff --git a/libraries/networking/src/udt/Socket.h b/libraries/networking/src/udt/Socket.h
index b92f3fe48d..5c93d96676 100644
--- a/libraries/networking/src/udt/Socket.h
+++ b/libraries/networking/src/udt/Socket.h
@@ -90,6 +90,10 @@ public:
     
     StatsVector sampleStatsForAllConnections();
 
+#if defined(WEBRTC_DATA_CHANNELS)
+    const WebRTCSocket* getWebRTCSocket();
+#endif
+
 #if (PR_BUILD || DEV_BUILD)
     void sendFakedHandshakeRequest(const SockAddr& sockAddr);
 #endif
diff --git a/libraries/networking/src/webrtc/WebRTCSocket.cpp b/libraries/networking/src/webrtc/WebRTCSocket.cpp
index b9eee027a1..2247ad8615 100644
--- a/libraries/networking/src/webrtc/WebRTCSocket.cpp
+++ b/libraries/networking/src/webrtc/WebRTCSocket.cpp
@@ -10,20 +10,19 @@
 
 #if defined(WEBRTC_DATA_CHANNELS)
 
+#include <QHostAddress>
+
 #include "../NetworkLogging.h"
 #include "../udt/Constants.h"
 
 
 WebRTCSocket::WebRTCSocket(QObject* parent, NodeType_t nodeType) :
     QObject(parent),
-    _signalingServer(this /*, QHostAddress::AnyIPv4, DEFAULT_DOMAIN_SERVER_WS_PORT*/),
     _dataChannels(this, nodeType)
 {
-    // Connect WebRTC signaling server and data channels.
-    connect(&_signalingServer, &WebRTCSignalingServer::messageReceived,
-        &_dataChannels, &WebRTCDataChannels::onSignalingMessage);
-    connect(&_dataChannels, &WebRTCDataChannels::signalingMessage,
-        &_signalingServer, &WebRTCSignalingServer::sendMessage);
+    // Route signaling messages.
+    connect(this, &WebRTCSocket::onSignalingMessage, &_dataChannels, &WebRTCDataChannels::onSignalingMessage);
+    connect(&_dataChannels, &WebRTCDataChannels::signalingMessage, this, &WebRTCSocket::sendSignalingMessage);
 
     // Route received data channel messages.
     connect(&_dataChannels, &WebRTCDataChannels::dataMessage, this, &WebRTCSocket::onDataChannelReceivedMessage);
@@ -63,7 +62,7 @@ QVariant WebRTCSocket::socketOption(QAbstractSocket::SocketOption option) {
 bool WebRTCSocket::bind(const QHostAddress& address, quint16 port, QAbstractSocket::BindMode mode) {
     // WebRTC data channels aren't bound to ports so just treat this as a successful operation.
     auto wasBound = _isBound;
-    _isBound = _signalingServer.bind(address, port);
+    _isBound = true;
     if (_isBound != wasBound) {
         emit stateChanged(_isBound ? QAbstractSocket::BoundState : QAbstractSocket::UnconnectedState);
     }
diff --git a/libraries/networking/src/webrtc/WebRTCSocket.h b/libraries/networking/src/webrtc/WebRTCSocket.h
index 8d5d5fc347..9a1d6442d7 100644
--- a/libraries/networking/src/webrtc/WebRTCSocket.h
+++ b/libraries/networking/src/webrtc/WebRTCSocket.h
@@ -18,7 +18,6 @@
 #include <QQueue>
 
 #include "WebRTCDataChannels.h"
-#include "WebRTCSignalingServer.h"
 
 /// @addtogroup Networking
 /// @{
@@ -52,13 +51,14 @@ public:
     /// @return The value of the socket option.
     QVariant socketOption(QAbstractSocket::SocketOption option);
 
-    /// @brief Binds the WebRTC socket's signaling server to an address and port.
-    /// @details Note: WebRTC data connections aren't bound to an address or port. Their ports are negotiated as part of the
+    /// @brief Nominally binds the WebRTC socket to an address and port.
+    /// @details WebRTC data connections aren't actually bound to an address or port. Their ports are negotiated as part of the
     /// WebRTC peer connection process.
-    /// @param address The address to use for the signaling server.
-    /// @param port The port to use for the signaling server.
-    /// @param mode The bind mode. (Not used: included for compatibility with the QUdpSocket interface.)
-    /// @return <code>true</code> if the signaling server was successfully bound, <code>false</code> if it wasn't.
+    /// Included for compatibility with the QUdpSocket interface.
+    /// @param address The address.
+    /// @param port The port.
+    /// @param mode The bind mode.
+    /// @return <code>true</code>.
     bool bind(const QHostAddress& address, quint16 port = 0, QAbstractSocket::BindMode mode
         = QAbstractSocket::DefaultForPlatform);
 
@@ -132,17 +132,26 @@ public slots:
 signals:
 
     /// @brief Emitted when the state of the socket changes.
+    /// @param socketState The new state of the socket.
     void stateChanged(QAbstractSocket::SocketState socketState);
 
     /// @brief Emitted each time new data becomes available for reading.
     void readyRead();
 
+    /// @brief Emitted when a WebRTC signaling message has been received from the signaling server for this WebRTCSocket.
+    /// @param json The signaling message.
+    void onSignalingMessage(const QJsonObject& json);
+
+    /// @brief Emitted when there's a WebRTC signaling message to send via the signaling server.
+    /// @param json The signaling message.
+    void sendSignalingMessage(const QJsonObject& message);
+
+
 private:
 
     void setError(QAbstractSocket::SocketError errorType, QString errorString);
     void clearError();
 
-    WebRTCSignalingServer _signalingServer;
     WebRTCDataChannels _dataChannels;
 
     bool _isBound { false };

From a3c1d504784f1b5fbda1b32a8ab2afb1bfd84940 Mon Sep 17 00:00:00 2001
From: David Rowe <david@ctrlaltstudio.com>
Date: Wed, 18 Aug 2021 20:10:11 +1200
Subject: [PATCH 2/6] WebRTC signaling with assignment clients via domain
 server

---
 assignment-client/src/AssignmentClient.cpp   | 54 ++++++++++++++++++++
 assignment-client/src/AssignmentClient.h     | 19 +++++--
 domain-server/src/DomainServer.cpp           | 33 ++++++++++++
 domain-server/src/DomainServer.h             |  6 +++
 libraries/networking/src/Node.cpp            | 19 +++++++
 libraries/networking/src/NodeType.h          |  1 +
 libraries/networking/src/udt/PacketHeaders.h |  3 +-
 7 files changed, 129 insertions(+), 6 deletions(-)

diff --git a/assignment-client/src/AssignmentClient.cpp b/assignment-client/src/AssignmentClient.cpp
index d1c3efc475..cfe940133f 100644
--- a/assignment-client/src/AssignmentClient.cpp
+++ b/assignment-client/src/AssignmentClient.cpp
@@ -14,6 +14,7 @@
 
 #include <assert.h>
 
+#include <QJsonDocument>
 #include <QProcess>
 #include <QSharedMemory>
 #include <QThread>
@@ -125,6 +126,18 @@ AssignmentClient::AssignmentClient(Assignment::Type requestAssignmentType, QStri
         PacketReceiver::makeUnsourcedListenerReference<AssignmentClient>(this, &AssignmentClient::handleCreateAssignmentPacket));
     packetReceiver.registerListener(PacketType::StopNode,
         PacketReceiver::makeUnsourcedListenerReference<AssignmentClient>(this, &AssignmentClient::handleStopNodePacket));
+
+#if defined(WEBRTC_DATA_CHANNELS)
+    auto webrtcSocket = nodeList->getWebRTCSocket();
+
+    // Route inbound WebRTC signaling messages from the Domain Server.
+    packetReceiver.registerListener(PacketType::WebRTCSignaling,
+        PacketReceiver::makeUnsourcedListenerReference<AssignmentClient>(this, &AssignmentClient::handleWebRTCSignalingPacket));
+    connect(this, &AssignmentClient::webrtcSignalingMessageFromUserClient, webrtcSocket, &WebRTCSocket::onSignalingMessage);
+
+    // Route outbound WebRTC signaling messages via the Domain Server to the user client.
+    connect(webrtcSocket, &WebRTCSocket::sendSignalingMessage, this, &AssignmentClient::sendSignalingMessageToUserClient);
+#endif
 }
 
 void AssignmentClient::stopAssignmentClient() {
@@ -333,3 +346,44 @@ void AssignmentClient::assignmentCompleted() {
     
     _isAssigned = false;
 }
+
+#if defined(WEBRTC_DATA_CHANNELS)
+
+void AssignmentClient::handleWebRTCSignalingPacket(QSharedPointer<ReceivedMessage> message) {
+    auto messageString = message->readString();
+    auto json = QJsonDocument::fromJson(messageString.toUtf8()).object();
+    if (json.keys().contains("echo")) {
+        // Echo message back to sender.
+
+        if (!json.keys().contains("to") || !json.keys().contains("from")) {
+            return;
+        }
+
+        // Swap to/from.
+        auto to = json.value("to");
+        json.insert("to", json.value("from"));
+        json.insert("from", to);
+
+        // Send back to sender via the Domain Server.
+        auto packetList = NLPacketList::create(PacketType::WebRTCSignaling, QByteArray(), true, true);
+        packetList->writeString(QJsonDocument(json).toJson(QJsonDocument::Compact));
+        auto nodeList = DependencyManager::get<NodeList>();
+        auto domainServerAddress = nodeList->getDomainHandler().getSockAddr();
+        nodeList->sendPacketList(std::move(packetList), domainServerAddress);
+
+    } else {
+        // WebRTC signaling message.
+        emit webrtcSignalingMessageFromUserClient(json);
+    }
+}
+
+// Sends a signaling message from the assignment client to the user client via the Domain Server.
+void AssignmentClient::sendSignalingMessageToUserClient(const QJsonObject& json) {
+    auto packetList = NLPacketList::create(PacketType::WebRTCSignaling, QByteArray(), true, true);
+    packetList->writeString(QJsonDocument(json).toJson(QJsonDocument::Compact));
+    auto nodeList = DependencyManager::get<NodeList>();
+    auto domainServerAddress = nodeList->getDomainHandler().getSockAddr();
+    nodeList->sendPacketList(std::move(packetList), domainServerAddress);
+}
+
+#endif
diff --git a/assignment-client/src/AssignmentClient.h b/assignment-client/src/AssignmentClient.h
index c70baf11fd..58e0e8cda1 100644
--- a/assignment-client/src/AssignmentClient.h
+++ b/assignment-client/src/AssignmentClient.h
@@ -16,6 +16,8 @@
 #include <QtCore/QCoreApplication>
 #include <QtCore/QPointer>
 
+#include <shared/WebRTC.h>
+
 #include "ThreadedAssignment.h"
 
 class QSharedMemory;
@@ -29,19 +31,26 @@ public:
                      quint16 assignmentMonitorPort);
     ~AssignmentClient();
 
+public slots:
+    void aboutToQuit();
+
 private slots:
     void sendAssignmentRequest();
     void assignmentCompleted();
     void handleAuthenticationRequest();
     void sendStatusPacketToACM();
     void stopAssignmentClient();
-
-public slots:
-    void aboutToQuit();
-
-private slots:
     void handleCreateAssignmentPacket(QSharedPointer<ReceivedMessage> message);
     void handleStopNodePacket(QSharedPointer<ReceivedMessage> message);
+#if defined(WEBRTC_DATA_CHANNELS)
+    void handleWebRTCSignalingPacket(QSharedPointer<ReceivedMessage> message);
+    void sendSignalingMessageToUserClient(const QJsonObject& json);
+#endif
+
+signals:
+#if defined(WEBRTC_DATA_CHANNELS)
+    void webrtcSignalingMessageFromUserClient(const QJsonObject& json);
+#endif
 
 private:
     void setUpStatusToMonitor();
diff --git a/domain-server/src/DomainServer.cpp b/domain-server/src/DomainServer.cpp
index 341c658ce7..185250e809 100644
--- a/domain-server/src/DomainServer.cpp
+++ b/domain-server/src/DomainServer.cpp
@@ -857,6 +857,7 @@ void DomainServer::setupNodeListAndAssignments() {
 
 #if defined(WEBRTC_DATA_CHANNELS)
 
+// Sets up the WebRTC signaling server that's hosted by the domain server.
 void DomainServer::setUpWebRTCSignalingServer() {
     // Bind the WebRTC signaling server's WebSocket to its port.
     bool isBound = _webrtcSignalingServer.bind(QHostAddress::AnyIPv4, DEFAULT_DOMAIN_SERVER_WS_PORT);
@@ -875,14 +876,46 @@ void DomainServer::setUpWebRTCSignalingServer() {
     auto webrtcSocket = limitedNodeList->getWebRTCSocket();
     connect(this, &DomainServer::webrtcSignalingMessageForDomainServer, webrtcSocket, &WebRTCSocket::onSignalingMessage);
     connect(webrtcSocket, &WebRTCSocket::sendSignalingMessage, &_webrtcSignalingServer, &WebRTCSignalingServer::sendMessage);
+
+    // Forward signaling messages received from assignment clients to user client.
+    PacketReceiver& packetReceiver = limitedNodeList->getPacketReceiver();
+    packetReceiver.registerListener(PacketType::WebRTCSignaling,
+        PacketReceiver::makeUnsourcedListenerReference<DomainServer>(this, 
+            &DomainServer::forwardAssignmentClientSignalingMessageToUserClient));
+    connect(this, &DomainServer::webrtcSignalingMessageForUserClient, 
+        &_webrtcSignalingServer, &WebRTCSignalingServer::sendMessage);
 }
 
+// Routes an inbound WebRTC signaling message received from a client app to the appropriate recipient.
 void DomainServer::routeWebRTCSignalingMessage(const QJsonObject& json) {
     if (json.value("to").toString() == NodeType::DomainServer) {
         emit webrtcSignalingMessageForDomainServer(json);
+    } else {
+        sendWebRTCSignalingMessageToAssignmentClient(json);
     }
 }
 
+// Sends a WebRTC signaling message to the target AC contained in the message.
+void DomainServer::sendWebRTCSignalingMessageToAssignmentClient(const QJsonObject& json) {
+    NodeType_t destinationNodeType = NodeType::fromChar(json.value("to").toString().at(0));
+    auto limitedNodeList = DependencyManager::get<LimitedNodeList>();
+    auto destinationNode = limitedNodeList->soloNodeOfType(destinationNodeType);
+    if (!destinationNode) {
+        return;
+    }
+    // Use an NLPacketList because the signaling message is not necessarily small.
+    auto packetList = NLPacketList::create(PacketType::WebRTCSignaling, QByteArray(), true, true);
+    packetList->writeString(QJsonDocument(json).toJson(QJsonDocument::Compact));
+    limitedNodeList->sendPacketList(std::move(packetList), *destinationNode);
+}
+
+// Forwards a WebRTC signaling message received from an assignment client to the relevant user client.
+void DomainServer::forwardAssignmentClientSignalingMessageToUserClient(QSharedPointer<ReceivedMessage> message) {
+    auto messageString = message->readString();
+    auto json = QJsonDocument::fromJson(messageString.toUtf8()).object();
+    emit webrtcSignalingMessageForUserClient(json);
+}
+
 #endif
 
 
diff --git a/domain-server/src/DomainServer.h b/domain-server/src/DomainServer.h
index 3f509b232d..53f2aec85b 100644
--- a/domain-server/src/DomainServer.h
+++ b/domain-server/src/DomainServer.h
@@ -150,6 +150,10 @@ private slots:
     void tokenGrantFinished();
     void profileRequestFinished();
 
+#if defined(WEBRTC_DATA_CHANNELS)
+    void forwardAssignmentClientSignalingMessageToUserClient(QSharedPointer<ReceivedMessage> message);
+#endif
+
     void aboutToQuit();
 
 signals:
@@ -159,6 +163,7 @@ signals:
 
 #if defined(WEBRTC_DATA_CHANNELS)
     void webrtcSignalingMessageForDomainServer(const QJsonObject& json);
+    void webrtcSignalingMessageForUserClient(const QJsonObject& json);
 #endif
 
 
@@ -245,6 +250,7 @@ private:
 #if defined(WEBRTC_DATA_CHANNELS)
     void setUpWebRTCSignalingServer();
     void routeWebRTCSignalingMessage(const QJsonObject& json);
+    void sendWebRTCSignalingMessageToAssignmentClient(const QJsonObject& json);
 #endif
 
     QString operationToString(const QNetworkAccessManager::Operation &op);
diff --git a/libraries/networking/src/Node.cpp b/libraries/networking/src/Node.cpp
index aa13dd6565..a90da4a929 100644
--- a/libraries/networking/src/Node.cpp
+++ b/libraries/networking/src/Node.cpp
@@ -46,6 +46,22 @@ static const QHash<NodeType_t, QString> TYPE_NAME_HASH {
     { NodeType::Unassigned, "Unassigned" }
 };
 
+static const QHash<NodeType_t, QString> TYPE_CHAR_HASH {
+    { NodeType::DomainServer, "D" },
+    { NodeType::EntityServer, "o" },
+    { NodeType::Agent, "I" },
+    { NodeType::AudioMixer, "M" },
+    { NodeType::AvatarMixer, "W" },
+    { NodeType::AssetServer, "A" },
+    { NodeType::MessagesMixer, "m" },
+    { NodeType::EntityScriptServer, "S" },
+    { NodeType::UpstreamAudioMixer, "B" },
+    { NodeType::UpstreamAvatarMixer, "C" },
+    { NodeType::DownstreamAudioMixer, "a" },
+    { NodeType::DownstreamAvatarMixer, "w" },
+    { NodeType::Unassigned, QChar(1) }
+};
+
 const QString& NodeType::getNodeTypeName(NodeType_t nodeType) {
     const auto matchedTypeName = TYPE_NAME_HASH.find(nodeType);
     return matchedTypeName != TYPE_NAME_HASH.end() ? matchedTypeName.value() : UNKNOWN_NodeType_t_NAME;
@@ -85,6 +101,9 @@ NodeType_t NodeType::fromString(QString type) {
     return TYPE_NAME_HASH.key(type, NodeType::Unassigned);
 }
 
+NodeType_t NodeType::fromChar(QChar type) {
+    return TYPE_CHAR_HASH.key(type, NodeType::Unassigned);
+}
 
 Node::Node(const QUuid& uuid, NodeType_t type, const SockAddr& publicSocket,
     const SockAddr& localSocket, QObject* parent) :
diff --git a/libraries/networking/src/NodeType.h b/libraries/networking/src/NodeType.h
index 8539ce8fb3..55754888c4 100644
--- a/libraries/networking/src/NodeType.h
+++ b/libraries/networking/src/NodeType.h
@@ -43,6 +43,7 @@ namespace NodeType {
     NodeType_t downstreamType(NodeType_t primaryType);
 
     NodeType_t fromString(QString type);
+    NodeType_t fromChar(QChar type);
 }
 
 typedef QSet<NodeType_t> NodeSet;
diff --git a/libraries/networking/src/udt/PacketHeaders.h b/libraries/networking/src/udt/PacketHeaders.h
index d57fa9f663..6fc1b6c157 100644
--- a/libraries/networking/src/udt/PacketHeaders.h
+++ b/libraries/networking/src/udt/PacketHeaders.h
@@ -139,6 +139,7 @@ public:
         BulkAvatarTraitsAck,
         StopInjector,
         AvatarZonePresence,
+        WebRTCSignaling,
         NUM_PACKET_TYPE
     };
 
@@ -190,7 +191,7 @@ public:
             << PacketTypeEnum::Value::ReplicatedMicrophoneAudioWithEcho << PacketTypeEnum::Value::ReplicatedInjectAudio
             << PacketTypeEnum::Value::ReplicatedSilentAudioFrame << PacketTypeEnum::Value::ReplicatedAvatarIdentity
             << PacketTypeEnum::Value::ReplicatedKillAvatar << PacketTypeEnum::Value::ReplicatedBulkAvatarData
-            << PacketTypeEnum::Value::AvatarZonePresence;
+            << PacketTypeEnum::Value::AvatarZonePresence << PacketTypeEnum::Value::WebRTCSignaling;
         return NON_SOURCED_PACKETS;
     }
 

From 5d15ebb7237d37fdc49e8e19dacb4574b03f157d Mon Sep 17 00:00:00 2001
From: David Rowe <david@ctrlaltstudio.com>
Date: Wed, 18 Aug 2021 20:21:56 +1200
Subject: [PATCH 3/6] WebRTC data channel with assignment clients

---
 libraries/networking/src/webrtc/WebRTCDataChannels.cpp | 8 +++++++-
 libraries/networking/src/webrtc/WebRTCDataChannels.h   | 2 +-
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/libraries/networking/src/webrtc/WebRTCDataChannels.cpp b/libraries/networking/src/webrtc/WebRTCDataChannels.cpp
index 974cef2997..c62bca72c4 100644
--- a/libraries/networking/src/webrtc/WebRTCDataChannels.cpp
+++ b/libraries/networking/src/webrtc/WebRTCDataChannels.cpp
@@ -452,12 +452,18 @@ void WebRTCDataChannels::onSignalingMessage(const QJsonObject& message) {
     const int MAX_DEBUG_DETAIL_LENGTH = 64;
     auto data = message.value("data").isObject() ? message.value("data").toObject() : QJsonObject();
     int from = message.value("from").isDouble() ? (quint16)(message.value("from").toInt()) : 0;
-    if (from <= 0 || from > MAXUINT16 || !data.contains("description") && !data.contains("candidate")) {
+    auto to = NodeType::fromChar(message.value("to").toString().at(0));
+
+    if (from <= 0 || from > MAXUINT16 || to == NodeType::Unassigned
+            || !data.contains("description") && !data.contains("candidate")) {
         qCWarning(networking_webrtc) << "Unexpected signaling message:"
             << QJsonDocument(message).toJson(QJsonDocument::Compact).left(MAX_DEBUG_DETAIL_LENGTH);
         return;
     }
 
+    // Remember this node's type for the reply.
+    _nodeType = to;
+
     // Find or create a connection.
     WDCConnection* connection;
     if (_connectionsByWebSocket.contains(from)) {
diff --git a/libraries/networking/src/webrtc/WebRTCDataChannels.h b/libraries/networking/src/webrtc/WebRTCDataChannels.h
index ec6f67b3c7..f6287c3717 100644
--- a/libraries/networking/src/webrtc/WebRTCDataChannels.h
+++ b/libraries/networking/src/webrtc/WebRTCDataChannels.h
@@ -319,7 +319,7 @@ private:
 
     QObject* _parent;
 
-    NodeType_t _nodeType;
+    NodeType_t _nodeType { NodeType::Unassigned };
 
     std::unique_ptr<rtc::Thread> _rtcNetworkThread { nullptr };
     std::unique_ptr<rtc::Thread> _rtcWorkerThread { nullptr };

From ace612d038d4a613089e2c8c0dc1a25aab58117a Mon Sep 17 00:00:00 2001
From: David Rowe <david@ctrlaltstudio.com>
Date: Wed, 18 Aug 2021 21:27:35 +1200
Subject: [PATCH 4/6] Assignment client type is not known at construction

---
 assignment-client/src/AssignmentClientMonitor.cpp      | 2 +-
 domain-server/src/DomainServer.cpp                     | 2 +-
 libraries/networking/src/LimitedNodeList.cpp           | 4 ++--
 libraries/networking/src/LimitedNodeList.h             | 3 +--
 libraries/networking/src/NodeList.cpp                  | 2 +-
 libraries/networking/src/NodeList.h                    | 2 +-
 libraries/networking/src/udt/NetworkSocket.cpp         | 4 ++--
 libraries/networking/src/udt/NetworkSocket.h           | 3 +--
 libraries/networking/src/udt/Socket.cpp                | 4 ++--
 libraries/networking/src/udt/Socket.h                  | 4 ++--
 libraries/networking/src/webrtc/WebRTCDataChannels.cpp | 7 +++----
 libraries/networking/src/webrtc/WebRTCDataChannels.h   | 3 +--
 libraries/networking/src/webrtc/WebRTCSocket.cpp       | 4 ++--
 libraries/networking/src/webrtc/WebRTCSocket.h         | 3 +--
 14 files changed, 21 insertions(+), 26 deletions(-)

diff --git a/assignment-client/src/AssignmentClientMonitor.cpp b/assignment-client/src/AssignmentClientMonitor.cpp
index a2e4d4a697..221a922a4b 100644
--- a/assignment-client/src/AssignmentClientMonitor.cpp
+++ b/assignment-client/src/AssignmentClientMonitor.cpp
@@ -70,7 +70,7 @@ AssignmentClientMonitor::AssignmentClientMonitor(const unsigned int numAssignmen
     // create a NodeList so we can receive stats from children
     DependencyManager::registerInheritance<LimitedNodeList, NodeList>();
     auto addressManager = DependencyManager::set<AddressManager>();
-    auto nodeList = DependencyManager::set<LimitedNodeList>(NodeType::Unassigned, listenPort);
+    auto nodeList = DependencyManager::set<LimitedNodeList>(listenPort);
 
     auto& packetReceiver = DependencyManager::get<NodeList>()->getPacketReceiver();
     packetReceiver.registerListener(PacketType::AssignmentClientStatus,
diff --git a/domain-server/src/DomainServer.cpp b/domain-server/src/DomainServer.cpp
index 185250e809..569e662ae0 100644
--- a/domain-server/src/DomainServer.cpp
+++ b/domain-server/src/DomainServer.cpp
@@ -739,7 +739,7 @@ void DomainServer::setupNodeListAndAssignments() {
     // check for scripts the user wants to persist from their domain-server config
     populateStaticScriptedAssignmentsFromSettings();
 
-    auto nodeList = DependencyManager::set<LimitedNodeList>(NodeType::DomainServer, domainServerPort, domainServerDTLSPort);
+    auto nodeList = DependencyManager::set<LimitedNodeList>(domainServerPort, domainServerDTLSPort);
 
     // no matter the local port, save it to shared mem so that local assignment clients can ask what it is
     nodeList->putLocalPortIntoSharedMemory(DOMAIN_SERVER_LOCAL_PORT_SMEM_KEY, this,
diff --git a/libraries/networking/src/LimitedNodeList.cpp b/libraries/networking/src/LimitedNodeList.cpp
index e742363373..8a551f55cb 100644
--- a/libraries/networking/src/LimitedNodeList.cpp
+++ b/libraries/networking/src/LimitedNodeList.cpp
@@ -50,8 +50,8 @@ static Setting::Handle<quint16> LIMITED_NODELIST_LOCAL_PORT("LimitedNodeList.Loc
 using namespace std::chrono_literals;
 static const std::chrono::milliseconds CONNECTION_RATE_INTERVAL_MS = 1s;
 
-LimitedNodeList::LimitedNodeList(char ownerType, int socketListenPort, int dtlsListenPort) :
-    _nodeSocket(this, true, ownerType),
+LimitedNodeList::LimitedNodeList(int socketListenPort, int dtlsListenPort) :
+    _nodeSocket(this, true),
     _packetReceiver(new PacketReceiver(this))
 {
     qRegisterMetaType<ConnectionStep>("ConnectionStep");
diff --git a/libraries/networking/src/LimitedNodeList.h b/libraries/networking/src/LimitedNodeList.h
index 81d93bf935..2ee863da07 100644
--- a/libraries/networking/src/LimitedNodeList.h
+++ b/libraries/networking/src/LimitedNodeList.h
@@ -416,8 +416,7 @@ protected:
         QUuid connectionSecretUUID;
     };
 
-    LimitedNodeList(char ownerType = NodeType::DomainServer, int socketListenPort = INVALID_PORT, 
-        int dtlsListenPort = INVALID_PORT);
+    LimitedNodeList(int socketListenPort = INVALID_PORT, int dtlsListenPort = INVALID_PORT);
     LimitedNodeList(LimitedNodeList const&) = delete; // Don't implement, needed to avoid copies of singleton
     void operator=(LimitedNodeList const&) = delete; // Don't implement, needed to avoid copies of singleton
 
diff --git a/libraries/networking/src/NodeList.cpp b/libraries/networking/src/NodeList.cpp
index 97080a349a..b8e6cdf80a 100644
--- a/libraries/networking/src/NodeList.cpp
+++ b/libraries/networking/src/NodeList.cpp
@@ -50,7 +50,7 @@ const int KEEPALIVE_PING_INTERVAL_MS = 1000;
 const int MAX_SYSTEM_INFO_SIZE = 1000;
 
 NodeList::NodeList(char newOwnerType, int socketListenPort, int dtlsListenPort) :
-    LimitedNodeList(newOwnerType, socketListenPort, dtlsListenPort),
+    LimitedNodeList(socketListenPort, dtlsListenPort),
     _ownerType(newOwnerType),
     _nodeTypesOfInterest(),
     _domainHandler(this),
diff --git a/libraries/networking/src/NodeList.h b/libraries/networking/src/NodeList.h
index d3999c31f6..7af0dc405f 100644
--- a/libraries/networking/src/NodeList.h
+++ b/libraries/networking/src/NodeList.h
@@ -154,7 +154,7 @@ private slots:
     void maybeSendIgnoreSetToNode(SharedNodePointer node);
 
 private:
-    NodeList() : LimitedNodeList(NodeType::Unassigned, INVALID_PORT, INVALID_PORT) { 
+    NodeList() : LimitedNodeList(INVALID_PORT, INVALID_PORT) { 
         assert(false);  // Not implemented, needed for DependencyManager templates compile
     }
     NodeList(char ownerType, int socketListenPort = INVALID_PORT, int dtlsListenPort = INVALID_PORT);
diff --git a/libraries/networking/src/udt/NetworkSocket.cpp b/libraries/networking/src/udt/NetworkSocket.cpp
index c882f6dbe3..fd646fe317 100644
--- a/libraries/networking/src/udt/NetworkSocket.cpp
+++ b/libraries/networking/src/udt/NetworkSocket.cpp
@@ -11,13 +11,13 @@
 #include "../NetworkLogging.h"
 
 
-NetworkSocket::NetworkSocket(QObject* parent, NodeType_t nodeType) :
+NetworkSocket::NetworkSocket(QObject* parent) :
     QObject(parent),
     _parent(parent),
     _udpSocket(this)
 #if defined(WEBRTC_DATA_CHANNELS)
     ,
-    _webrtcSocket(this, nodeType)
+    _webrtcSocket(this)
 #endif
 {
     connect(&_udpSocket, &QUdpSocket::readyRead, this, &NetworkSocket::readyRead);
diff --git a/libraries/networking/src/udt/NetworkSocket.h b/libraries/networking/src/udt/NetworkSocket.h
index d5891cbde7..2670fa40b8 100644
--- a/libraries/networking/src/udt/NetworkSocket.h
+++ b/libraries/networking/src/udt/NetworkSocket.h
@@ -33,8 +33,7 @@ public:
 
     /// @brief Constructs a new NetworkSocket object.
     /// @param parent Qt parent object.
-    /// @param nodeType The type of node that the NetworkSocket object is being used in.
-    NetworkSocket(QObject* parent, NodeType_t nodeType);
+    NetworkSocket(QObject* parent);
 
 
     /// @brief Set the value of a UDP or WebRTC socket option.
diff --git a/libraries/networking/src/udt/Socket.cpp b/libraries/networking/src/udt/Socket.cpp
index 810948d742..8313a87bbf 100644
--- a/libraries/networking/src/udt/Socket.cpp
+++ b/libraries/networking/src/udt/Socket.cpp
@@ -40,9 +40,9 @@ using namespace udt;
 #endif
 
 
-Socket::Socket(QObject* parent, bool shouldChangeSocketOptions, NodeType_t nodeType) :
+Socket::Socket(QObject* parent, bool shouldChangeSocketOptions) :
     QObject(parent),
-    _networkSocket(parent, nodeType),
+    _networkSocket(parent),
     _readyReadBackupTimer(new QTimer(this)),
     _shouldChangeSocketOptions(shouldChangeSocketOptions)
 {
diff --git a/libraries/networking/src/udt/Socket.h b/libraries/networking/src/udt/Socket.h
index 5c93d96676..ab9699bb8f 100644
--- a/libraries/networking/src/udt/Socket.h
+++ b/libraries/networking/src/udt/Socket.h
@@ -55,8 +55,8 @@ class Socket : public QObject {
 
 public:
     using StatsVector = std::vector<std::pair<SockAddr, ConnectionStats::Stats>>;
-    
-    Socket(QObject* object = 0, bool shouldChangeSocketOptions = true, NodeType_t nodeType = NodeType::Unassigned);
+ 
+    Socket(QObject* object = 0, bool shouldChangeSocketOptions = true);
     
     quint16 localPort(SocketType socketType) const { return _networkSocket.localPort(socketType); }
     
diff --git a/libraries/networking/src/webrtc/WebRTCDataChannels.cpp b/libraries/networking/src/webrtc/WebRTCDataChannels.cpp
index c62bca72c4..3f7b84086d 100644
--- a/libraries/networking/src/webrtc/WebRTCDataChannels.cpp
+++ b/libraries/networking/src/webrtc/WebRTCDataChannels.cpp
@@ -373,13 +373,12 @@ void WDCConnection::closePeerConnection() {
 }
 
 
-WebRTCDataChannels::WebRTCDataChannels(QObject* parent, NodeType_t nodeType) :
+WebRTCDataChannels::WebRTCDataChannels(QObject* parent) :
     QObject(parent),
-    _parent(parent),
-    _nodeType(nodeType)
+    _parent(parent)
 {
 #ifdef WEBRTC_DEBUG
-    qCDebug(networking_webrtc) << "WebRTCDataChannels::WebRTCDataChannels()" << nodeType << NodeType::getNodeTypeName(nodeType);
+    qCDebug(networking_webrtc) << "WebRTCDataChannels::WebRTCDataChannels()";
 #endif
 
     // Create a peer connection factory.
diff --git a/libraries/networking/src/webrtc/WebRTCDataChannels.h b/libraries/networking/src/webrtc/WebRTCDataChannels.h
index f6287c3717..b1751093d5 100644
--- a/libraries/networking/src/webrtc/WebRTCDataChannels.h
+++ b/libraries/networking/src/webrtc/WebRTCDataChannels.h
@@ -227,8 +227,7 @@ public:
 
     /// @brief Constructs a new WebRTCDataChannels object.
     /// @param parent The parent Qt object.
-    /// @param nodeType The type of node that the WebRTCDataChannels object is being used in.
-    WebRTCDataChannels(QObject* parent, NodeType_t nodeType);
+    WebRTCDataChannels(QObject* parent);
 
     /// @brief Destroys a WebRTCDataChannels object.
     ~WebRTCDataChannels();
diff --git a/libraries/networking/src/webrtc/WebRTCSocket.cpp b/libraries/networking/src/webrtc/WebRTCSocket.cpp
index 2247ad8615..69b97ebf94 100644
--- a/libraries/networking/src/webrtc/WebRTCSocket.cpp
+++ b/libraries/networking/src/webrtc/WebRTCSocket.cpp
@@ -16,9 +16,9 @@
 #include "../udt/Constants.h"
 
 
-WebRTCSocket::WebRTCSocket(QObject* parent, NodeType_t nodeType) :
+WebRTCSocket::WebRTCSocket(QObject* parent) :
     QObject(parent),
-    _dataChannels(this, nodeType)
+    _dataChannels(this)
 {
     // Route signaling messages.
     connect(this, &WebRTCSocket::onSignalingMessage, &_dataChannels, &WebRTCDataChannels::onSignalingMessage);
diff --git a/libraries/networking/src/webrtc/WebRTCSocket.h b/libraries/networking/src/webrtc/WebRTCSocket.h
index 9a1d6442d7..8e429673e1 100644
--- a/libraries/networking/src/webrtc/WebRTCSocket.h
+++ b/libraries/networking/src/webrtc/WebRTCSocket.h
@@ -31,8 +31,7 @@ public:
 
     /// @brief Constructs a new WebRTCSocket object.
     /// @param parent Qt parent object.
-    /// @param nodeType The type of node that the WebRTCsocket object is being used in.
-    WebRTCSocket(QObject* parent, NodeType_t nodeType);
+    WebRTCSocket(QObject* parent);
 
 
     /// @brief Nominally sets the value of a socket option.

From 1605039929c6d88b616700c9e643d4ec5d05658b Mon Sep 17 00:00:00 2001
From: David Rowe <david@ctrlaltstudio.com>
Date: Sat, 21 Aug 2021 21:11:42 +1200
Subject: [PATCH 5/6] Tidying

---
 libraries/networking/src/BaseAssetScriptingInterface.cpp | 1 +
 libraries/networking/src/NetworkPeer.cpp                 | 2 +-
 libraries/networking/src/udt/NetworkSocket.h             | 2 +-
 3 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/libraries/networking/src/BaseAssetScriptingInterface.cpp b/libraries/networking/src/BaseAssetScriptingInterface.cpp
index f9dd12b279..872913082a 100644
--- a/libraries/networking/src/BaseAssetScriptingInterface.cpp
+++ b/libraries/networking/src/BaseAssetScriptingInterface.cpp
@@ -3,6 +3,7 @@
 //  libraries/networking/src
 //
 //  Copyright 2017 High Fidelity, Inc.
+//  Copyright 2021 Vircadia contributors.
 //
 //  Distributed under the Apache License, Version 2.0.
 //  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
diff --git a/libraries/networking/src/NetworkPeer.cpp b/libraries/networking/src/NetworkPeer.cpp
index e76b8c31a6..0b3b82ca65 100644
--- a/libraries/networking/src/NetworkPeer.cpp
+++ b/libraries/networking/src/NetworkPeer.cpp
@@ -117,7 +117,7 @@ void NetworkPeer::setActiveSocket(SockAddr* discoveredSocket) {
     // we have an active socket, stop our ping timer
     stopPingTimer();
 
-    // we're now considered connected to this peer - reset the number of connection attemps
+    // we're now considered connected to this peer - reset the number of connection attempts
     resetConnectionAttempts();
     
     if (_activeSocket) {
diff --git a/libraries/networking/src/udt/NetworkSocket.h b/libraries/networking/src/udt/NetworkSocket.h
index 2670fa40b8..887e73b32b 100644
--- a/libraries/networking/src/udt/NetworkSocket.h
+++ b/libraries/networking/src/udt/NetworkSocket.h
@@ -120,7 +120,7 @@ public:
 
 
 #if defined(WEBRTC_DATA_CHANNELS)
-    /// @brief  @brief Gets a pointer to the WebRTC socket object.
+    /// @brief Gets a pointer to the WebRTC socket object.
     /// @return A pointer to the WebRTC socket object.
     const WebRTCSocket* getWebRTCSocket();
 #endif

From adc94a280ec7a021d424f4475a71a37fe4835e1f Mon Sep 17 00:00:00 2001
From: David Rowe <david@ctrlaltstudio.com>
Date: Sun, 29 Aug 2021 14:19:39 +1200
Subject: [PATCH 6/6] Log some warnings

---
 assignment-client/src/AssignmentClient.cpp | 1 +
 domain-server/src/DomainServer.cpp         | 1 +
 2 files changed, 2 insertions(+)

diff --git a/assignment-client/src/AssignmentClient.cpp b/assignment-client/src/AssignmentClient.cpp
index cfe940133f..bd35c20df8 100644
--- a/assignment-client/src/AssignmentClient.cpp
+++ b/assignment-client/src/AssignmentClient.cpp
@@ -356,6 +356,7 @@ void AssignmentClient::handleWebRTCSignalingPacket(QSharedPointer<ReceivedMessag
         // Echo message back to sender.
 
         if (!json.keys().contains("to") || !json.keys().contains("from")) {
+            qCDebug(assignment_client) << "Invalid WebRTC signaling echo message received.";
             return;
         }
 
diff --git a/domain-server/src/DomainServer.cpp b/domain-server/src/DomainServer.cpp
index 569e662ae0..b844615c6d 100644
--- a/domain-server/src/DomainServer.cpp
+++ b/domain-server/src/DomainServer.cpp
@@ -901,6 +901,7 @@ void DomainServer::sendWebRTCSignalingMessageToAssignmentClient(const QJsonObjec
     auto limitedNodeList = DependencyManager::get<LimitedNodeList>();
     auto destinationNode = limitedNodeList->soloNodeOfType(destinationNodeType);
     if (!destinationNode) {
+        qWarning() << NodeType::getNodeTypeName(destinationNodeType) << "not found for WebRTC signaling message.";
         return;
     }
     // Use an NLPacketList because the signaling message is not necessarily small.