protocol: Rework the way peers set their status

- Remove registration messages
- Add a setPeerStatus method which lets other peers know about their roles

plugins/src/signaller/imp.rs

@@ -105,10 +105,11 @@ impl Signaller {
         } else {
             None
         };
-
         websocket_sender
-            .send(p::IncomingMessage::Register(p::RegisterMessage::Producer {
+            .send(p::IncomingMessage::SetPeerStatus(p::PeerStatus {
+                roles: vec![p::PeerRole::Producer],
                 meta,
+                peer_id: None,
             }))
             .await?;
 
@@ -122,10 +123,7 @@ impl Signaller {
 
                             if let Ok(msg) = serde_json::from_str::<p::OutgoingMessage>(&msg) {
                                 match msg {
-                                    p::OutgoingMessage::Welcome { .. } => (),
-                                    p::OutgoingMessage::Registered(
-                                        p::RegisteredMessage::Producer { peer_id, .. },
-                                    ) => {
+                                    p::OutgoingMessage::Welcome { peer_id } => {
                                         gst::info!(
                                             CAT,
                                             obj: &element,
@@ -133,7 +131,6 @@ impl Signaller {
                                             peer_id
                                         );
                                     }
-                                    p::OutgoingMessage::Registered(_) => unreachable!(),
                                     p::OutgoingMessage::StartSession {
                                         session_id,
                                         peer_id,

protocol/src/lib.rs

@@ -1,62 +1,6 @@
 /// The default protocol used by the signalling server
 use serde::{Deserialize, Serialize};
 
-#[derive(Serialize, Deserialize, Debug, PartialEq)]
-#[serde(tag = "peerType")]
-#[serde(rename_all = "camelCase")]
-/// Confirms registration
-pub enum RegisteredMessage {
-    /// Registered as a producer
-    #[serde(rename_all = "camelCase")]
-    Producer {
-        peer_id: String,
-        #[serde(default)]
-        meta: Option<serde_json::Value>,
-    },
-    /// Registered as a consumer
-    #[serde(rename_all = "camelCase")]
-    Consumer {
-        peer_id: String,
-        #[serde(default)]
-        meta: Option<serde_json::Value>,
-    },
-    /// Registered as a listener
-    #[serde(rename_all = "camelCase")]
-    Listener {
-        peer_id: String,
-        #[serde(default)]
-        meta: Option<serde_json::Value>,
-    },
-}
-
-#[derive(Serialize, Deserialize, Debug, PartialEq, Clone)]
-#[serde(tag = "peerType")]
-#[serde(rename_all = "camelCase")]
-/// Confirms registration
-pub enum UnregisteredMessage {
-    /// Unregistered as a producer
-    #[serde(rename_all = "camelCase")]
-    Producer {
-        peer_id: String,
-        #[serde(default)]
-        meta: Option<serde_json::Value>,
-    },
-    /// Unregistered as a consumer
-    #[serde(rename_all = "camelCase")]
-    Consumer {
-        peer_id: String,
-        #[serde(default)]
-        meta: Option<serde_json::Value>,
-    },
-    /// Unregistered as a listener
-    #[serde(rename_all = "camelCase")]
-    Listener {
-        peer_id: String,
-        #[serde(default)]
-        meta: Option<serde_json::Value>,
-    },
-}
-
 #[derive(Serialize, Deserialize, Debug, PartialEq)]
 #[serde(rename_all = "camelCase")]
 pub struct Peer {
@@ -72,32 +16,14 @@ pub struct Peer {
 pub enum OutgoingMessage {
     /// Welcoming message, sets the Peer ID linked to a new connection
     Welcome { peer_id: String },
-    /// Confirms registration
-    Registered(RegisteredMessage),
-    /// Confirms registration
-    Unregistered(UnregisteredMessage),
-    /// Notifies listeners that a producer was registered
-    #[serde(rename_all = "camelCase")]
-    ProducerAdded {
-        peer_id: String,
-        #[serde(default)]
-        meta: Option<serde_json::Value>,
-    },
-    /// Notifies listeners that a producer was removed
-    #[serde(rename_all = "camelCase")]
-    ProducerRemoved {
-        peer_id: String,
-        #[serde(default)]
-        meta: Option<serde_json::Value>,
-    },
+    /// Notifies listeners that a peer status has changed
+    PeerStatusChanged(PeerStatus),
     /// Instructs a peer to generate an offer and inform about the session ID
     #[serde(rename_all = "camelCase")]
     StartSession { peer_id: String, session_id: String },
-
     /// Let consumer know that the requested session is starting with the specified identifier
     #[serde(rename_all = "camelCase")]
     SessionStarted { peer_id: String, session_id: String },
-
     /// Signals that the session the peer was in was ended
     #[serde(rename_all = "camelCase")]
     EndSession(EndSessionMessage),
@@ -109,45 +35,36 @@ pub enum OutgoingMessage {
     Error { details: String },
 }
 
-#[derive(Serialize, Deserialize, Debug)]
-#[serde(tag = "peerType")]
+#[derive(Serialize, Deserialize, Debug, PartialEq, Eq, Clone)]
 #[serde(rename_all = "camelCase")]
 /// Register with a peer type
-pub enum RegisterMessage {
+pub enum PeerRole {
     /// Register as a producer
     #[serde(rename_all = "camelCase")]
-    Producer {
-        #[serde(default)]
-        meta: Option<serde_json::Value>,
-    },
-    /// Register as a consumer
-    #[serde(rename_all = "camelCase")]
-    Consumer {
-        #[serde(default)]
-        meta: Option<serde_json::Value>,
-    },
+    Producer,
     /// Register as a listener
     #[serde(rename_all = "camelCase")]
-    Listener {
-        #[serde(default)]
-        meta: Option<serde_json::Value>,
-    },
+    Listener,
 }
 
-#[derive(Serialize, Deserialize, Debug)]
-#[serde(tag = "peerType")]
+#[derive(Serialize, Deserialize, Debug, PartialEq, Eq, Default, Clone)]
 #[serde(rename_all = "camelCase")]
-/// Register with a peer type
-pub enum UnregisterMessage {
-    /// Unregister a producer
-    #[serde(rename_all = "camelCase")]
-    Producer,
-    /// Unregister a consumer
-    #[serde(rename_all = "camelCase")]
-    Consumer,
-    /// Unregister a listener
-    #[serde(rename_all = "camelCase")]
-    Listener,
+pub struct PeerStatus {
+    pub roles: Vec<PeerRole>,
+    pub meta: Option<serde_json::Value>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    #[serde(default)]
+    pub peer_id: Option<String>,
+}
+
+impl PeerStatus {
+    pub fn producing(&self) -> bool {
+        self.roles.iter().any(|t| matches!(t, PeerRole::Producer))
+    }
+
+    pub fn listening(&self) -> bool {
+        self.roles.iter().any(|t| matches!(t, PeerRole::Listener))
+    }
 }
 
 #[derive(Serialize, Deserialize, Debug)]
@@ -212,12 +129,10 @@ pub struct EndSessionMessage {
 #[serde(rename_all = "camelCase")]
 /// Messages received by the server from peers
 pub enum IncomingMessage {
-    /// Register as a peer type
+    /// Internal message to let know about new peers
     NewPeer,
-    /// Register as a peer type
-    Register(RegisterMessage),
-    /// Unregister as a peer type
-    Unregister(UnregisterMessage),
+    /// Set current peer status
+    SetPeerStatus(PeerStatus),
     /// Start a session with a producer peer
     StartSession(StartSessionMessage),
     /// End an existing session

signalling/src/server/mod.rs

@@ -172,7 +172,6 @@ impl Server {
                     warn!(this = %this_id_clone, "Error handling message: {:?}", err);
                 }
             }
-
             while let Some(msg) = ws_stream.next().await {
                 info!("Received message {msg:?}");
                 match msg {

www/webrtc.js

@@ -385,16 +385,15 @@ function onServerMessage(event) {
         msg = JSON.parse(event.data);
     } catch (e) {
         if (e instanceof SyntaxError) {
-            this.handleIncomingError("Error parsing incoming JSON: " + event.data);
+            console.error("Error parsing incoming JSON: " + event.data);
         } else {
-            this.handleIncomingError("Unknown error parsing response: " + event.data);
+            console.error("Unknown error parsing response: " + event.data);
         }
         return;
     }
 
     if (msg.type == "welcome") {
         console.info(`Got welcomed with ID ${msg.peer_id}`);
-    } else if (msg.type == "registered") {
         ws_conn.send(JSON.stringify({
             "type": "list"
         }));
@@ -403,13 +402,18 @@ function onServerMessage(event) {
         for (i = 0; i < msg.producers.length; i++) {
             addPeer(msg.producers[i].id, msg.producers[i].meta);
         }
-    } else if (msg.type == "producerAdded") {
-        addPeer(msg.peerId, msg.meta);
-    } else if (msg.type == "producerRemoved") {
+    } else if (msg.type == "peerStatusChanged") {
         var li = document.getElementById("peer-" + msg.peerId);
-        li.parentNode.removeChild(li);
+        if (msg.roles.includes("producer")) {
+            if (li == null) {
+                console.error('Adding peer');
+                addPeer(msg.peerId, msg.meta);
+            }
+        } else if (li != null) {
+            li.parentNode.removeChild(li);
+        }
     } else {
-        this.handleIncomingError("Unsupported message: ", msg);
+        console.error("Unsupported message: ", msg);
     }
 };
 
@@ -448,8 +452,8 @@ function connect() {
     ws_conn = new WebSocket(ws_url);
     ws_conn.addEventListener('open', (event) => {
         ws_conn.send(JSON.stringify({
-            "type": "register",
-            "peerType": "listener"
+            "type": "setPeerStatus",
+            "roles": ["listener"]
         }));
     });
     ws_conn.addEventListener('error', onServerError);