[Socket] send connect error to client and close

assets/js/phoenix/socket.js

@@ -530,6 +530,10 @@ export default class Socket {
 
       if(this.hasLogger()) this.log("receive", `${payload.status || ""} ${topic} ${event} ${ref && "(" + ref + ")" || ""}`, payload)
 
+      if (topic === 'phoenix') {
+        this.onPhoenixMessage(event, payload, ref, join_ref)
+      }
+
       for(let i = 0; i < this.channels.length; i++){
         const channel = this.channels[i]
         if(!channel.isMember(topic, event, payload, join_ref)){ continue }
@@ -543,6 +547,12 @@ export default class Socket {
     })
   }
 
+  onPhoenixMessage(event, payload, ref, join_ref) {
+    if (event === 'phx_error') {
+      this.onConnError(payload)
+    }
+  }
+
   leaveOpenTopic(topic){
     let dupChannel = this.channels.find(c => c.topic === topic && (c.isJoined() || c.isJoining()))
     if(dupChannel){

lib/phoenix/endpoint/cowboy2_handler.ex

@@ -44,8 +44,8 @@ defmodule Phoenix.Endpoint.Cowboy2Handler do
 
               {:cowboy_websocket, copy_resp_headers(conn, req), [handler | state], cowboy_opts}
 
-            {:error, %Plug.Conn{adapter: {@connection, req}} = conn} ->
-              {:ok, copy_resp_headers(conn, req), {handler, opts}}
+            {:error, reason, %Plug.Conn{adapter: {@connection, req}} = conn} ->
+              {:cowboy_websocket, copy_resp_headers(conn, req), [{:error, reason}, handler]}
           end
 
         {:plug, conn, handler, opts} ->
@@ -136,6 +136,15 @@ defmodule Phoenix.Endpoint.Cowboy2Handler do
 
   ## Websocket callbacks
 
+  def websocket_init([{:error, reason}, handler]) do
+    last_frame = Jason.encode!([nil, nil, "phoenix", "phx_error", reason])
+    # Close frame payloads have a max size of 123 bytes
+    {[
+      {:text, last_frame},
+      {:close, 3000, ""}
+      ], [handler]}
+  end
+
   def websocket_init([handler | state]) do
     {:ok, state} = handler.init(state)
     {:ok, [handler | state]}

lib/phoenix/transports/websocket.ex

@@ -32,10 +32,9 @@ defmodule Phoenix.Transports.WebSocket do
 
         case handler.connect(config) do
           {:ok, state} -> {:ok, conn, state}
-          :error -> {:error, Plug.Conn.send_resp(conn, 403, "")}
+          :error -> {:error, :unknown, conn}
           {:error, reason} ->
-            {m, f, args} = opts[:error_handler]
-            {:error, apply(m, f, [conn, reason | args])}
+            {:error, reason, conn}
         end
     end
   end

priv/static/phoenix.js

@@ -1099,6 +1099,9 @@ var Phoenix = (() => {
         }
         if (this.hasLogger())
           this.log("receive", `${payload.status || ""} ${topic} ${event} ${ref && "(" + ref + ")" || ""}`, payload);
+        if (topic === "phoenix") {
+          this.onPhoenixMessage(event, payload, ref, join_ref);
+        }
         for (let i = 0; i < this.channels.length; i++) {
           const channel = this.channels[i];
           if (!channel.isMember(topic, event, payload, join_ref)) {
@@ -1112,6 +1115,11 @@ var Phoenix = (() => {
         }
       });
     }
+    onPhoenixMessage(event, payload, ref, join_ref) {
+      if (event === "phx_error") {
+        this.onConnError(payload);
+      }
+    }
     leaveOpenTopic(topic) {
       let dupChannel = this.channels.find((c) => c.topic === topic && (c.isJoined() || c.isJoining()));
       if (dupChannel) {

priv/static/phoenix.mjs

@@ -1070,6 +1070,9 @@ var Socket = class {
       }
       if (this.hasLogger())
         this.log("receive", `${payload.status || ""} ${topic} ${event} ${ref && "(" + ref + ")" || ""}`, payload);
+      if (topic === "phoenix") {
+        this.onPhoenixMessage(event, payload, ref, join_ref);
+      }
       for (let i = 0; i < this.channels.length; i++) {
         const channel = this.channels[i];
         if (!channel.isMember(topic, event, payload, join_ref)) {
@@ -1083,6 +1086,11 @@ var Socket = class {
       }
     });
   }
+  onPhoenixMessage(event, payload, ref, join_ref) {
+    if (event === "phx_error") {
+      this.onConnError(payload);
+    }
+  }
   leaveOpenTopic(topic) {
     let dupChannel = this.channels.find((c) => c.topic === topic && (c.isJoined() || c.isJoining()));
     if (dupChannel) {