Use new on_timer solution, to check every 1 second, the presence of ".stop" file.

If this file exists, close all active websockets.

Redesigned the commands implementation for this example.

examples/websocket/application_execution.e

@@ -10,6 +10,9 @@ inherit
 	WSF_WEBSOCKET_EXECUTION
 
 	WEB_SOCKET_EVENT_I
+		redefine
+			on_timer
+		end
 
 create
 	make
@@ -52,6 +55,9 @@ feature -- Websocket execution
 
 	on_open (ws: WEB_SOCKET)
 		do
+			initialize_commands
+			set_timer_delay (1) -- Every 1 second.
+
 			ws.put_error ("Connecting")
 			ws.send (Text_frame, "Hello, this is a simple demo with Websocket using Eiffel. (/help for more information).%N")
 		end
@@ -62,12 +68,26 @@ feature -- Websocket execution
 		end
 
 	on_text (ws: WEB_SOCKET; a_message: READABLE_STRING_8)
+		local
+			i: INTEGER
+			cmd_name: READABLE_STRING_8
 		do
-			if a_message.same_string_general ("/help") then
-					-- Echo the message for testing.
-				ws.send (Text_frame, "Help: available commands%N  - /time : return the server UTC time.%N")
-			elseif a_message.starts_with_general ("/time") then
-				ws.send (Text_frame, "Server time is " + (create {HTTP_DATE}.make_now_utc).string)
+			if a_message.starts_with_general ("/") then
+				from
+					i := 1
+				until
+					i >= a_message.count or else a_message[i + 1].is_space
+				loop
+					i := i + 1
+				end
+				cmd_name := a_message.substring (2, i)
+				if attached command (cmd_name) as cmd then
+					cmd (ws, a_message.substring (i + 1, a_message.count))
+				elseif a_message.same_string_general ("/help") then
+					on_help_command (ws, Void)
+				else
+					ws.send (Text_frame, "Error: unknown command '/" + cmd_name + "'!%N")
+				end
 			else
 					-- Echo the message for testing.
 				ws.send (Text_frame, a_message)
@@ -80,6 +100,88 @@ feature -- Websocket execution
 			ws.put_error ("Connection closed")
 		end
 
+	on_timer (ws: WEB_SOCKET)
+			-- <Precursor>.
+			-- If ever the file ".stop" exists, stop gracefully the connection.
+		local
+			fut: FILE_UTILITIES
+			f: RAW_FILE
+		do
+			if fut.file_exists (".stop") then
+				ws.send_text ("End of the communication ...%N")
+				ws.send_connection_close ("")
+				create f.make_with_name (".stop")
+				f.delete
+			end
+		end
+
+feature -- Command
+
+	initialize_commands
+		do
+			register_command (agent on_help_command, "help", "Display this help.")
+			register_command (agent on_time_command, "time", "Return the server UTC time.")
+			register_command (agent on_shutdown_command, "shutdown", "Shutdown the service (ends the websocket).")
+		end
+
+	register_command (a_cmd: attached like command; a_name: READABLE_STRING_8; a_description: READABLE_STRING_8)
+		local
+			tb: like commands
+		do
+			tb := commands
+			if tb = Void then
+				create tb.make_caseless (1)
+				commands := tb
+			end
+			tb.force ([a_cmd, a_name, a_description], a_name)
+		end
+
+	commands: detachable STRING_TABLE [TUPLE [cmd: attached like command; name, description: READABLE_STRING_8]]
+
+	command (a_name: READABLE_STRING_GENERAL): detachable PROCEDURE [TUPLE [ws: WEB_SOCKET; args: detachable READABLE_STRING_GENERAL]]
+		do
+			if
+				attached commands as tb and then
+				attached tb.item (a_name) as d
+			then
+				Result := d.cmd
+			end
+		end
+
+	on_help_command (ws: WEB_SOCKET; args: detachable READABLE_STRING_GENERAL)
+		local
+			s: STRING
+		do
+			create s.make_from_string ("Help: available commands:%N")
+			if attached commands as tb then
+				across
+					tb as ic
+				loop
+					s.append ("<li> /")
+					s.append (ic.item.name)
+					s.append (" : ")
+					s.append (ic.item.description)
+					s.append ("</li>%N")
+				end
+			end
+			ws.send_text (s)
+		end
+
+	on_time_command (ws: WEB_SOCKET; args: detachable READABLE_STRING_GENERAL)
+		do
+			ws.send_text ("Server time is " + (create {HTTP_DATE}.make_now_utc).string)
+		end
+
+	on_shutdown_command (ws: WEB_SOCKET; args: detachable READABLE_STRING_GENERAL)
+		local
+			f: RAW_FILE
+		do
+			ws.send_text ("Active websockets will end soon.%N")
+			create f.make_create_read_write (".stop")
+			f.put_string ("stop%N")
+			f.close
+		end
+
 feature -- HTML Resource				
 
 	websocket_app_html (a_port: INTEGER): STRING
@@ -188,5 +290,4 @@ body {font-family:Arial, Helvetica, sans-serif;}
 			end
 		end
 
-
 end