From 88213d8cfd248de750f53ec11feb30473818ac13 Mon Sep 17 00:00:00 2001
From: Eugene Crosser <crosser@average.org>
Date: Sat, 7 May 2022 00:05:21 +0200
Subject: [PATCH] support subscriptions on the client side

---
 gps303/wsgateway.py | 27 +++++++++++++++++++------
 webdemo/index.html  | 49 ++++++++++++++++++++++++++++++++++-----------
 2 files changed, 58 insertions(+), 18 deletions(-)

diff --git a/gps303/wsgateway.py b/gps303/wsgateway.py
index c7f9652..f2c6596 100644
--- a/gps303/wsgateway.py
+++ b/gps303/wsgateway.py
@@ -1,5 +1,6 @@
 """ Websocket Gateway """
 
+from json import loads
 from logging import getLogger
 from socket import socket, AF_INET6, SOCK_STREAM, SOL_SOCKET, SO_REUSEADDR
 from time import time
@@ -63,7 +64,7 @@ def try_http(data, fd, e):
                     return (
                         f"{proto} 500 File not found\r\n"
                         f"Content-Type: text/plain\r\n\r\n"
-                        f'HTML file could not be opened\r\n'.encode()
+                        f"HTML file could not be opened\r\n".encode()
                     )
             else:
                 return (
@@ -90,6 +91,8 @@ class Client:
         self.addr = addr
         self.ws = WSConnection(ConnectionType.SERVER)
         self.ws_data = b""
+        self.ready = False
+        self.imeis = set()
 
     def close(self):
         log.debug("Closing fd %d", self.sock.fileno())
@@ -122,6 +125,7 @@ class Client:
                 e,
             )
             self.ws_data = try_http(data, self.sock.fileno(), e)
+            self.write()  # TODO this is a hack
             log.debug("Sending HTTP response to %d", self.sock.fileno())
             msgs = None
         else:
@@ -131,25 +135,33 @@ class Client:
                     log.debug("WebSocket upgrade on fd %d", self.sock.fileno())
                     # self.ws_data += self.ws.send(event.response())  # Why not?!
                     self.ws_data += self.ws.send(AcceptConnection())
+                    self.ready = True
                 elif isinstance(event, (CloseConnection, Ping)):
                     log.debug("%s on fd %d", event, self.sock.fileno())
                     self.ws_data += self.ws.send(event.response())
                 elif isinstance(event, TextMessage):
                     # TODO: save imei "subscription"
                     log.debug("%s on fd %d", event, self.sock.fileno())
-                    msgs.append(event.data)
+                    msg = loads(event.data)
+                    msgs.append(msg)
+                    if msg.get("type", None) == "subscribe":
+                        self.imeis = set(msg.get("imei", []))
+                        log.debug(
+                            "subs list on fd %s is %s",
+                            self.sock.fileno(),
+                            self.imeis,
+                        )
                 else:
                     log.warning("%s on fd %d", event, self.sock.fileno())
-        if self.ws_data:  # Temp hack
-            self.write()
         return msgs
 
     def wants(self, imei):
+        log.debug("wants %s? set is %s on fd %d", imei, self.imeis, self.sock.fileno())
         return True  # TODO: check subscriptions
 
     def send(self, message):
-        # TODO: filter only wanted imei got from the client
-        self.ws_data += self.ws.send(Message(data=message.json))
+        if self.ready and message.imei in self.imeis:
+            self.ws_data += self.ws.send(Message(data=message.json))
 
     def write(self):
         if self.ws_data:
@@ -190,6 +202,7 @@ class Clients:
         result = []
         for msg in msgs:
             log.debug("Received: %s", msg)
+            result.append(msg)
         return result
 
     def send(self, msg):
@@ -250,9 +263,11 @@ def runserver(conf):
                     if received is None:
                         log.debug("Client gone from fd %d", sk)
                         tostop.append(sk)
+                        towait.discard(fd)
                     else:
                         for msg in received:
                             log.debug("Received from %d: %s", sk, msg)
+                        towrite.add(sk)
                 elif fl & zmq.POLLOUT:
                     log.debug("Write now open for fd %d", sk)
                     towrite.add(sk)
diff --git a/webdemo/index.html b/webdemo/index.html
index f356f96..2b3edd7 100644
--- a/webdemo/index.html
+++ b/webdemo/index.html
@@ -8,12 +8,20 @@
 	<script type="text/javascript">
 		const urlParams = new URLSearchParams(window.location.search);
 		const qimei = urlParams.get("imei");
-		const wsproto = window.protocol === "https" ? "wss" : "ws";
-		const wshost = window.hostname ? window.hostname : "localhost";
-		const wsport = window.port ? window.port : 5049;
+
+		const ourl = new URL(window.location);
+		const wsproto = ourl.protocol === "https" ? "wss" : "ws";
+		const wshost = ourl.hostname ? ourl.hostname : "localhost";
+		const wsport = ourl.port ? ourl.port : 5049;
+
+		const imeis = new Set();
 
 		var sts;
 		var ws;
+		var imei;
+		var send;
+		var subslist;
+		var tstamp;
 		var map;
 		var markers;
 		var icon;
@@ -24,6 +32,9 @@
 			sts.innerHTML = "uninitialized";
 			imei = document.getElementById("imei");
 			send = document.getElementById("send");
+			clear = document.getElementById("clear");
+			subslist = document.getElementById("subslist");
+			tstamp = document.getElementById("tstamp");
 			if (qimei) {
 				imei.value = qimei;
 			}
@@ -100,13 +111,13 @@
 			sts.innerHTML = "open";
 			imei.disabled = false;
 			send.disabled = false;
-			if (imei.value) {
-				sendIMEI();
-			}
+			clear.disabled = false;
+			sendIMEI();
 		}
 		function ws_onmessage(event) {
 			console.log("message " + event.data);
 			msg = JSON.parse(event.data)
+			tstamp.innerHTML = msg.devtime;
 			set_marker(+msg.longitude, +msg.latitude);
 		}
 		function ws_onerror(event) {
@@ -118,25 +129,35 @@
 			sts.innerHTML = "closed";
 			imei.disabled = true;
 			send.disabled = true;
+			clear.disabled = true;
 			setTimeout(open_ws, 5000);
 		}
 
-		function sendIMEI() {
-			console.log("sending " + imei.value);
+		function sendIMEI(do_clear) {
+			if (do_clear) {
+				imeis.clear();
+			} else {
+				if (imei.value) {
+					imeis.add(imei.value);
+				}
+			}
+			const imstr = Array.from(imeis).join(",");
+			document.title = imstr;
+			subslist.innerHTML = imstr;
 			var msg = {
-				imei: imei.value,
+				imei: Array.from(imeis),
 				type: "subscribe",
 				date: Date.now()
 			};
+			console.log("sending" + JSON.stringify(msg));
 			ws.send(JSON.stringify(msg));
-			document.title = imei.value;
 			imei.value = "";
 		}
 
 		function handleKey(evt) {
 			if (evt.keyCode === 13 || evt.keyCode === 14) {
 				if (!imei.disabled) {
-					sendIMEI();
+					sendIMEI(false);
 				}
 			}
 		}
@@ -149,7 +170,11 @@
 		 size="16" maxlength="16" placeholder="Enter IMEI"
 		 autocomplete="off" onkeyup="handleKey(event)">
 		<input type="button" id="send" name="send" value="Send"
-		 onclick="sendIMEI()" disabled>
+		 onclick="sendIMEI(false)" disabled>
+		<input type="button" id="clear" name="clear" value="Clear"
+		 onclick="sendIMEI(true)" disabled>
+		<span id="subslist"></span>
+		<span id="tstamp" style="float:right"></span>
 	</div>
 	<div style="width:100%; height:97%" id="map"></div>
 	<div style="width:100%; height:1%" id="sts"></div>
-- 
2.39.2