fix shared worker issue on restart and removed build files

.gitignore

@@ -2,10 +2,10 @@
 .DS_Store
 devsync.json
 /devsync
-public/dist
-public/css/*
-!public/css/reset.css
-!public/css/style.css
+web/dist
+web/css/*
+!web/css/reset.css
+!web/css/style.css
 node_modules
 yarn.lock
 /vendor

web/shared_worker.js

@@ -2,46 +2,54 @@
 let ports = [];
 let debug = false
 let EventSourceSingleton = (function () {
-    var instance = null;
-    return {
-        getInstance: function (sse_url) {
-            if (!instance) {
-                instance = new EventSource(sse_url);
-            }
-            return instance;
-        }
-    };
+	var instance = null;
+	return {
+		getInstance: function (sse_url) {
+			if (!instance) {
+				instance = new EventSource(sse_url);
+			}
+			return instance;
+		},
+		reset: function () {
+			instance = null;
+		}
+	};
 })();
 
 
+// https://developer.mozilla.org/en-US/docs/Web/API/SharedWorkerGlobalScope/onconnect
 onconnect = function(e) {
 	console.log('worker connected');
 	var port = e.ports[0];
 	ports.push(port);
-    var notifyAll = function(message){
-        ports.forEach(port => port.postMessage(message));
-    }
+	var notifyAll = function(message){
+		ports.forEach(port => port.postMessage(message));
+	}
 	var makeConnection = function (sse_url) {
-        var source = EventSourceSingleton.getInstance(sse_url);
-        source.onopen = function (e){
-			console.log(e)
-            var message = "Connection open"
-            port.postMessage({type: 'open' , msg: 'Connection opened !'});
-        }
-        source.onerror = function(e){
-			console.log(e)
-            port.postMessage({type: 'error' , msg: 'error connecting to server'});
-            source.close()
-        }
-        source.onmessage = function(e){
-			console.log(e)
-            notifyAll({type: 'message' , msg: e.data});
-        }
-    }
+		var source = EventSourceSingleton.getInstance(sse_url);
+		source.onopen = function (e){
+			console.log(e);
+			port.postMessage({type: 'open' , msg: 'Connection opened !'});
+		}
+		source.onerror = function(e){
+			console.log(e);
+			port.postMessage({type: 'error' , msg: 'error connecting to server'});
+			// on server disconnect, we close the connection and reset singleton
+			// or as long as there are old pages with connection active, any new connection after restart won't work
+			source.close();
+			EventSourceSingleton.reset();
+			ports.forEach(p => p.close());
+		}
+		source.onmessage = function(e){
+			console.log(e);
+			notifyAll({type: 'message' , msg: e.data});
+		}
+	}
 
-    port.onmessage = function(e) {
+	port.onmessage = function(e) {
 		console.log('received init message, making connection...')
-        makeConnection(e.data);
-    }
-    port.start(); // Required when using addEventListener. Otherwise called implicitly by onmessage setter.
+		makeConnection(e.data);
+	}
+	port.start(); // Required when using addEventListener. Otherwise called implicitly by onmessage setter.
+
 }