Add WebSocket server

clapper_src/webserver.js

@@ -0,0 +1,158 @@
+const { Soup, GObject } = imports.gi;
+const ByteArray = imports.byteArray;
+const Debug = imports.clapper_src.debug;
+
+let { debug } = Debug;
+
+var WebServer = GObject.registerClass({
+    Signals: {
+        'websocket-data': {
+            flags: GObject.SignalFlags.RUN_FIRST,
+            param_types: [
+                GObject.TYPE_STRING,
+                GObject.TYPE_INT || GObject.TYPE_STRING
+            ]
+        }
+    }
+}, class ClapperWebServer extends Soup.Server
+{
+    _init(port)
+    {
+        super._init();
+
+        this.isListening = false;
+        this.listeningPort = null;
+        this.wsConns = [];
+
+        if(port)
+            this.setListeningPort(port);
+    }
+
+    setListeningPort(port)
+    {
+        if(!port)
+            return;
+
+        const wasListening = this.isListening;
+
+        if(wasListening)
+            this.stopListening();
+
+        this.listeningPort = port;
+
+        if(wasListening)
+            this.startListening();
+    }
+
+    startListening()
+    {
+        if(this.isListening || !this.listeningPort)
+            return;
+
+        let isListening = false;
+
+        this.add_handler('/', this._onDefaultAccess.bind(this));
+        this.add_websocket_handler('/websocket', null, null, this._onWsConnection.bind(this));
+
+        try {
+            isListening = this.listen_local(this.listeningPort, Soup.ServerListenOptions.IPV4_ONLY);
+        }
+        catch(err) {
+            debug(err);
+        }
+
+        if(isListening) {
+            const uris = this.get_uris();
+            const usedPort = uris[0].get_port();
+            debug(`WebSocket server listening on port: ${usedPort}`);
+        }
+        else {
+            debug(new Error('WebSocket server could not start listening'));
+            this._closeCleanup();
+        }
+
+        this.isListening = isListening;
+    }
+
+    stopListening()
+    {
+        if(!this.isListening)
+            return;
+
+        this._closeCleanup();
+        this.disconnect();
+
+        this.isListening = false;
+        this.listeningPort = null;
+    }
+
+    sendMessage(data)
+    {
+        for(const connection of this.wsConns) {
+            if(connection.state !== Soup.WebsocketState.OPEN)
+                continue;
+
+            connection.send_text(JSON.stringify(data));
+        }
+    }
+
+    _closeCleanup()
+    {
+        while(this.wsConns.length) {
+            const connection = this.wsConns.pop();
+
+            if(connection.state !== Soup.WebsocketState.OPEN)
+                continue;
+
+            connection.close(Soup.WebsocketCloseCode.NORMAL, null);
+        }
+
+        this.remove_handler('/websocket');
+        this.remove_handler('/');
+    }
+
+    _onWsConnection(server, connection)
+    {
+        debug('new WebSocket connection');
+
+        connection.connect('message', this._onWsMessage.bind(this));
+        connection.connect('closed', this._onWsClosed.bind(this));
+
+        this.wsConns.push(connection);
+        debug(`total WebSocket connections: ${this.wsConns.length}`);
+    }
+
+    _onWsMessage(connection, dataType, bytes)
+    {
+        if(dataType !== Soup.WebsocketDataType.TEXT)
+            return debug('ignoring non-text WebSocket message');
+
+        const msg = bytes.get_data();
+        let parsedMsg = null;
+
+        try {
+            parsedMsg = JSON.parse(ByteArray.toString(msg));
+        }
+        catch(err) {
+            debug(err);
+        }
+
+        if(!parsedMsg || !parsedMsg.action)
+            return debug('no "action" in parsed WebSocket message');
+
+        this.emit('websocket-data', parsedMsg.action, parsedMsg.value || 0);
+    }
+
+    _onWsClosed(connection)
+    {
+        debug('closed WebSocket connection');
+
+        this.wsConns = this.wsConns.filter(conn => conn !== connection);
+        debug(`remaining WebSocket connections: ${this.wsConns.length}`);
+    }
+
+    _onDefaultAccess(server, msg)
+    {
+        msg.status_code = 404;
+    }
+});