feat: add backend

src/cli.ts

@@ -0,0 +1,93 @@
+/*
+ * Copyright (C) 2019 StApps
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+import * as http from 'http';
+import { app } from './app';
+import { logger } from './common';
+
+/**
+ * Get port from environment and store in Express.
+ */
+const port = normalizePort(process.env.PORT || '3000');
+app.set('port', port);
+
+/**
+ * Create HTTP server.
+ */
+const server = http.createServer(app);
+
+/**
+ * Listen on provided port, on all network interfaces.
+ */
+server.listen(port);
+server.on('error', onError);
+server.on('listening', onListening);
+
+/**
+ * Normalize a port into a number, string, or false.
+ */
+function normalizePort(value: string) {
+  const portNumber = parseInt(value, 10);
+
+  if (isNaN(portNumber)) {
+    // named pipe
+    return value;
+  }
+
+  if (portNumber >= 0) {
+    // port number
+    return portNumber;
+  }
+
+  return false;
+}
+
+/**
+ * Event listener for HTTP server "error" event.
+ */
+function onError(error: Error | any) {
+  if (error.syscall !== 'listen') {
+    throw error;
+  }
+
+  const bind = typeof port === 'string'
+    ? 'Pipe ' + port
+    : 'Port ' + port;
+
+  // handle specific listen errors with friendly messages
+  switch (error.code) {
+    case 'EACCES':
+      logger.error(bind + ' requires elevated privileges');
+      process.exit(1);
+      break;
+    case 'EADDRINUSE':
+      logger.error(bind + ' is already in use');
+      process.exit(1);
+      break;
+    default:
+      throw error;
+  }
+}
+
+/**
+ * Event listener for HTTP server "listening" event.
+ */
+function onListening() {
+  const addr = server.address();
+  const bind = typeof addr === 'string'
+    ? 'pipe ' + addr
+    : 'port ' + addr.port;
+  logger.ok('Listening on ' + bind);
+}