1 files changed, 47 insertions, 0 deletions

diff --git a/src/electron/ipc-api/localServer.ts b/src/electron/ipc-api/localServer.ts
new file mode 100644
index 000000000..d318b93a5
--- /dev/null
+++ b/src/electron/ipc-api/localServer.ts
@@ -0,0 +1,47 @@
+import { ipcMain, BrowserWindow } from 'electron';
+import net from 'net';
+import { LOCAL_HOSTNAME, LOCAL_PORT } from '../../config';
+import { userDataPath } from '../../environment';
+import startServer from '../../internal-server/start';
+
+const portInUse = (port: number): Promise<boolean> =>
+  new Promise(resolve => {
+    const server = net.createServer(socket => {
+      socket.write('Echo server\r\n');
+      socket.pipe(socket);
+    });
+
+    server.listen(port, LOCAL_HOSTNAME);
+    server.on('error', () => {
+      resolve(true);
+    });
+    server.on('listening', () => {
+      server.close();
+      resolve(false);
+    });
+  });
+
+let localServerStarted = false;
+
+export default (params: { mainWindow: BrowserWindow }) => {
+  ipcMain.on('startLocalServer', () => {
+    if (!localServerStarted) {
+      // Find next unused port for server
+      let port = LOCAL_PORT;
+      (async () => {
+        // eslint-disable-next-line no-await-in-loop
+        while ((await portInUse(port)) && port < LOCAL_PORT + 10) {
+          port += 1;
+        }
+        console.log('Starting local server on port', port);
+
+        startServer(userDataPath(), port);
+
+        params.mainWindow.webContents.send('localServerPort', {
+          port,
+        });
+      })();
+      localServerStarted = true;
+    }
+  });
+};