1 files changed, 70 insertions, 0 deletions
diff --git a/backend/instance/api-connection.ts b/backend/instance/api-connection.ts
new file mode 100644
index 0000000..3f0a661
--- /dev/null
+++ b/backend/instance/api-connection.ts
@@ -0,0 +1,70 @@
+import { WebSocket as wsocket } from 'ws';
+import { ServerStatus as Status } from './api-defs.js';
+
+let SERVER_LOG = 1;
+let API_ADDRESS = 'http://localhost:4000';
+
+export var status: Status = { isBusy: false, lastUpdate: 0, loadedModel: '', domain: '' };
+export var ws: wsocket;
+
+let slog = ( msg: string ) => { if( SERVER_LOG ) console.log( '[server] ' + msg ); };
+
+export function setStatus( s: any ) {
+  const newstatus: Status = { ...status, ...s };
+  status = newstatus;
+  return status;
+}
+
+export function serverOpen( addr: string ) {
+  API_ADDRESS = addr;
+  ws = new wsocket( addr );
+
+  ws.on( 'open', () => {
+    slog( 'connection opened' );
+    let s = status;
+    s.lastUpdate = Date.now();
+    s.msg = 'welcome';
+    ws.send( JSON.stringify( s ) );
+  } );
+
+  ws.on( 'message', ( message: string ) => {
+    status.lastUpdate = Date.now();
+    try {
+      let json = JSON.parse( message );
+      if( json.msg == 'ping' ) {
+        let s = { ...status };
+        s.msg = 'pong';
+        setTimeout( () => ws.send( JSON.stringify( s ) ), 5000 );
+      }
+      else {
+        slog( `unhandled message: ${message}` );
+      }
+    } catch ( err ) {
+      slog( '[server] ' + err );
+    }
+  } );
+
+  ws.on( 'error' , ( err ) => {
+    slog( `WebSocket error: ${err}` );
+    ws.close();
+  } );
+
+  ws.on( 'close', ( code, reason ) => {
+    setTimeout( () => { ws = serverOpen( addr ) }, 5000 );
+    slog( `connection closed: ${code}, ${reason}` );
+  } );
+
+  return ws;
+};
+
+export function serverNotify( what: any ) {
+  const newstatus: Status = { ...status, ...what };
+  status = newstatus;
+  try {
+    ws.send( JSON.stringify( status ) );
+  }
+  catch ( err ) {
+    slog( '[server] ' + err );
+    ws = serverOpen( API_ADDRESS );
+  }
+};