Wait for confirmation that server is online before opening browser

scripts/run_server.py

 import argparse
 from multiprocessing import Process
+import requests
 import uvicorn
 import webbrowser
 
@@ -42,10 +43,18 @@ if __name__ == '__main__':
         },
         daemon=True,
     )
-    server_process.start()
-
     url = f'http://{args.host}:{int(args.port):04d}/status'
     print(url)
+    server_process.start()
+
+    try:
+        resp = requests.get(url)
+        assert resp.status_code == 200
+    except Exception:
+        print('Error starting server')
+        server_process.terminate()
+        exit()
+
     webbrowser.open(url, new=1, autoraise=True)
 
     if args.debug: