Certificate and token generation fixes

Summary:
A few things need to be done which are on this change:

- Certificate generation should execute as an atomic operation, hence, it needs to be synchronised.
- Do not generate client token as part of certificate generation. This causes a deadlock now.
- Add more logs for troubleshooting

Reviewed By: aigoncharov

Differential Revision: D49269624

fbshipit-source-id: 071a8e5b895198730b7d914cc4622837e9094e2f

desktop/flipper-server/src/index.tsx

@@ -235,6 +235,9 @@ async function start() {
     `[flipper-server][bootstrap] FlipperServer created (${serverCreatedMS} ms)`,
   );
 
+  // At this point, the HTTP server is ready and configuration is set.
+  await launch();
+
   const t6 = performance.now();
   const launchedMS = t6 - t5;
 
@@ -263,9 +266,6 @@ async function start() {
   }
   await flipperServer.connect();
 
-  // At this point, the HTTP server is ready and configuration is set.
-  await launch();
-
   const t8 = performance.now();
   const appServerStartedMS = t8 - t7;
   console.info(
@@ -309,6 +309,8 @@ async function launch() {
   console.info('[flipper-server] Launch UI');
   const token = await getAuthToken();
 
+  console.info('[flipper-server] Token is available: ' + token !== undefined);
+
   const searchParams = new URLSearchParams({token: token ?? ''});
   const url = new URL(`http://localhost:${argv.port}?${searchParams}`);