review all the request handlers and make sure nothing is running directly on the main thread.

[alanrenmsft]

No description provided.

[alanrenmsft]

https://github.com/microsoft/sqltoolsservice/blob/main/src/Microsoft.SqlTools.ServiceLayer/Agent/AgentService.cs#L151 is blocking

[Charles-Gagnon]

So @alanrenmsft the concern I had with just returning TaskCompleted for that instance was I just want us to make sure that we're ok with having each message handler determine whether they're blocking or non-blocking and to need to do that by spinning off a separate thread and then just returning immediately. Right now all messages are blocking which I'm not sure is really made clear anywhere so mistakes like this can happen. Might be worth looking at a couple of other options :

1. Make messages non-blocking by default. I'm not even sure why message handlers are blocking in the first place - are there any scenarios that we need that which isn't just solved by the fact that on the calling side it needs to wait for a response to be sent anyways
2. Have some sort of flag to the set handler method that tells it whether to be blocking or not - just to make it more clear