Language Server restarts only once in case of failure in Visual Studio

Question

I am working on an extension that has a Language Server (LSP) implemented. I am trying to load the language server again in case of failure calling - ILanguageClientBroker.LoadAsync

This works fine once, Language Server is loaded again once.

But again if Language Server process exits and I try to load again calling ILanguageClientBroker.LoadAsync, this does not work. ILanguageClient.ActivateAsync is not getting called the second time on.

Does Visual Studio restrict retry attempts to load Langauge Server to only once ?

Is there a way to change the retry attempt to say 5 times ?

Answer 1

Thanks for reaching out!

Retry restarting the Language Server in Visual Studio Extension up to 5 times

1. Unregister the language server on failure, when the LSP process crashes/exits, call:

await LanguageClientBroker.StopAsync();

This clears the previous registration so it can restart again.

2. Add retry logic, use a loop to retry loading the server:

int maxRetries = 5;

int retryCount = 0;

while (retryCount < maxRetries)

{

    try

    {

        await LanguageClientBroker.LoadAsync();

        break; // exit loop if success

    }

    catch

    {

        retryCount++;

        await Task.Delay(2000); // wait 2 seconds before retry

    }

}

3. Ensure ActivateAsync gets triggered every restart and before each retry, reset the client:

LanguageClientBroker.Dispose();

4. Restart Visual Studio services if still failing

Tools and next Command Palette and select "Developer: Reload Window"

5. If server still doesn't load after 5 retries

• Close Visual Studio,
• Delete .vs folder in the project
• Reopen Visual Studio

This removes cached LSP state.