Trying to start a workflow from asp.net and the client hangs

What are you really trying to do?

Trying to start a workflow from asp.net minimal api.

Describe the bug

If I create the client at startup, and then try and use that client instance within an endpoint it hangs when I call StartWorkflowAsync.

If I create a client within the MapGet endpoint lambda it works.

Minimal Reproduction

using Temporalio.Client;
using Temporalio.Runtime;

var builder = WebApplication.CreateBuilder(args);

builder.Logging.AddSimpleConsole(options =>
{
    options.TimestampFormat = "yyyy-mm-ddTHH:mm:ss.ff ";
    options.UseUtcTimestamp = true;
    options.IncludeScopes = false;
    options.SingleLine = true;
});

// If I create the client here, when I call `client.StartWorkflowAsync` the call blocks and doesn't work.
var client = await TemporalClient.ConnectAsync(new()
{
    TargetHost = "localhost:7233",
    Namespace = "default",
});

var app = builder.Build();

app.MapGet("/", async () =>
{
    app.Logger.LogInformation("We are here");
    
    // NOTE: If I connect here it works
    // var client = await TemporalClient.ConnectAsync(new()
    // {
    //     TargetHost = "localhost:7233",
    //     Namespace = "default",
    // });

    var id = $"simple-workflow-{Guid.NewGuid().ToString()}";

    // This call blocks and doesn't work
    var handle = await client.StartWorkflowAsync(
        workflow: SimpleWorkflow.Ref.RunAsync,
        arg: "Jake",
        options: new WorkflowOptions(
            id: id,
            taskQueue: "my-task-queue"
        )
    );

    var result = await handle.GetResultAsync();
    return result;
});

app.Logger.LogInformation("Started");

app.Run();

Environment/Versions

• x86 Windows
• using temporal cli

[cretz]

Good news. I can no longer replicate after updating core to get https://github.com/temporalio/sdk-core/pull/584 and setting my min tonic version to 0.9 and cargo updateing the bridge project. I will try to dig through Tonic release notes to see what it could be (though it could be one of their transitive dependencies).

I will update when I make a PR to fix this (I will likely wait for https://github.com/temporalio/sdk-core/pull/544 to be merged too).

[cretz]

I think it might be, yes. I’ll try to see if I can replicate via https://learn.microsoft.com/en-us/dotnet/api/microsoft.aspnetcore.mvc.testing.webapplicationfactory-1 in my unit tests without too much trouble.