[Feature Request] Expose UpdateID in an update handler

[Quinn-With-Two-Ns]

Is your feature request related to a problem? Please describe.

Add a way for users to obtain an update requests UpdateID in a handler.

Describe the solution you'd like

In Go I would implement it through Info call like GetUpdateInfo

func Counter(ctx workflow.Context) (int, error) {
	log := workflow.GetLogger(ctx)
	counter := 0

	if err := workflow.SetUpdateHandlerWithOptions(
		ctx,
		FetchAndAdd,
		func(ctx workflow.Context, i int) (int, error) {
                        updateID := workflow.GetUpdateInfo(ctx).UpdateID
			tmp := counter
			counter += i
			log.Info("counter updated", "addend", i, "new-value", counter, "update ID", updateID)
			return tmp, nil
		},
		workflow.UpdateHandlerOptions{Validator: nonNegative},
	); err != nil {
		return 0, err
	}

Additional context

We should also consider adding UpdateID to the interceptors as well

• Go
• Java
• TypeScript - [Feature Request] Expose updateId to Update handlers sdk-typescript#1317
• Python
• .NET
• Php
• Ruby

[stephanos]

Out of curiosity, what's the use case behind this request?

[Quinn-With-Two-Ns]

@stephanos There are multiple use cases for knowing an update ID including for continue as new (see typescript issue temporalio/sdk-typescript#1317), wanting to interact with specific update requests in a workflow (see cancellation POC temporalio/samples-go#297), or the update ID may also have some significance for the business process.