Add Workflow Types to workers-types

[AbhiPrasad]

ref getsentry/sentry-javascript#16704

The following types:

WorkflowEntrypoint,
WorkflowEvent,
WorkflowSleepDuration,
WorkflowStep,
WorkflowStepConfig,
WorkflowStepEvent,
WorkflowTimeoutDuration,

are not available via @cloudflare/workers-types (tested with 4.20250620.0). The Sentry Cloudflare SDK needs them for our upcoming Cloudflare Workflows instrumentation. It would be great if they got exposed!

The Sentry SDK ended up vendoring them in, but this will cause problems as the types get updated.

[emily-shen]

Hi, perhaps i'm misunderstanding you, but it looks like these types are available?
https://github.com/cloudflare/workerd/blob/main/types/generated-snapshot/latest/index.d.ts#L7999
https://github.com/cloudflare/workerd/blob/main/types/generated-snapshot/latest/index.d.ts#L7969
etc.

(these snapshots match what is published as workers-types)

[AbhiPrasad]

I apologize if I'm misunderstanding something, but when I tried to import this from the package I couldn't access WorkflowStep: https://stackblitz.com/edit/vitejs-vite-lobp6cn4?file=src%2Fmain.ts

[petebacondarwin]

So WorkflowStep is actually a native abstract class exported from workerd.
It's available by importing from "cloudflare:workers".
To ensure that "virtual module" is available in your code you need to add @cloudflare/workers-types to the tsconfig.

So to in your code you can use:

import type { WorkflowStep } from "cloudflare:workers";

let x: WorkflowStep;

and in your tsconfig.json you need:

{
	"compilerOptions": {
		// ...
		"types": [
			"@cloudflare/workers-types"
		]
	}
}

[AbhiPrasad]

I'm building a library that vendors in these types: https://github.com/getsentry/sentry-javascript/tree/develop/packages/cloudflare

importing from cloudflare:workers is breaking some user setups (getsentry/sentry-javascript#16099) so I'm trying to move off of that to explicitly always import from @cloudflare/workers-types.

I would much prefer if we can avoid the virtual module for cloudflare library development.