Workflow

This guide explains how to create, bind and use Cloudflare Workflows within your Worker scripts.

1. Create a Workflow

   At a bare minimum, you need to create a Workflow object as a stable reference to your Workflow.

   import { Workflow } from "alchemy/cloudflare";
   
   const orderProcessor = Workflow("orderProcessor", {
     className: "OrderProcessor",
     // defaults to the resource ID ("orderProcessor") if not specified
     // workflowName: "order-processing-workflow",
   });

2. Bind the Workflow to a Worker

   Create a Worker and bind your workflow to it so it can be accessed from your Worker script.

   export const worker = await Worker("Worker", {
     name: "my-worker",
     entrypoint: "./index.ts"
     bindings: {
       // bind the workflow to your Worker
       ORDER_PROCESSOR: orderProcessor,
     },
   });

3. Implement the Workflow class

   Now, we have a Worker with a Workflow running within it. To use this Workflow, our Worker script must include a class for the workflow.

   A simple workflow may look like so:

   export class OrderProcessor extends WorkflowEntrypoint {
     constructor(state, env) {
       this.state = state;
       this.env = env;
     }
   
     async run(event, step) {
       const shippingDetails = await step.do("process-shipping", async () => {
         return {
           success: true,
           shipmentId: event.payload.shipmentId,
           message: "Shipment scheduled successfully",
         };
       });
       return shippingDetails;
     }
   }

   Tip

   See Cloudflare’s Workflow Guide for more details on implementing workflows.

4. Trigger the Workflow from your Worker

   Now, our fetch handler can create a Workflow instance (start a workflow) via the ORDER_PROCESSOR binding:

   import type { worker } from "./alchemy.run";
   
   export default {
     async fetch(request: Request, env: typeof worker.Env) {
       const url = new URL(request.url);
       const params = { orderId: "test-123", amount: 99.99 };
       const instance = await env.ORDER_PROCESSOR.create(params);
   
       return Response.json({
         id: instance.id,
         details: await instance.status(),
         success: true,
         orderId: params.orderId,
         message: "Order processed successfully",
       });
     },
   };

5. (Optional) Rename the Class

   Alchemy takes care of migrations automatically when you rename the class name.

   import { Workflow } from "alchemy/cloudflare";
   
   const orderProcessor = Workflow("orderProcessor", {
     className: "OrderProcessor",
     className: "OrderProcessorV2",
   });

   Caution

   You cannot rename the "orderProcessor" ID in Workflow("orderProcessor") - we call this the “stable identifier” for the Workflow and it is immutable for the lifetime of the application.

6. (Optional) Set up Cross-Script Workflow Binding

   You can share workflows across multiple Workers, allowing one Worker to trigger workflows defined in another Worker. This is useful for creating modular architectures where different Workers handle different concerns.