tools-only Workflow APIs
Step APIs
// step.do()
const result = await step.do('step name', async () => { /* logic */ });
const result = await step.do('step name', { retries, timeout }, async () => {});
// step.sleep()
await step.sleep('description', '1 hour');
await step.sleep('description', 5000); // ms
// step.sleepUntil()
await step.sleepUntil('description', Date.parse('2024-12-31'));
// step.waitForEvent()
const data = await step.waitForEvent<PayloadType>('wait', {event: 'webhook-type', timeout: '24h'}); // Default 24h, max 365d
try { const event = await step.waitForEvent('wait', { event: 'approval', timeout: '1h' }); } catch (e) { /* Timeout */ }
Instance Management
// Create single
const instance = await env.MY_WORKFLOW.create({id: crypto.randomUUID(), params: { userId: 'user123' }}); // id optional, auto-generated if omitted
// Create with custom retention (default: 3 days free, 30 days paid)
const instance = await env.MY_WORKFLOW.create({
id: crypto.randomUUID(),
params: { userId: 'user123' },
retention: '30 days' // Override default retention period
});
// Batch (max 100, idempotent: skips existing IDs)
const instances = await env.MY_WORKFLOW.createBatch([{id: 'user1', params: {name: 'John'}}, {id: 'user2', params: {name: 'Jane'}}]);
// Get & Status
const instance = await env.MY_WORKFLOW.get('instance-id');
const status = await instance.status(); // {status: 'queued' | 'running' | 'paused' | 'errored' | 'terminated' | 'complete' | 'waiting' | 'waitingForPause' | 'unknown', error?, output?}
// Control
await instance.pause(); await instance.resume(); await instance.terminate(); await instance.restart();
// Send Events
await instance.sendEvent({type: 'approval', payload: { approved: true }}); // Must match waitForEvent type
Triggering Workflows
// From Worker
export default { async fetch(req, env) { const instance = await env.MY_WORKFLOW.create({id: crypto.randomUUID(), params: { userId: 'user123' }}); return Response.json({ id: instance.id }); }};
// From Queue
export default { async queue(batch, env) { for (const msg of batch.messages) { await env.MY_WORKFLOW.create({id: `job-${msg.id}`, params: msg.body}); } }};
// From Cron
export default { async scheduled(event, env) { await env.CLEANUP_WORKFLOW.create({id: `cleanup-${Date.now()}`, params: { timestamp: event.scheduledTime }}); }};
// From Another Workflow (non-blocking)
export class ParentWorkflow extends WorkflowEntrypoint<Env, Params> {
async run(event, step) {
const child = await step.do('start child', async () => await this.env.CHILD_WORKFLOW.create({id: `child-${event.instanceId}`, params: {}}));
}
}
Error Handling
import { NonRetryableError } from 'cloudflare:workers';
// NonRetryableError
await step.do('validate', async () => {
if (!event.params.paymentMethod) throw new NonRetryableError('Payment method required');
const res = await fetch('https://api.example.com/charge', { method: 'POST' });
if (res.status === 401) throw new NonRetryableError('Invalid credentials'); // Don't retry
if (!res.ok) throw new Error('Retryable failure'); // Will retry
return res.json();
});
// Catching Errors
try { await step.do('risky op', async () => { throw new NonRetryableError('Failed'); }); } catch (e) { await step.do('cleanup', async () => {}); }
// Idempotency
await step.do('charge', async () => {
const sub = await fetch(`https://api/subscriptions/${id}`).then(r => r.json());
if (sub.charged) return sub; // Already done
return await fetch(`https://api/subscriptions/${id}`, {method: 'POST', body: JSON.stringify({ amount: 10.0 })}).then(r => r.json());
});
Type Constraints
Params and step returns must be Rpc.Serializable<T>:
// ✅ Valid types
type ValidParams = {
userId: string;
count: number;
tags: string[];
metadata: Record<string, unknown>;
};
// ❌ Invalid types
type InvalidParams = {
callback: () => void; // Functions not serializable
symbol: symbol; // Symbols not serializable
circular: any; // Circular references not allowed
};
// Step returns follow same rules
const result = await step.do('fetch', async () => {
return { userId: '123', data: [1, 2, 3] }; // ✅ Plain object
});
Sleep & Scheduling
// Relative
await step.sleep('wait 1 hour', '1 hour');
await step.sleep('wait 30 days', '30 days');
await step.sleep('wait 5s', 5000); // ms
// Absolute
await step.sleepUntil('launch date', Date.parse('24 Oct 2024 13:00:00 UTC'));
await step.sleepUntil('deadline', new Date('2024-12-31T23:59:59Z'));
Units: second, minute, hour, day, week, month, year. Max: 365 days. Sleeping instances don't count toward concurrency.
Parameters
Pass from Worker:
const instance = await env.MY_WORKFLOW.create({
id: crypto.randomUUID(),
params: { userId: 'user123', email: 'user@example.com' }
});
Access in Workflow:
async run(event: WorkflowEvent<Params>, step: WorkflowStep) {
const userId = event.params.userId;
const instanceId = event.instanceId;
const createdAt = event.timestamp;
}
CLI Trigger:
npx wrangler workflows trigger my-workflow '{"userId":"user123"}'
Wrangler CLI
npm create cloudflare@latest my-workflow -- --template "cloudflare/workflows-starter"
npx wrangler deploy
npx wrangler workflows list
npx wrangler workflows trigger my-workflow '{"userId":"user123"}'
npx wrangler workflows instances list my-workflow
npx wrangler workflows instances describe my-workflow instance-id
npx wrangler workflows instances pause/resume/terminate my-workflow instance-id
REST API
# Create
curl -X POST "https://api.cloudflare.com/client/v4/accounts/{account_id}/workflows/{workflow_name}/instances" -H "Authorization: Bearer {token}" -d '{"id":"custom-id","params":{"userId":"user123"}}'
# Status
curl "https://api.cloudflare.com/client/v4/accounts/{account_id}/workflows/{workflow_name}/instances/{instance_id}/status" -H "Authorization: Bearer {token}"
# Send Event
curl -X POST "https://api.cloudflare.com/client/v4/accounts/{account_id}/workflows/{workflow_name}/instances/{instance_id}/events" -H "Authorization: Bearer {token}" -d '{"type":"approval","payload":{"approved":true}}'
See: configuration.md, patterns.md