What is @temporalio/workflow?
@temporalio/workflow is a package for building and managing workflows using Temporal, a microservices orchestration platform. It allows developers to write workflows in a straightforward and maintainable way, handling complex state management, retries, and timeouts.
What are @temporalio/workflow's main functionalities?
Defining a Workflow
This feature allows you to define a workflow using the `defineWorkflow` function. The workflow logic is written as an async function, making it easy to manage asynchronous operations.
const { defineWorkflow } = require('@temporalio/workflow');
const myWorkflow = defineWorkflow(async function() {
// Workflow logic here
console.log('Workflow started');
await someActivity();
console.log('Workflow completed');
});
Executing Activities
Activities are the building blocks of workflows. This feature allows you to define activities that can be executed within a workflow. Activities can perform tasks such as calling external services or processing data.
const { defineActivity } = require('@temporalio/workflow');
const someActivity = defineActivity(async function() {
// Activity logic here
return 'Activity result';
});
Handling Workflow State
Temporal workflows can maintain state across different steps. This feature allows you to set and get state within a workflow, making it easier to manage complex workflows with multiple steps.
const { defineWorkflow, setState, getState } = require('@temporalio/workflow');
const myWorkflow = defineWorkflow(async function() {
setState('step', 1);
console.log('Step 1');
await someActivity();
setState('step', 2);
console.log('Step 2');
await anotherActivity();
console.log('Workflow completed');
});
Retrying Failed Activities
Temporal provides built-in support for retrying failed activities. This feature allows you to specify retry policies for activities, ensuring that transient failures are automatically retried.
const { defineActivity } = require('@temporalio/workflow');
const someActivity = defineActivity(async function() {
// Activity logic here
throw new Error('Activity failed');
}, { retry: { maximumAttempts: 3 } });
Other packages similar to @temporalio/workflow
bull
Bull is a Node.js library for creating robust background jobs and message queues. It provides features like job retries, concurrency control, and job scheduling. Compared to @temporalio/workflow, Bull is more focused on job queues and less on complex workflow orchestration.
agenda
Agenda is a lightweight job scheduling library for Node.js. It allows you to define and schedule jobs with support for recurring jobs and job retries. While it provides some workflow capabilities, it is not as feature-rich as @temporalio/workflow in terms of state management and orchestration.
node-resque
Node-resque is a Redis-backed job queue for Node.js. It supports job retries, scheduling, and concurrency control. Similar to Bull and Agenda, it is more focused on job queues rather than comprehensive workflow orchestration like @temporalio/workflow.