vtex-io-service-apps

Structure a VTEX IO backend service by using the @vtex/api Service entry point to wire routes, resolvers, and IOClients. This ensures proper client registration and consistent middleware usage across your node-based app.

Use IOClients and JanusClient in a VTEX IO app by extending @vtex/api client classes and accessing them via ctx.clients. This standardizes HTTP calls, authentication context, caching, and metrics for backend requests.

Create REST API routes and GraphQL resolvers in VTEX IO node apps by composing them within the Service entry point. This keeps route counts manageable and ensures correct wiring with registered clients and event handlers.

Yes, you can use ExternalClient to handle HTTP calls to external APIs outside VTEX IO. It integrates with the @vtex/api client structure, ensuring consistent caching and metrics while accessing third-party services via ctx.clients.

Implement event handlers and scheduled tasks in VTEX IO backend services when you need to process asynchronous platform events or execute automated routines. They are wired directly into the Service entry point alongside REST routes and GraphQL resolvers.

Standardizing client usage with @vtex/api reduces boilerplate and errors by providing built-in authentication, caching, and metrics. Custom HTTP implementations lack this native VTEX IO context integration, leading to inconsistent backend service behavior.