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Validation Example

Validate query and body with per-method schemas in schema.ts, then read the validated data from ctx.validated.

// src/api/products/schema.ts
import { z } from "zod";

export const GET = { query: z.object({ limit: z.coerce.number().optional() }) };
export const POST = { body: z.object({ name: z.string().min(1), price: z.number() }) };
// src/api/products/route.ts
import { defineRoute } from "burger-api";
import { GET as GETSchema, POST as POSTSchema } from "./schema";

export const GET = defineRoute(GETSchema, (ctx) => {
  const { limit } = ctx.validated.query;
  return Response.json({ items: [], limit });
});

export const POST = defineRoute(POSTSchema, (ctx) => {
  const { name, price } = ctx.validated.body;
  return Response.json({ name, price });
});

defineRoute(schema, handler) types ctx.validated from the matching schema export, so limit is a validated number, not a string, and there is no BurgerContext<typeof GET> generic to write by hand (though it still works if you prefer it).

With z.coerce.number(), a request like ?limit=10 gives you the number 10 (not the string "10"). You can also turn coercion on app-wide: see Coercion.

Because POST declares a body schema, the request must be JSON (application/json or application/*+json). Other content types get 415 Unsupported Media Type before the handler runs, and ctx.validated.body is non-optional in the type.

See Schema Definition for the full schema shape, Validation Errors for how failures are reported (default 422 with RFC 9457 problem details), and the CRUD API example for a complete route directory.