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Validation Configuration

Validation behavior is controlled by the validation option in the Burger constructor.

validation​

src/index.ts
import { Burger } from "burger-api";

const app = new Burger({
  apiDir: "./src/api",
  validation: {
    // Turn on automatic type conversion app-wide (default: false)
    coerce: true,

    // How to handle response validation: "off" | "dev" | "enforce" (default: "dev")
    responseValidation: "dev",

    // Error body shape: "plain" | "problem+json" (default: "problem+json")
    errorFormat: "problem+json",

    // Fully custom error body (optional)
    errorRenderer: (result, { slot, status }) => {
      return Response.json(
        { ok: false, issues: result.issues },
        { status }
      );
    },
  },
});
OptionValuesDefaultWhat it does
coercebooleanfalseEnable automatic type conversion for query/params/headers/cookies.
responseValidation"off" | "dev" | "enforce""dev"Observe-only in dev; enforce returns a safe error on mismatch.
errorFormat"plain" | "problem+json""problem+json"The shape of the error body.
statusnumber422Status code used for request validation failures.
errorRenderer(result, { slot, status }) => ResponseNoneOverride the error body completely.

Reusing schemas across routes​

To share a shape between routes, define it once in its own file and import it:

src/schemas.ts
import { z } from "zod";

export const Pagination = z.object({
  page: z.coerce.number().int().min(1).default(1),
  limit: z.coerce.number().int().min(1).max(100).default(20),
});
api/items/schema.ts
import { Pagination } from "../../schemas";

export const GET = { query: Pagination };