validate — schema validation

Imported from the facade: import { validate, z } from "@/framework/facade.js".

Runs any Zod schema against untrusted input (request bodies outside OpenAPI routes, config values, webhook payloads) and throws a consistent 422 failure on mismatch. See OpenAPI.

Functions

Function	Signature	Description
validate	(schema: z.ZodTypeAny, data: unknown) => Promise<z.infer<T>>	Runs safeParseAsync; returns typed data or throws a 422 error

Use cases

Validate a plain request body

import { validate } from "@/framework/facade.js";

export const store = async (c) => {
  const body = await validate(CreatePostSchema, await c.req.json());
  // body is inferred from CreatePostSchema — no casts needed
};

Structured failure shape

When validation fails, validate throws an object that the error handler renders as 422:

try {
  await validate(CreatePostSchema, rawBody);
} catch (error) {
  // error.status === 422
  // error.message === "Validation failed"
  // error.errors === result.error.flatten()  // { formErrors, fieldErrors }
}

Validate non-HTTP input

import { validate, z } from "@/framework/facade.js";

const ConfigSchema = z.object({
  host: z.string(),
  port: z.coerce.number().int(),
});

// Throws 422-shaped error when env/input is invalid
const config = await validate(ConfigSchema, { host, port });

Real world — route schemas in the type module

Query/params schemas use z.coerce so "?page=3" arrives as a real number, and tiny response schemas stay inline in routes:

// modules/type/controllers/type.schema.ts
export const TypeItemSchema = z.object({ id: z.number(), name: z.string() });
export const TypeIdParamsSchema = z.object({ id: z.coerce.number().int().positive() });
export const TypeQuerySchema = z.object({
  search: z.string().optional(),
  page: z.coerce.number().optional(),
  size: z.coerce.number().optional(),
  per_page: z.coerce.number().optional(),
});

// modules/auth/routes/api.ts — composed response schema
responses: {
  [HttpStatusCodes.OK]: jsonContent(
    z.object({ message: z.string(), data: z.array(UserSchema) }),
    "User list"
  ),
}

Notes

• Prefer OpenAPI route schemas in endpoints — Hono validates automatically via c.req.valid("json"). Use validate when schema validation is needed outside the route layer.
• The thrown value is a plain object (not an Error instance) so the framework's error middleware can map it directly to an HTTP 422 response.