Skip to content

Error Handling

Error Handling#

Otok has one response model for loaders, actions, middleware, and server handlers.

import { fail, json, notFound, redirect, validationError } from "@kamod-ch/otok/server";

export const loader = ({ params }) => {
  if (!params.id) notFound();
  if (params.id === "latest") redirect("/users/alice");
  if (params.id === "api") return json({ user: "alice" });
  fail(400, { message: "Validation failed" });
};

export async function action({ formData }) {
  const email = String(formData?.get("email") ?? "").trim();
  if (!email.includes("@")) {
    validationError({
      fieldErrors: { email: "Enter a valid email address" },
      values: { email },
    });
  }
}

validationError() defaults to HTTP 400 and normalizes string | string[] field errors. Use status 422 when the request is understood but invalid.

Expected errors can render _error.tsx with the intended status. Unexpected exceptions hide internal details by default. Set exposeErrorDetails: true only for trusted development environments.