nuxt4-demo/server/service/auth/context.ts

import type { H3Event } from "h3";
import { SESSION_COOKIE_NAME, UNAUTHORIZED_MESSAGE } from "#server/constants/auth";
import { getCurrentUser } from ".";

type MinimalUser = {
  id: number;
  username: string;
};

export function createAuthContext(event: H3Event) {
  let currentUserPromise: Promise<MinimalUser | null> | undefined;

  const getCurrent = async () => {
    if (!currentUserPromise) {
      currentUserPromise = (async () => {
        const sessionId = getCookie(event, SESSION_COOKIE_NAME);
        if (!sessionId) {
          return null;
        }
        return getCurrentUser(sessionId);
      })();
    }
    return currentUserPromise;
  };

  const requireUser = async () => {
    const user = await getCurrent();
    if (!user) {
      throw createError({
        statusCode: 401,
        statusMessage: UNAUTHORIZED_MESSAGE,
        data: { code: "UNAUTHORIZED" },
      });
    }
    return user;
  };

  return {
    getCurrent,
    requireUser,
  };
}