Roles & Permissions | ideal-auth

ideal-auth intentionally does not include a roles and permissions system. Access control schemas vary significantly between applications — flat roles, hierarchical RBAC, fine-grained permissions, attribute-based access control — and baking one into the library would either be too simple for real use cases or too opinionated.

Instead, ideal-auth gives you the building blocks: resolveUser fetches your user from the database (with whatever role/permission data you need), and you write the access control checks that match your schema.

This guide covers recommended patterns you can adopt.

Why it’s not built in

Different applications need fundamentally different models:

A blog might need admin / editor / viewer roles
A SaaS platform might need per-resource permissions like invoices.create, invoices.delete
A multi-tenant system might need organization-scoped roles (org:admin, org:member)
An enterprise system might need attribute-based policies (“users in department X can access resource Y during business hours”)

Any built-in system would either cover only the simplest case or impose a schema you would eventually fight against. By keeping roles and permissions in your application layer, you get full control over your data model and access checks.

Simple roles pattern

The simplest approach: each user has a single role field.

Database schema

CREATE TABLE users (
  id       TEXT PRIMARY KEY,
  email    TEXT UNIQUE NOT NULL,
  password TEXT NOT NULL,
  role     TEXT NOT NULL DEFAULT 'viewer'  -- 'admin', 'editor', 'viewer'
);

Helper functions

type Role = 'admin' | 'editor' | 'viewer';

function hasRole(user: { role: string }, role: Role): boolean {
  return user.role === role;
}

function hasMinRole(user: { role: string }, minRole: Role): boolean {
  const hierarchy: Role[] = ['viewer', 'editor', 'admin'];
  return hierarchy.indexOf(user.role as Role) >= hierarchy.indexOf(minRole);
}

Usage in a route handler

import { createAuth } from 'ideal-auth';

const auth = createAuth({
  secret: process.env.IDEAL_AUTH_SECRET!,
  cookie: cookieBridge,
  resolveUser: (id) => db.user.findUnique({ where: { id } }),
  // ...
});

// POST /api/admin/users
export async function manageUsers(req, res) {
  const session = auth();
  const user = await session.user();

  if (!user) {
    return res.status(401).json({ error: 'Not authenticated' });
  }

  if (!hasRole(user, 'admin')) {
    return res.status(403).json({ error: 'Forbidden' });
  }

  // ... admin-only logic
}

Permission-based pattern

For finer-grained control, assign permissions directly to users.

Database schema

CREATE TABLE users (
  id          TEXT PRIMARY KEY,
  email       TEXT UNIQUE NOT NULL,
  password    TEXT NOT NULL,
  permissions TEXT[] NOT NULL DEFAULT '{}'
  -- e.g., ['posts.create', 'posts.delete', 'users.manage']
);

Helper functions

function hasPermission(
  user: { permissions: string[] },
  permission: string,
): boolean {
  return user.permissions.includes(permission);
}

function hasAnyPermission(
  user: { permissions: string[] },
  permissions: string[],
): boolean {
  return permissions.some((p) => user.permissions.includes(p));
}

function hasAllPermissions(
  user: { permissions: string[] },
  permissions: string[],
): boolean {
  return permissions.every((p) => user.permissions.includes(p));
}

Usage

// POST /api/posts
export async function createPost(req, res) {
  const session = auth();
  const user = await session.user();

  if (!user) {
    return res.status(401).json({ error: 'Not authenticated' });
  }

  if (!hasPermission(user, 'posts.create')) {
    return res.status(403).json({ error: 'Forbidden' });
  }

  // ... create post
}

Role + permission hybrid

The most flexible approach: roles define groups of permissions, but access checks use permissions. This lets you add or remove capabilities from roles without changing your authorization code.

Permission mapping

const ROLE_PERMISSIONS: Record<string, string[]> = {
  admin: [
    'posts.create',
    'posts.edit',
    'posts.delete',
    'posts.publish',
    'users.list',
    'users.manage',
    'settings.manage',
  ],
  editor: [
    'posts.create',
    'posts.edit',
    'posts.delete',
    'posts.publish',
  ],
  viewer: [
    'posts.create',
  ],
};

function getPermissionsForRole(role: string): string[] {
  return ROLE_PERMISSIONS[role] ?? [];
}

function userHasPermission(
  user: { role: string },
  permission: string,
): boolean {
  return getPermissionsForRole(user.role).includes(permission);
}

Middleware factory

Create a reusable middleware function that checks permissions:

function requirePermission(permission: string) {
  return async (req, res, next) => {
    const session = auth();
    const user = await session.user();

    if (!user) {
      return res.status(401).json({ error: 'Not authenticated' });
    }

    if (!userHasPermission(user, permission)) {
      return res.status(403).json({ error: 'Forbidden' });
    }

    req.user = user;
    next();
  };
}

// Usage
app.post('/api/posts', requirePermission('posts.create'), createPost);
app.delete('/api/posts/:id', requirePermission('posts.delete'), deletePost);
app.get('/api/admin/users', requirePermission('users.manage'), listUsers);

Database schema patterns

Simple: role column on users table

Best for applications with a small, fixed set of roles.

CREATE TABLE users (
  id       TEXT PRIMARY KEY,
  email    TEXT UNIQUE NOT NULL,
  password TEXT NOT NULL,
  role     TEXT NOT NULL DEFAULT 'viewer'
);

Medium: roles table with join table

Best when roles are dynamic and managed through an admin interface.

CREATE TABLE roles (
  id   TEXT PRIMARY KEY,
  name TEXT UNIQUE NOT NULL  -- 'admin', 'editor', 'viewer'
);

CREATE TABLE user_roles (
  user_id TEXT REFERENCES users(id) ON DELETE CASCADE,
  role_id TEXT REFERENCES roles(id) ON DELETE CASCADE,
  PRIMARY KEY (user_id, role_id)
);

// resolveUser fetches roles
async function resolveUser(id: string) {
  const user = await db.user.findUnique({
    where: { id },
    include: {
      userRoles: {
        include: { role: true },
      },
    },
  });

  if (!user) return null;

  return {
    ...user,
    roles: user.userRoles.map((ur) => ur.role.name),
  };
}

Advanced: roles + permissions + role_permissions

Best for complex applications where permissions can be assigned independently of roles.

CREATE TABLE roles (
  id   TEXT PRIMARY KEY,
  name TEXT UNIQUE NOT NULL
);

CREATE TABLE permissions (
  id   TEXT PRIMARY KEY,
  name TEXT UNIQUE NOT NULL  -- 'posts.create', 'users.manage'
);

CREATE TABLE role_permissions (
  role_id       TEXT REFERENCES roles(id) ON DELETE CASCADE,
  permission_id TEXT REFERENCES permissions(id) ON DELETE CASCADE,
  PRIMARY KEY (role_id, permission_id)
);

CREATE TABLE user_roles (
  user_id TEXT REFERENCES users(id) ON DELETE CASCADE,
  role_id TEXT REFERENCES roles(id) ON DELETE CASCADE,
  PRIMARY KEY (user_id, role_id)
);

-- Optional: direct user-level permission overrides
CREATE TABLE user_permissions (
  user_id       TEXT REFERENCES users(id) ON DELETE CASCADE,
  permission_id TEXT REFERENCES permissions(id) ON DELETE CASCADE,
  PRIMARY KEY (user_id, permission_id)
);

async function resolveUser(id: string) {
  const user = await db.user.findUnique({ where: { id } });
  if (!user) return null;

  // Collect permissions from roles
  const rolePermissions = await db.$queryRaw`
    SELECT DISTINCT p.name
    FROM user_roles ur
    JOIN role_permissions rp ON rp.role_id = ur.role_id
    JOIN permissions p ON p.id = rp.permission_id
    WHERE ur.user_id = ${id}
  `;

  // Collect direct user permissions
  const directPermissions = await db.$queryRaw`
    SELECT p.name
    FROM user_permissions up
    JOIN permissions p ON p.id = up.permission_id
    WHERE up.user_id = ${id}
  `;

  const allPermissions = new Set([
    ...rolePermissions.map((r) => r.name),
    ...directPermissions.map((r) => r.name),
  ]);

  return {
    ...user,
    permissions: [...allPermissions],
  };
}

Framework integration examples

Next.js middleware

// middleware.ts
import { NextResponse } from 'next/server';
import type { NextRequest } from 'next/server';

// Define which routes require which roles
const PROTECTED_ROUTES: Record<string, string[]> = {
  '/admin': ['admin'],
  '/editor': ['admin', 'editor'],
};

export async function middleware(request: NextRequest) {
  const { pathname } = request.nextUrl;

  // Check if this route requires a role
  for (const [route, allowedRoles] of Object.entries(PROTECTED_ROUTES)) {
    if (pathname.startsWith(route)) {
      // Role checking must happen in a server component or API route
      // because middleware cannot access the database directly.
      // Use a lightweight check here (e.g., a role claim in the cookie)
      // and do the authoritative check in the server component.
      const hasSession = request.cookies.has('ideal_session');
      if (!hasSession) {
        return NextResponse.redirect(new URL('/login', request.url));
      }
    }
  }

  return NextResponse.next();
}

// app/admin/page.tsx (Server Component — authoritative check)
import { auth } from '@/lib/auth';
import { redirect } from 'next/navigation';

export default async function AdminPage() {
  const session = auth();
  const user = await session.user();

  if (!user || user.role !== 'admin') {
    redirect('/');
  }

  return <div>Admin panel</div>;
}

SvelteKit hooks

// src/hooks.server.ts
import { redirect } from '@sveltejs/kit';
import type { Handle } from '@sveltejs/kit';
import { auth } from '$lib/auth';

export const handle: Handle = async ({ event, resolve }) => {
  const session = auth();
  const user = await session.user();

  event.locals.user = user;

  // Protect admin routes
  if (event.url.pathname.startsWith('/admin')) {
    if (!user || user.role !== 'admin') {
      throw redirect(302, '/');
    }
  }

  return resolve(event);
};

Server action guard pattern

// lib/guards.ts
import { auth } from './auth';

export async function requireRole(role: string) {
  const session = auth();
  const user = await session.user();

  if (!user) {
    throw new Error('Not authenticated');
  }

  if (user.role !== role) {
    throw new Error('Forbidden');
  }

  return user;
}

export async function requirePermission(permission: string) {
  const session = auth();
  const user = await session.user();

  if (!user) {
    throw new Error('Not authenticated');
  }

  if (!userHasPermission(user, permission)) {
    throw new Error('Forbidden');
  }

  return user;
}

// app/actions.ts
'use server';
import { requirePermission } from '@/lib/guards';

export async function deletePost(postId: string) {
  const user = await requirePermission('posts.delete');

  await db.post.delete({ where: { id: postId } });
}

Security notes

Do not store roles or permissions in the session cookie. Session cookies contain only { uid, iat, exp }. If you store a role in the cookie and the user’s role changes, the cookie will be stale until it expires. Always fetch the current role from the database via resolveUser.
Fetch fresh permissions on every request. The resolveUser function is called each time you call session.user(). This means permission changes take effect immediately — no need to force a logout or wait for the session to expire.
Prefer permission checks over role checks. Checking hasPermission(user, 'posts.delete') is more maintainable than user.role === 'admin' || user.role === 'editor'. When you add a new role, you only need to update the role-to-permissions mapping, not every authorization check.
Fail closed. If a user’s role cannot be determined (e.g., the database query fails), deny access. Never default to allowing access on error.