zenstack/docs/server-side-rendering.md

Server-side rendering

You can use the service object to conduct CRUD operations on the server side directly without the overhead of HTTP requests. The service object contains members for each of the data model defined.

The server-side CRUD methods are similar signature with client-side hooks, except that they take an extra queryContext parameter for passing in the current login user. Like client-side hooks, the CRUD operations are fully protected by access policies defined in ZModel.

These methods are handy for implementing SSR (or custom API endpoints). Here's an example (using Next-Auth for authentication):

import service from '@zenstackhq/runtime/server';
import { unstable_getServerSession } from 'next-auth';
...

export const getServerSideProps = async ({
    req,
    res,
    params,
}) => {
    const session = await unstable_getServerSession(req, res, authOptions);
    const queryContext = { user: session?.user };
    const posts = await service.post.find(queryContext);
    return {
        props: { posts },
    };
};