LMS (learning platform) on Nuxt 4, Postgres (Neon) and Clerk

import { drizzle } from "drizzle-orm/postgres-js";
import postgres from "postgres";

// Neon pooled endpoint = PgBouncer transaction mode → prepared statements off.
// ponytail: single module-level client; the serverless runtime + PgBouncer do
// the pooling, so no custom pool/globalThis singleton dance needed.
const client = postgres(process.env.DATABASE_URL!, { prepare: false });

export const db = drizzle({ client });

// Clerk on Nuxt 4 is a Nuxt MODULE: registering "@clerk/nuxt" auto-injects
// <ClerkProvider>, the Vue components (<SignIn/>, <UserButton/>), and a server plugin that
// attaches the Clerk Auth object to event.context.auth — no manual provider wiring.
// ponytail: Clerk is hosted — set NUXT_PUBLIC_CLERK_PUBLISHABLE_KEY (read client-side by the
// module) and NUXT_CLERK_SECRET_KEY (read server-side by clerkMiddleware) in the env; the
// module picks them up automatically, so nothing here references them.
// ponytail: Nuxt provides defineNuxtConfig as a global at runtime; import it explicitly from
// "nuxt/config" so this config type-checks under standalone tsc.
import { defineNuxtConfig } from "nuxt/config";

export default defineNuxtConfig({
  modules: ["@clerk/nuxt"],
});

// Clerk route protection as a Nitro server middleware — the Nuxt 4 analog of
// Next's clerkMiddleware proxy + auth.protect(). clerkMiddleware() wraps a handler that runs
// on every request with the Clerk Auth object on event.context.auth; here we guard the SaaS
// app surface and redirect signed-out users to the hosted sign-in.
// ponytail: Nuxt AUTO-IMPORTS the h3 helpers at runtime; we import getRequestURL + sendRedirect
// EXPLICITLY from h3 (Nitro's engine, a nuxt dep) so this type-checks under standalone tsc.
import { clerkMiddleware } from "@clerk/nuxt/server";
import { getRequestURL, sendRedirect, type H3Event } from "h3";

// ponytail: guard the SaaS app surface; widen the prefixes per app-type.
const PROTECTED_PREFIXES = ["/dashboard", "/settings"];

export default clerkMiddleware((event) => {
  // clerkMiddleware injects Clerk's Auth object on event.context.auth (see @clerk/nuxt module).
  const { isAuthenticated } = event.context.auth();
  // ponytail: @clerk/nuxt bundles its OWN h3 copy, so clerkMiddleware types `event` against that
  // copy; re-narrow to the top-level h3 H3Event (the SAME runtime object) so the explicitly
  // imported getRequestURL/sendRedirect type-check standalone — only the compiled d.ts differ.
  const h3Event = event as unknown as H3Event;
  const { pathname } = getRequestURL(h3Event);
  if (!isAuthenticated && PROTECTED_PREFIXES.some((prefix) => pathname.startsWith(prefix))) {
    return sendRedirect(h3Event, "/sign-in", 302);
  }
});

// === file: server/db/schema.ts ===
import { relations, sql } from "drizzle-orm";
import {
  check,
  index,
  integer,
  pgTable,
  text,
  timestamp,
  unique,
  uuid,
} from "drizzle-orm/pg-core";
// Better Auth owns identity; we only reference its `user` table by id.
import { user } from "./auth-schema";

export type CourseStatus = "draft" | "published" | "archived";
export type LessonContentType = "video" | "text" | "quiz";
export type ProgressStatus = "not_started" | "in_progress" | "completed";

/** Catalog root. Each course has one instructor (a Better Auth user). */
export const courses = pgTable(
  "courses",
  {
    id: uuid("id").primaryKey().defaultRandom(),
    slug: text("slug").notNull().unique(),
    title: text("title").notNull(),
    // Better Auth's user.id is text — match it, don't recast.
    instructorId: text("instructor_id")
      .notNull()
      .references(() => user.id, { onDelete: "cascade" }),
    status: text("status")
      .$type<CourseStatus>()
      .notNull()
      .default("draft"),
    createdAt: timestamp("created_at", { withTimezone: true })
      .notNull()
      .defaultNow(),
  },
  (t) => [
    index("idx_course_slug").on(t.slug),
    index("idx_course_instructor").on(t.instructorId),
    check(
      "courses_status_check",
      sql`${t.status} in ('draft','published','archived')`,
    ),
  ],
);

/** Ordered sections within a course. position drives curriculum order. */
export const modules = pgTable(
  "modules",
  {
    id: uuid("id").primaryKey().defaultRandom(),
    courseId: uuid("course_id")
      .notNull()
      .references(() => courses.id, { onDelete: "cascade" }),
    title: text("title").notNull(),
    position: integer("position").notNull().default(0),
    createdAt: timestamp("created_at", { withTimezone: true })
      .notNull()
      .defaultNow(),
  },
  (t) => [index("idx_module_course").on(t.courseId, t.position)],
);

/** Leaf content unit. contentType selects how the lesson renders/plays. */
export const lessons = pgTable(
  "lessons",
  {
    id: uuid("id").primaryKey().defaultRandom(),
    moduleId: uuid("module_id")
      .notNull()
      .references(() => modules.id, { onDelete: "cascade" }),
    title: text("title").notNull(),
    position: integer("position").notNull().default(0),
    contentType: text("content_type")
      .$type<LessonContentType>()
      .notNull()
      .default("text"),
    createdAt: timestamp("created_at", { withTimezone: true })
      .notNull()
      .defaultNow(),
  },
  (t) => [
    index("idx_lesson_module").on(t.moduleId, t.position),
    check(
      "lessons_content_type_check",
      sql`${t.contentType} in ('video','text','quiz')`,
    ),
  ],
);

/** course <-> student join. The composite unique is the enrollment identity. */
export const enrollments = pgTable(
  "enrollments",
  {
    id: uuid("id").primaryKey().defaultRandom(),
    courseId: uuid("course_id")
      .notNull()
      .references(() => courses.id, { onDelete: "cascade" }),
    studentId: text("student_id")
      .notNull()
      .references(() => user.id, { onDelete: "cascade" }),
    enrolledAt: timestamp("enrolled_at", { withTimezone: true })
      .notNull()
      .defaultNow(),
  },
  (t) => [
    unique("enrollments_course_student_unique").on(t.courseId, t.studentId),
    // Drives the learner's "my courses" list.
    index("idx_enrollment_student").on(t.studentId),
  ],
);

/** Per-lesson learner state. The composite unique is one row per student+lesson. */
export const lessonProgress = pgTable(
  "lesson_progress",
  {
    id: uuid("id").primaryKey().defaultRandom(),
    lessonId: uuid("lesson_id")
      .notNull()
      .references(() => lessons.id, { onDelete: "cascade" }),
    studentId: text("student_id")
      .notNull()
      .references(() => user.id, { onDelete: "cascade" }),
    status: text("status")
      .$type<ProgressStatus>()
      .notNull()
      .default("not_started"),
    completedAt: timestamp("completed_at", { withTimezone: true }),
  },
  (t) => [
    unique("lesson_progress_student_lesson_unique").on(
      t.studentId,
      t.lessonId,
    ),
    // Drives the per-learner progress lookup (student + lesson).
    index("idx_progress_student_lesson").on(t.studentId, t.lessonId),
    check(
      "lesson_progress_status_check",
      sql`${t.status} in ('not_started','in_progress','completed')`,
    ),
  ],
);

export const coursesRelations = relations(courses, ({ one, many }) => ({
  instructor: one(user, {
    fields: [courses.instructorId],
    references: [user.id],
  }),
  modules: many(modules),
  enrollments: many(enrollments),
}));

export const modulesRelations = relations(modules, ({ one, many }) => ({
  course: one(courses, {
    fields: [modules.courseId],
    references: [courses.id],
  }),
  lessons: many(lessons),
}));

export const lessonsRelations = relations(lessons, ({ one, many }) => ({
  module: one(modules, {
    fields: [lessons.moduleId],
    references: [modules.id],
  }),
  progress: many(lessonProgress),
}));

export const enrollmentsRelations = relations(enrollments, ({ one }) => ({
  course: one(courses, {
    fields: [enrollments.courseId],
    references: [courses.id],
  }),
  student: one(user, {
    fields: [enrollments.studentId],
    references: [user.id],
  }),
}));

export const lessonProgressRelations = relations(lessonProgress, ({ one }) => ({
  lesson: one(lessons, {
    fields: [lessonProgress.lessonId],
    references: [lessons.id],
  }),
  student: one(user, {
    fields: [lessonProgress.studentId],
    references: [user.id],
  }),
}));

// === file: server/db/auth-schema.ts ===
import { pgTable, text, timestamp } from "drizzle-orm/pg-core";

// Local mirror of Clerk identity — the FK target app-type schemas reference as user.
// id = Clerk's user id, so existing user_id foreign keys resolve once the sync runs.
// This IS the auth-schema slot for Clerk cells: the SaaS schema's ./auth-schema FK
// target (src/db/auth-schema.ts) resolves here, same slot Better Auth's generated file fills.
export const user = pgTable("user", {
  id: text("id").primaryKey(), // = Clerk user id
  email: text("email"),
  firstName: text("first_name"),
  lastName: text("last_name"),
  imageUrl: text("image_url"),
  updatedAt: timestamp("updated_at", { withTimezone: true }), // staleness key (Clerk updated_at)
  createdAt: timestamp("created_at", { withTimezone: true }).notNull().defaultNow(),
});

import { and, eq, isNull, lt, or } from "drizzle-orm";
import { user } from "~~/server/db/auth-schema";

export type ClerkUserEvent = {
  type: string;
  data: {
    id: string;
    email_addresses?: { email_address: string }[];
    first_name?: string | null;
    last_name?: string | null;
    image_url?: string | null;
    updated_at?: number;
  };
};

// Idempotent + concurrency-safe sync of a Clerk user into the local user table.
// Keyed on id (= Clerk id, the PK); the staleness guard lives in the UPDATE WHERE so
// a late/older event cannot clobber newer state. user.deleted removes the row.
export async function recordClerkEvent(
  // ponytail: loosely typed Drizzle client so the emitted core stays portable.
  db: any,
  event: ClerkUserEvent,
): Promise<{ changed: boolean }> {
  const d = event.data;
  if (event.type === "user.deleted") {
    const deleted = await db.delete(user).where(eq(user.id, d.id)).returning({ id: user.id });
    return { changed: deleted.length > 0 };
  }

  const email = d.email_addresses?.[0]?.email_address ?? null;
  const eventAt = new Date(d.updated_at ?? 0);
  const fields = {
    email,
    firstName: d.first_name ?? null,
    lastName: d.last_name ?? null,
    imageUrl: d.image_url ?? null,
    updatedAt: eventAt,
  };

  const updated = await db
    .update(user)
    .set(fields)
    .where(and(eq(user.id, d.id), or(isNull(user.updatedAt), lt(user.updatedAt, eventAt))))
    .returning({ id: user.id });
  if (updated.length > 0) return { changed: true };

  const [existing] = await db.select({ id: user.id }).from(user).where(eq(user.id, d.id)).limit(1);
  if (existing) return { changed: false };

  const inserted = await db
    .insert(user)
    .values({ id: d.id, ...fields })
    .onConflictDoNothing({ target: user.id })
    .returning({ id: user.id });
  return { changed: inserted.length > 0 };
}

// Clerk identity webhook for Nuxt 4 (Nitro server route). The .post.ts
// suffix binds this handler to POST /api/webhooks/clerk. Clerk webhooks are svix: verify
// the signature, then hand the event to the idempotent recordClerkEvent.
// ponytail: Nuxt AUTO-IMPORTS the h3 helpers at runtime; we import defineEventHandler /
// readRawBody / getHeaders / createError EXPLICITLY from h3 (Nitro's engine, a nuxt dep) so
// this handler type-checks under standalone tsc — the one idiom trade for verifiability.
import { createError, defineEventHandler, getHeaders, readRawBody } from "h3";
import { Webhook } from "svix";
import { db } from "~~/server/lib/db";
import { recordClerkEvent, type ClerkUserEvent } from "~~/server/lib/identity/record";

const USER_EVENTS = new Set(["user.created", "user.updated", "user.deleted"]);

export default defineEventHandler(async (event) => {
  const secret = process.env.CLERK_WEBHOOK_SECRET;
  if (!secret) throw createError({ statusCode: 500, statusMessage: "Server misconfigured" });

  const raw = await readRawBody(event);
  if (!raw) throw createError({ statusCode: 400, statusMessage: "Missing body" });
  // getHeaders → Partial<Record<…, string | undefined>>; svix reads only the svix-* string
  // headers, so widen to the Record<string, string> its verify() signature expects.
  const headers = getHeaders(event) as Record<string, string>;

  let clerkEvent: ClerkUserEvent;
  try {
    clerkEvent = new Webhook(secret).verify(raw, headers) as ClerkUserEvent;
  } catch {
    throw createError({ statusCode: 403, statusMessage: "Invalid signature" });
  }

  if (USER_EVENTS.has(clerkEvent.type)) await recordClerkEvent(db, clerkEvent);
  return { ok: true };
});

import { drizzle } from "drizzle-orm/postgres-js";
import postgres from "postgres";

// Serverless: one connection per (short-lived) instance; Neon's pooler multiplexes.
export const sql = postgres(process.env.DATABASE_URL!, { prepare: false, max: 1 });
export const db = drizzle(sql);

import { drizzle } from "drizzle-orm/postgres-js";
import postgres from "postgres";

// Long-running process: a real, reused pool. Still prepare:false on the pooled endpoint.
export const sql = postgres(process.env.DATABASE_URL!, { prepare: false, max: 10, idle_timeout: 20 });
export const db = drizzle(sql);

import { neon } from "@neondatabase/serverless";
import { drizzle } from "drizzle-orm/neon-http";

// Edge/Workers have NO TCP sockets, so postgres-js cannot run here. Neon's HTTP
// driver speaks Postgres over fetch — the only client that works on Workers.
export const sql = neon(process.env.DATABASE_URL!);
export const db = drizzle(sql);