feat: setup graphql server with neon relation resolvers

.gitignore

@@ -0,0 +1,2 @@
+node_modules
+.env

index.js

@@ -0,0 +1,99 @@
+const { ApolloServer } = require('@apollo/server');
+const { startStandaloneServer } = require('@apollo/server/standalone');
+const { Pool } = require('pg');
+require('dotenv').config();
+
+// 1. Inisialisasi Pool PostgreSQL
+const pool = new Pool({
+  connectionString: process.env.DATABASE_URL,
+  ssl: {
+    rejectUnauthorized: false,
+  },
+});
+
+// 2. Definisi Schema GraphQL (typeDefs)
+const typeDefs = `#graphql
+  type Category {
+    id: ID!
+    name: String!
+    description: String
+    products: [Product!]!
+  }
+
+  type Product {
+    id: ID!
+    title: String!
+    price: Float!
+    category_id: Int
+    created_by: ID
+    category: Category
+  }
+
+  type Query {
+    categories: [Category!]!
+    category(id: ID!): Category
+    products: [Product!]!
+    product(id: ID!): Product
+  }
+`;
+
+// 3. Definisi Resolver (Query + Nested Resolvers)
+const resolvers = {
+  Query: {
+    categories: async () => {
+      const result = await pool.query('SELECT * FROM categories ORDER BY id ASC');
+      return result.rows;
+    },
+    category: async (_, { id }) => {
+      const result = await pool.query('SELECT * FROM categories WHERE id = $1', [id]);
+      return result.rows[0] || null;
+    },
+    products: async () => {
+      // price di-cast ke float agar cocok dengan tipe Float di GraphQL
+      const result = await pool.query('SELECT id, title, price::float, category_id, created_by FROM products ORDER BY id ASC');
+      return result.rows;
+    },
+    product: async (_, { id }) => {
+      const result = await pool.query('SELECT id, title, price::float, category_id, created_by FROM products WHERE id = $1', [id]);
+      return result.rows[0] || null;
+    },
+  },
+
+  // Resolver Relasi Category -> Products (One-to-Many)
+  Category: {
+    products: async (parent) => {
+      const result = await pool.query(
+        'SELECT id, title, price::float, category_id, created_by FROM products WHERE category_id = $1 ORDER BY id ASC',
+        [parent.id]
+      );
+      return result.rows;
+    },
+  },
+
+  // Resolver Relasi Product -> Category (Many-to-One)
+  Product: {
+    category: async (parent) => {
+      if (!parent.category_id) return null;
+      const result = await pool.query('SELECT * FROM categories WHERE id = $1', [parent.category_id]);
+      return result.rows[0] || null;
+    },
+  },
+};
+
+// 4. Inisialisasi Apollo Server
+const server = new ApolloServer({
+  typeDefs,
+  resolvers,
+  introspection: true, // Wajib aktif untuk Apollo Sandbox publik
+});
+
+// 5. Jalankan Server
+async function startServer() {
+  const port = process.env.PORT || 4000;
+  const { url } = await startStandaloneServer(server, {
+    listen: { port: Number(port) },
+  });
+  console.log(`Server GraphQL siap di: ${url}`);
+}
+
+startServer();

package.json

@@ -0,0 +1,21 @@
+{
+  "name": "week-4",
+  "version": "1.0.0",
+  "description": "",
+  "main": "index.js",
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1",
+    "start": "node index.js"    
+  },
+  "keywords": [],
+  "author": "",
+  "license": "ISC",
+  "type": "commonjs",
+  "dependencies": {
+    "@apollo/server": "^5.5.1",
+    "cors": "^2.8.6",
+    "dotenv": "^17.4.2",
+    "graphql": "^16.14.2",
+    "pg": "^8.23.0"
+  }
+}

test-db.js

@@ -0,0 +1,24 @@
+const { Pool } = require('pg');
+require('dotenv').config();
+
+const pool = new Pool({
+  connectionString: process.env.DATABASE_URL,
+  ssl: {
+    rejectUnauthorized: false,
+  },
+});
+
+async function test() {
+  try {
+    const res = await pool.query('SELECT NOW() AS server_time, COUNT(*) AS total_products FROM products');
+    console.log('Koneksi Sukses!');
+    console.log('Waktu DB Neon:', res.rows[0].server_time);
+    console.log('Jumlah Data Produk:', res.rows[0].total_products);
+  } catch (err) {
+    console.error('Koneksi Gagal:', err.message);
+  } finally {
+    await pool.end();
+  }
+}
+
+test();