29 scaffold the backend project

AGENTS.md

@@ -4,7 +4,7 @@
 - **Name:** UFOund it
 - **What it is:** UFOund it, is a webapp that displays UFO sightings.
 - **Dataset:** [NUFORC UFO Sightings (Kaggle)](https://www.kaggle.com/datasets/NUFORC/ufo-sightings), CSV, approx 80,000 reports, approx 15mb.
-- **Current state:** The frontend runs on hand-written mock data in `frontend/src/data/`. No backend or database yet.
+- **Current state:** The frontend runs on hand-written mock data in `frontend/src/data/`. The backend is an Apollo Server with only a placeholder `health` query and is not yet connected to the frontend. No database yet.
 - **Course context:** NTNU IT2810 project. Must be reproducible, accessible and sustainable.
 
 ## Tech stack
@@ -30,12 +30,16 @@ npm install
 # Start frontend dev server
 npm run dev
 
-# Start backend
-# TODO: backend not created yet
+# Start backend dev server (GraphQL on http://localhost:3001, restarts on save)
+# Use PORT=3002 npm run dev:backend if port 3001 is taken
+npm run dev:backend
 
-# Build (type-check + production build of the frontend)
+# Build (type-check + production build of frontend and backend)
 npm run build
 
+# Run the built backend (as on the VM)
+npm run start -w backend
+
 # Lint
 npm run lint
 
@@ -61,11 +65,12 @@ frontend/
     types/        Shared TypeScript types
     data/         Mock sightings (to be replaced by GraphQL)
     # graphql/    Planned: Apollo queries
-# backend/        Planned: Node + TypeScript GraphQL server
-#   src/
-#     schema/
-#     resolvers/
-#     db/
+backend/          Node + TypeScript GraphQL server (Apollo Server 5)
+  src/
+    index.ts      Starts the server on PORT (default 3001)
+    schema.ts     GraphQL type definitions and resolvers
+    # db/         Planned: MySQL connection and queries
+  dist/           Build output from `npm run build` (git-ignored)
 # docs/
 ```
 

backend/eslint.config.js

@@ -0,0 +1,23 @@
+import js from '@eslint/js'
+import globals from 'globals'
+import tseslint from 'typescript-eslint'
+import { defineConfig, globalIgnores } from 'eslint/config'
+import eslintConfigPrettier from 'eslint-config-prettier/flat'
+
+// Mirrors frontend/eslint.config.js without the React plugins, and with
+// Node globals instead of browser globals.
+export default defineConfig([
+  globalIgnores(['dist']),
+  {
+    files: ['**/*.ts'],
+    extends: [
+      js.configs.recommended,
+      tseslint.configs.recommended,
+      // Last, so it can turn off any rule that would fight Prettier.
+      eslintConfigPrettier,
+    ],
+    languageOptions: {
+      globals: globals.node,
+    },
+  },
+])

backend/package.json

@@ -0,0 +1,26 @@
+{
+  "name": "backend",
+  "private": true,
+  "version": "0.0.0",
+  "type": "module",
+  "scripts": {
+    "dev": "tsx watch src/index.ts",
+    "build": "tsc -p .",
+    "start": "node dist/index.js",
+    "lint": "eslint ."
+  },
+  "devDependencies": {
+    "@eslint/js": "^10.0.1",
+    "@types/node": "^24.19.1",
+    "eslint": "^10.12.0",
+    "eslint-config-prettier": "^10.1.8",
+    "globals": "^17.13.0",
+    "tsx": "^4.23.15",
+    "typescript": "~6.0.2",
+    "typescript-eslint": "^8.71.0"
+  },
+  "dependencies": {
+    "@apollo/server": "^5.5.1",
+    "graphql": "^16.14.2"
+  }
+}

backend/src/index.ts

@@ -0,0 +1,15 @@
+import { ApolloServer } from '@apollo/server'
+import { startStandaloneServer } from '@apollo/server/standalone'
+import { resolvers, typeDefs } from './schema.ts'
+
+// 3001 is the backend port agreed for the course VM. PORT allows
+// overriding it locally if something else is already using 3001.
+const port = Number(process.env.PORT) || 3001
+
+const server = new ApolloServer({ typeDefs, resolvers })
+
+const { url } = await startStandaloneServer(server, {
+  listen: { port },
+})
+
+console.log(`GraphQL server ready at ${url}`)

backend/src/schema.ts

@@ -0,0 +1,17 @@
+/**
+ * Placeholder schema that only proves the server is running. The real
+ * Sighting types and queries will be agreed on by the group and added
+ * in a separate issue.
+ */
+export const typeDefs = `#graphql
+  type Query {
+    "Returns \\"ok\\" when the server is up."
+    health: String!
+  }
+`
+
+export const resolvers = {
+  Query: {
+    health: () => 'ok',
+  },
+}

backend/tsconfig.json

@@ -0,0 +1,28 @@
+{
+  "compilerOptions": {
+    /* Output: compile src/ to plain JavaScript in dist/ for the VM */
+    "rootDir": "src",
+    "outDir": "dist",
+    "sourceMap": true,
+
+    /* Runtime: Node 20+ with ES modules */
+    "target": "es2023",
+    "lib": ["ES2023"],
+    "module": "nodenext",
+    "types": ["node"],
+    "skipLibCheck": true,
+
+    /* Imports: write `./schema.ts`, emitted as `./schema.js` */
+    "allowImportingTsExtensions": true,
+    "rewriteRelativeImportExtensions": true,
+    "verbatimModuleSyntax": true,
+    "erasableSyntaxOnly": true,
+
+    /* Type checking */
+    "strict": true,
+    "noUnusedLocals": true,
+    "noUnusedParameters": true,
+    "noFallthroughCasesInSwitch": true
+  },
+  "include": ["src"]
+}