chore: add eslint and prettier

.prettierignore

@@ -0,0 +1,3 @@
+dist
+node_modules
+

.prettierrc.json

@@ -0,0 +1,8 @@
+{
+  "singleQuote": true,
+  "semi": true,
+  "tabWidth": 2,
+  "printWidth": 80,
+  "trailingComma": "es5"
+}
+

README.md

@@ -30,11 +30,20 @@ API gateway, usage metering, and billing services for the Callora API marketplac
 
 ## Scripts
 
-| Command        | Description                    |
-|----------------|--------------------------------|
-| `npm run dev`  | Run with tsx watch (no build)  |
-| `npm run build`| Compile TypeScript to `dist/`  |
-| `npm start`    | Run compiled `dist/index.js`   |
+| Command            | Description                          |
+| ------------------ | ------------------------------------ |
+| `npm run dev`      | Run with tsx watch (no build)        |
+| `npm run build`    | Compile TypeScript to `dist/`        |
+| `npm start`        | Run compiled `dist/index.js`         |
+| `npm run lint`     | Run ESLint on `src/`                 |
+| `npm run lint:fix` | Auto-fix ESLint issues               |
+| `npm run format`   | Format `src/` + README with Prettier |
+
+## Linting and formatting
+
+- `npm run lint` runs ESLint on `src/`
+- `npm run lint:fix` applies ESLint auto-fixes
+- `npm run format` formats files with Prettier
 
 ## Project layout
 

eslint.config.js

@@ -0,0 +1,57 @@
+import tsParser from '@typescript-eslint/parser';
+import tsPlugin from '@typescript-eslint/eslint-plugin';
+import prettierPlugin from 'eslint-plugin-prettier';
+import prettierConfig from 'eslint-config-prettier';
+import eslintJs from '@eslint/js';
+
+const globals = {
+  console: 'readonly',
+  process: 'readonly',
+  Buffer: 'readonly',
+  setImmediate: 'readonly',
+  clearImmediate: 'readonly',
+  setInterval: 'readonly',
+  clearInterval: 'readonly',
+  setTimeout: 'readonly',
+  clearTimeout: 'readonly',
+  describe: 'readonly',
+  it: 'readonly',
+  test: 'readonly',
+  expect: 'readonly',
+  beforeAll: 'readonly',
+  afterAll: 'readonly',
+  beforeEach: 'readonly',
+  afterEach: 'readonly',
+  jest: 'readonly',
+};
+
+export default [
+  {
+    ignores: ['dist/**', 'node_modules/**'],
+  },
+  eslintJs.configs.recommended,
+  {
+    files: ['src/**/*.ts'],
+    languageOptions: {
+      parser: tsParser,
+      ecmaVersion: 2022,
+      sourceType: 'module',
+      globals,
+    },
+    plugins: {
+      '@typescript-eslint': tsPlugin,
+      prettier: prettierPlugin,
+    },
+    rules: {
+      ...tsPlugin.configs.recommended.rules,
+      ...prettierConfig.rules,
+      'prettier/prettier': [
+        'error',
+        {
+          singleQuote: true,
+          semi: true,
+        },
+      ],
+    },
+  },
+];

package.json

@@ -6,22 +6,28 @@
     "build": "tsc",
     "start": "node dist/index.js",
     "dev": "tsx watch src/index.ts",
-    "lint": "eslint . --ext .ts",
+    "lint": "eslint \"src/**/*.ts\"",
+    "lint:fix": "npm run lint -- --fix",
+    "format": "prettier --write \"src/**/*.ts\" \"README.md\"",
     "typecheck": "tsc --noEmit",
     "test": "jest --runInBand"
   },
   "dependencies": {
     "express": "^4.18.2"
   },
   "devDependencies": {
+    "@eslint/js": "^9.0.0",
     "@types/express": "^4.17.21",
     "@types/jest": "^30.0.0",
     "@types/node": "^20.10.0",
     "@types/supertest": "^6.0.3",
     "@typescript-eslint/eslint-plugin": "^8.56.1",
     "@typescript-eslint/parser": "^8.56.1",
     "eslint": "^10.0.2",
+    "eslint-config-prettier": "^10.0.0",
+    "eslint-plugin-prettier": "^5.2.1",
     "jest": "^30.2.0",
+    "prettier": "^3.5.0",
     "supertest": "^7.2.2",
     "ts-jest": "^29.4.6",
     "tsx": "^4.7.0",

src/index.test.ts

@@ -1,5 +1,4 @@
 import request from 'supertest';
-import express from 'express';
 import app from './index';
 
 describe('Health API', () => {
@@ -8,4 +7,4 @@ describe('Health API', () => {
     expect(response.status).toBe(200);
     expect(response.body.status).toBe('ok');
   });
-});
+});

src/index.ts

@@ -23,4 +23,4 @@ if (process.env.NODE_ENV !== 'test') {
   });
 }
 
-export default app;
+export default app;