Add log function

package-lock.json

@@ -12,6 +12,7 @@
         "@owlboard/backend-data-contracts": "^0.0.1"
       },
       "devDependencies": {
+        "@types/node": "^25.0.3",
         "typescript": "^5.9.3"
       }
     },
@@ -21,6 +22,16 @@
       "integrity": "sha512-uUjz/EEdCEnW0is3s1QiFvFfeVk1FcaBVGL+atfwo8lMWqTwQfLwKbG7qZNtvLNp2U8GabDWkf2srM86A20KlA==",
       "license": "ISC"
     },
+    "node_modules/@types/node": {
+      "version": "25.0.3",
+      "resolved": "https://registry.npmjs.org/@types/node/-/node-25.0.3.tgz",
+      "integrity": "sha512-W609buLVRVmeW693xKfzHeIV6nJGGz98uCPfeXI1ELMLXVeKYZ9m15fAMSaUPBHYLGFsVRcMmSCksQOrZV9BYA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "undici-types": "~7.16.0"
+      }
+    },
     "node_modules/typescript": {
       "version": "5.9.3",
       "resolved": "https://registry.npmjs.org/typescript/-/typescript-5.9.3.tgz",
@@ -34,6 +45,13 @@
       "engines": {
         "node": ">=14.17"
       }
+    },
+    "node_modules/undici-types": {
+      "version": "7.16.0",
+      "resolved": "https://registry.npmjs.org/undici-types/-/undici-types-7.16.0.tgz",
+      "integrity": "sha512-Zz+aZWSj8LE6zoxD+xrjh4VfkIG8Ya6LvYkZqtUQGJPZjYl53ypCaUwWqo7eI0x66KBGeRo+mlBEkMSeSZ38Nw==",
+      "dev": true,
+      "license": "MIT"
     }
   }
 }

package.json

@@ -21,6 +21,7 @@
     "@owlboard/backend-data-contracts": "^0.0.1"
   },
   "devDependencies": {
+    "@types/node": "^25.0.3",
     "typescript": "^5.9.3"
   }
 }

src/index.ts

@@ -0,0 +1 @@
+import { log } from './logger'

src/logger.ts

@@ -0,0 +1,39 @@
+type LogLevel = 'DEBUG' | 'INFO' | 'WARN' | 'ERROR';
+const colours: Record<LogLevel, string> = {
+    DEBUG: '\x1b[36m', // Cyan
+    INFO:  '\x1b[32m', // Green
+    WARN:  '\x1b[33m', // Yellow
+    ERROR: '\x1b[31m', // Red
+};
+
+const levelWeight: Record<LogLevel, number> = {
+    DEBUG: 0,
+    INFO: 1,
+    WARN: 2,
+    ERROR: 3,
+};
+
+const RESET = '\x1b[0m';
+
+const CURRENT_LOG_LEVEL = (process.env.LOG_LEVEL as LogLevel) || 'INFO';
+const MIN_WEIGHT = levelWeight[CURRENT_LOG_LEVEL] ?? 1;
+
+export function log(level: LogLevel, msg: string, ...args: any[]): void {
+    // Drop log if below LOG_LEVEL
+    if (levelWeight[level] < MIN_WEIGHT) return;
+
+    const timestamp = new Date().toISOString();
+    const colour = colours[level] || RESET;
+
+    const header = `[${timestamp}] [${colour}${level.padEnd(5)}${RESET}]: ${msg}`;
+
+    if (args.length > 0) {
+        if (level === 'ERROR') {
+            console.error(header, ...args);
+        } else {
+            console.log(header, ...args);
+        }
+    } else {
+        level === 'ERROR' ? console.error(header) : console.log(header);
+    }
+}

tsconfig.json

@@ -7,10 +7,12 @@
 
     // Environment Settings
     // See also https://aka.ms/tsconfig/module
-    "module": "commonjs",
+    "module": "esnext",
-    "target": "es2020",
+    "target": "es2022",
     "esModuleInterop": true,
-    "types": [],
+    "types": ["node"],
+    "moduleResolution": "bundler",
+    "allowSyntheticDefaultImports": true,
     // For nodejs:
     // "lib": ["esnext"],
     // "types": ["node"],