feat: initial version

files/src/app.ts

@@ -0,0 +1,11 @@
+import { IConfigService } from "./config/config.interface";
+import { ConfigService } from "./config/config.service";
+
+class App {
+  config: IConfigService;
+  constructor() {
+    this.config = new ConfigService();
+  }
+}
+
+const app = new App();

files/src/config/config.interface.ts

@@ -0,0 +1,3 @@
+export interface IConfigService {
+  get(key: string): string;
+}

files/src/config/config.service.ts

@@ -0,0 +1,27 @@
+import { config, DotenvParseOutput } from "dotenv";
+import { IConfigService } from "./config.interface";
+
+export class ConfigService implements IConfigService {
+  private config: DotenvParseOutput;
+  constructor() {
+    const { error, parsed } = config();
+    if (error) {
+      throw new Error(".env file not found");
+    }
+
+    if (!parsed) {
+      throw new Error("Invalid .env file");
+    }
+
+    this.config = parsed;
+  }
+
+  get(key: string): string {
+    const res = this.config[key];
+    if (!res) {
+      throw new Error(`Key ${key} not found`);
+    }
+
+    return res;
+  }
+}