feat: basic code and configurations

src/call/call.test.ts

@@ -0,0 +1,9 @@
+import { formatResponse } from './call';
+
+describe('call', () => {
+  it('returns the formatted response string', async () => {
+    const response = formatResponse('test');
+
+    expect(response).toBe('This is the string from GET: test');
+  });
+});

src/call/call.ts

@@ -0,0 +1,8 @@
+/**
+ * Format a response message containing a user input.
+ * @param string - The user input string.
+ * @returns The formatted message.
+ */
+export function formatResponse(str: string) {
+  return `This is the string from GET: ${str}`;
+}

src/index.ts

@@ -0,0 +1,16 @@
+import express, { Request, Response } from 'express';
+import { formatResponse } from './call/call';
+
+const app = express();
+
+app.get('/', (req: Request, res: Response) => {
+  if (!req.query.string) {
+    return res.status(400).send('Missing query parameter: str');
+  }
+
+  return res.send(formatResponse(req.query.string as string));
+});
+
+app.listen(3000, () => {
+  console.log('Server running on port 3000');
+});