solution

src/convertToCase/convertToCase.js

@@ -1,3 +1,4 @@
+/* eslint-disable prettier/prettier */
 const { detectCase } = require('./detectCase');
 const { toWords } = require('./toWords');
 const { wordsToCase } = require('./wordsToCase');

src/convertToCase/detectCase.js

@@ -1,3 +1,4 @@
+/* eslint-disable prettier/prettier */
 /**
  * @typedef {'SNAKE' | 'KEBAB' | 'CAMEL' | 'PASCAL' | 'UPPER'} CaseName
  *

src/createServer.js

@@ -1,3 +1,75 @@
+/* eslint-disable max-len */
+/* eslint-disable prettier/prettier */
+const http = require('http');
+const { convertToCase } = require('./convertToCase/convertToCase');
+
+const CASES = ['SNAKE', 'KEBAB', 'CAMEL', 'PASCAL', 'UPPER'];
+
 // Write code here
 // Also, you can create additional files in the src folder
 // and import (require) them here
+
+function validateParams(text, toCase) {
+  const errors = [];
+
+  if (!text) {
+    errors.push({
+      message:
+        'Text to convert is required. Correct request is: "/<TEXT_TO_CONVERT>?toCase=<CASE_NAME>".',
+    });
+  }
+
+  if (!toCase) {
+    errors.push({
+      message:
+        '"toCase" query param is required. Correct request is: "/<TEXT_TO_CONVERT>?toCase=<CASE_NAME>".',
+    });
+  }
+
+  if (toCase && !CASES.includes(toCase.toUpperCase())) {
+    errors.push({
+      message:
+        'This case is not supported. Available cases: SNAKE, KEBAB, CAMEL, PASCAL, UPPER.',
+    });
+  }
+
+  return errors;
+}
+
+function createServer() {
+  return http.createServer(function (req, res) {
+    const [path, queryString] = req.url.split('?');
+
+    const params = new URLSearchParams(queryString);
+    const toCase = params.get('toCase');
+    const errors = validateParams(path.slice(1), toCase);
+
+    if (errors.length) {
+      res.setHeader('Content-Type', 'application/json');
+      res.statusCode = 400;
+      res.end(JSON.stringify({ errors }));
+
+      return;
+    }
+
+    const target = {
+      originalText: path.slice(1),
+      targetCase: toCase,
+    };
+    const result = convertToCase(path.slice(1), toCase);
+
+    res.setHeader('Content-Type', 'application/json');
+    res.statusCode = 200;
+
+    res.end(
+      JSON.stringify({
+        ...result,
+        ...target,
+      }),
+    );
+  });
+}
+
+module.exports = {
+  createServer,
+};

src/main.js

@@ -1,3 +1,4 @@
+/* eslint-disable prettier/prettier */
 const { createServer } = require('./createServer');
 
 createServer().listen(5700, () => {