JavaScript & Node.js

1function getUpperCase(str) {
2  return str.toUpperCase();
3}
4function getLowerCase(str) {
5  return str.toLowerCase();
6}
7function getSentenceCase(str) {
8  const lowerStr = getLowerCase(str);
9  return lowerStr.charAt(0).toUpperCase() + lowerStr.slice(1);
10}
11function getProperCase(str) {
12  const properCaseArr = str.split(" ").map((word) => getSentenceCase(word));
13  return properCaseArr.join(" ");
14}
15module.exports = {
16  getProperCase,
17  getLowerCase,
18  getUpperCase,
19  getSentenceCase,
20};

1function isPrime(n) {
2  if (!Number.isInteger(n) || n < 2) return false;
3  if (n < 4) return true;
4  if (n % 2 === 0 || n % 3 === 0) return false;
5  for (let i = 5; i * i <= n; i += 6) {
6    if (n % i === 0 || n % (i + 2) === 0) return false;
7  }
8  return true;
9}
10
11module.exports = { isPrime };

11router.post("/register", async (req, res) => {
12  const { email, password } = req.body;
13  if (!email || !password) {
14    return res.status(400).json({ message: "Email and password are required" });
15  }
16  if (findByEmail(email)) {
17    return res.status(409).json({ message: "Email already in use" });
18  }
19  const passwordHash = await bcrypt.hash(password, 10);
20  const users = readUsers();
21  const newUser = {
22    id: randomUUID(),
23    email,
24    passwordHash,
25    role: "user",
26  };
27  users.push(newUser);
28  writeUsers(users);
29  const token = signToken({
30    id: newUser.id,
31    email: newUser.email,
32    role: newUser.role,
33  });
34  res.status(201).json({ message: "User registered successfully", token });
35});
36
37router.post("/login", async (req, res) => {
38  const { email, password } = req.body;
39  if (!email || !password) {
40    return res.status(400).json({ message: "Email and password are required" });
41  }
42  const user = findByEmail(email);
43  if (!user) {
44    return res.status(401).json({ message: "Invalid credentials" });
45  }
46  const match = await bcrypt.compare(password, user.passwordHash);
47  if (!match) {
48    return res.status(401).json({ message: "Invalid credentials" });
49  }
50  const token = signToken({ id: user.id, email: user.email, role: user.role });
51  res.json({ message: "Login successful", token });
52});

30app.post("/transfer", async (req, res) => {
31  const { fromId, toId, amount } = req.body;
32  if (!fromId || !toId || !amount) {
33    const err = new Error("Missing required fields: fromId, toId, amount");
34    err.status = 400;
35    throw err;
36  }
37  if (amount <= 0) {
38    const err = new Error("Transfer amount must be positive");
39    err.status = 400;
40    throw err;
41  }
42  const accounts = await getAccounts();
43  const sender = accounts.find((a) => a.id === fromId);
44  if (!sender) {
45    const err = new Error("Sender account not found");
46    err.status = 404;
47    throw err;
48  }
49  const recipient = accounts.find((a) => a.id === toId);
50  if (!recipient) {
51    const err = new Error("Recipient account not found");
52    err.status = 404;
53    throw err;
54  }
55  if (sender.balance < amount) {
56    const err = new Error("Insufficient funds");
57    err.status = 409;
58    throw err;
59  }
60  sender.balance -= amount;
61  recipient.balance += amount;
62  await saveAccounts(accounts);
63  res.json({
64    message: "Transfer successful",
65    senderName: sender.owner,
66    recipientName: recipient.owner,
67    amountTransferred: amount,
68    senderNewBalance: sender.balance,
69    recipientNewBalance: recipient.balance,
70  });
71});

1const assert = require("node:assert/strict");
2const caseConverter = require("./index");
3assert.strictEqual(
4  caseConverter.getUpperCase("hello free Code Camp!"),
5  "HELLO FREE CODE CAMP!",
6);
7assert.strictEqual(
8  caseConverter.getLowerCase("hello free Code Camp!"),
9  "hello free code camp!",
10);
11assert.strictEqual(
12  caseConverter.getProperCase("hello free Code Camp!"),
13  "Hello Free Code Camp!",
14);
15assert.strictEqual(
16  caseConverter.getSentenceCase("hello free Code Camp!"),
17  "Hello free code camp!",
18);