From 22269b5ae920b8797141c9f80a9c3b5169a1c12d Mon Sep 17 00:00:00 2001
From: Taras Demianiuk <demtaras1@gamil.com>
Date: Thu, 16 Apr 2026 12:05:30 +0300
Subject: [PATCH 1/3] added solution

---
 src/createServer.js | 243 +++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 242 insertions(+), 1 deletion(-)

diff --git a/src/createServer.js b/src/createServer.js
index 5b405372..b1add6a4 100644
--- a/src/createServer.js
+++ b/src/createServer.js
@@ -1,11 +1,252 @@
 'use strict';
 
-// const express = require('express');
+const express = require('express');
+const cors = require('cors');
+
+let users = [];
+let expenses = [];
 
 function createServer() {
+  users = [];
+  expenses = [];
+
+  const app = express();
+
+  app.use(express.json());
+  app.use(cors());
+
+  app.get('/users', (req, res) => {
+    res.json(users);
+  });
+
+  app.post('/users', (req, res) => {
+    const { name } = req.body;
+
+    if (!name) {
+      res.sendStatus(400);
+
+      return;
+    }
+
+    const user = { id: users.length + 1, name };
+
+    users.push(user);
+
+    res.statusCode = 201;
+
+    res.send(user);
+  });
+
+  app.get('/users/:id', (req, res) => {
+    const { id } = req.params;
+
+    const user = users.find((userId) => userId.id === Number(id));
+
+    if (!user) {
+      res.sendStatus(404);
+
+      return;
+    }
+
+    res.statusCode = 200;
+
+    res.send(user);
+  });
+
+  app.delete('/users/:id', (req, res) => {
+    const { id } = req.params;
+
+    const userForDelete = users.find((user) => user.id === Number(id));
+
+    if (!userForDelete) {
+      res.sendStatus(404);
+
+      return;
+    }
+
+    const newUsers = users.filter((userId) => userId.id !== Number(id));
+
+    users = newUsers;
+
+    res.sendStatus(204);
+  });
+
+  app.patch('/users/:id', (req, res) => {
+    const { id } = req.params;
+    const { name } = req.body;
+
+    const userForUpdate = users.find((user) => user.id === Number(id));
+
+    if (!userForUpdate) {
+      res.sendStatus(404);
+
+      return;
+    }
+
+    if (!name) {
+      res.sendStatus(400);
+
+      return;
+    }
+
+    userForUpdate.name = name;
+
+    res.statusCode = 200;
+
+    res.send(userForUpdate);
+  });
+
+  app.get('/expenses', (req, res) => {
+    let result = expenses;
+
+    if (req.query.userId) {
+      const userId = Number(req.query.userId);
+
+      result = result.filter((expense) => expense.userId === userId);
+    }
+
+    if (req.query.categories) {
+      result = result.filter(
+        (expense) => expense.category === req.query.categories,
+      );
+    }
+
+    if (req.query.from) {
+      const fromDate = new Date(req.query.from);
+
+      result = result.filter(
+        (expense) => new Date(expense.spentAt) >= fromDate,
+      );
+    }
+
+    if (req.query.to) {
+      const toDate = new Date(req.query.to);
+
+      result = result.filter((expense) => new Date(expense.spentAt) <= toDate);
+    }
+
+    return res.send(result);
+  });
+
+  app.post('/expenses', (req, res) => {
+    const { userId, spentAt, title, amount, category, note } = req.body;
+
+    if (
+      userId == null ||
+      title == null ||
+      amount == null ||
+      category == null ||
+      note == null
+    ) {
+      res.sendStatus(400);
+
+      return;
+    }
+
+    const userExist = users.find((user) => user.id === userId);
+
+    if (!userExist) {
+      res.sendStatus(400);
+
+      return;
+    }
+
+    const expense = {
+      id: expenses.length + 1,
+      userId: Number(userId),
+      spentAt: spentAt || new Date().toISOString(),
+      title: title,
+      amount: amount,
+      category: category,
+      note: note,
+    };
+
+    expenses.push(expense);
+
+    res.statusCode = 201;
+
+    res.send(expense);
+  });
+
+  app.get('/expenses/:id', (req, res) => {
+    const { id } = req.params;
+
+    const expenseById = expenses.find((expense) => expense.id === Number(id));
+
+    if (!expenseById) {
+      res.sendStatus(404);
+
+      return;
+    }
+
+    res.statusCode = 200;
+
+    res.send(expenseById);
+  });
+
+  app.delete('/expenses/:id', (req, res) => {
+    const { id } = req.params;
+
+    const expenseForDelete = expenses.find(
+      (expense) => expense.id === Number(id),
+    );
+
+    if (!expenseForDelete) {
+      res.sendStatus(404);
+
+      return;
+    }
+
+    const newExpenses = expenses.filter((expense) => expense.id !== Number(id));
+
+    expenses = newExpenses;
+
+    res.sendStatus(204);
+  });
+
+  app.patch('/expenses/:id', (req, res) => {
+    const { id } = req.params;
+    const { spentAt, title, amount, category, note } = req.body;
+
+    const expenseForUpdate = expenses.find(
+      (expense) => expense.id === Number(id),
+    );
+
+    if (!expenseForUpdate) {
+      res.sendStatus(404);
+
+      return;
+    }
+
+    if (spentAt !== undefined) {
+      expenseForUpdate.spentAt = spentAt;
+    }
+
+    if (title !== undefined) {
+      expenseForUpdate.title = title;
+    }
+
+    if (amount !== undefined) {
+      expenseForUpdate.amount = amount;
+    }
+
+    if (category !== undefined) {
+      expenseForUpdate.category = category;
+    }
+
+    if (note !== undefined) {
+      expenseForUpdate.note = note;
+    }
+
+    res.statusCode = 200;
+
+    res.send(expenseForUpdate);
+  });
   // Use express to create a server
   // Add a routes to the server
   // Return the server (express app)
+
+  return app;
 }
 
 module.exports = {

From bbb31c759741b8e93f5851d68fd55e1723edb41a Mon Sep 17 00:00:00 2001
From: Taras Demianiuk <demtaras1@gamil.com>
Date: Thu, 16 Apr 2026 12:17:27 +0300
Subject: [PATCH 2/3] added changes from comments

---
 src/createServer.js | 10 ++--------
 1 file changed, 2 insertions(+), 8 deletions(-)

diff --git a/src/createServer.js b/src/createServer.js
index b1add6a4..eb9a3788 100644
--- a/src/createServer.js
+++ b/src/createServer.js
@@ -131,19 +131,13 @@ function createServer() {
   app.post('/expenses', (req, res) => {
     const { userId, spentAt, title, amount, category, note } = req.body;
 
-    if (
-      userId == null ||
-      title == null ||
-      amount == null ||
-      category == null ||
-      note == null
-    ) {
+    if (userId == null || title == null || amount == null || category == null) {
       res.sendStatus(400);
 
       return;
     }
 
-    const userExist = users.find((user) => user.id === userId);
+    const userExist = users.find((user) => user.id === Number(userId));
 
     if (!userExist) {
       res.sendStatus(400);

From a309c5f2967b2bc6f69b23ee45e543427e4d577b Mon Sep 17 00:00:00 2001
From: Taras Demianiuk <demtaras1@gamil.com>
Date: Thu, 16 Apr 2026 12:24:29 +0300
Subject: [PATCH 3/3] added changes

---
 src/createServer.js | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/createServer.js b/src/createServer.js
index eb9a3788..d5cf1bca 100644
--- a/src/createServer.js
+++ b/src/createServer.js
@@ -191,9 +191,11 @@ function createServer() {
       return;
     }
 
-    const newExpenses = expenses.filter((expense) => expense.id !== Number(id));
+    const newListOfExpenses = expenses.filter(
+      (expense) => expense.id !== Number(id),
+    );
 
-    expenses = newExpenses;
+    expenses = newListOfExpenses;
 
     res.sendStatus(204);
   });