Solution

src/controllers/expensesController.js

@@ -0,0 +1,86 @@
+const expensesService = require('../services/expensesService');
+const expensesHelpers = require('../helpers/expense.helper');
+const userHelpers = require('../helpers/user.helper');
+const STATUS_CODE = require('../utils/statusCodes');
+
+const getAll = async (req, res) => {
+  const expenses = await expensesService.getExpenses(req.query);
+
+  res
+    .status(STATUS_CODE.SUCCESS)
+    .send(expenses.map((expense) => expensesHelpers.normalize(expense)));
+};
+
+const getOne = async (req, res) => {
+  const { id } = req.params;
+
+  if (await expensesHelpers.isExpenseExist(id)) {
+    return res
+      .status(STATUS_CODE.NOT_FOUND)
+      .send('Expense with such id not found');
+  }
+
+  const expense = await expensesService.getExpenseById(id);
+
+  res.status(STATUS_CODE.SUCCESS).send(expensesHelpers.normalize(expense));
+};
+
+const create = async (req, res) => {
+  if (await userHelpers.isUserExist(req.body.userId)) {
+    return res.status(STATUS_CODE.BAD_REQUEST).send('User not found');
+  }
+
+  try {
+    expensesHelpers.validateRequestBodyFields(req.body);
+
+    const expense = await expensesService.create(req.body);
+
+    res.statusCode = STATUS_CODE.CREATED;
+
+    res.send(expense);
+  } catch (error) {
+    res.status(STATUS_CODE.BAD_REQUEST).send(error.message);
+  }
+};
+
+const remove = async (req, res) => {
+  const { id } = req.params;
+
+  if (await expensesHelpers.isExpenseExist(id)) {
+    return res
+      .status(STATUS_CODE.NOT_FOUND)
+      .send('Expense with such id not found');
+  }
+
+  await expensesService.remove(id);
+  res.sendStatus(STATUS_CODE.NO_CONTENT);
+};
+
+const update = async (req, res) => {
+  const { id } = req.params;
+  const { title } = req.body;
+
+  if (await expensesHelpers.isExpenseExist(id)) {
+    return res
+      .status(STATUS_CODE.NOT_FOUND)
+      .send('Expense with such id not found');
+  }
+
+  if (typeof title !== 'string') {
+    return res.sendStatus(STATUS_CODE.BAD_REQUEST);
+  }
+
+  const updatedExpense = await expensesService.update({ id, title });
+
+  res
+    .status(STATUS_CODE.SUCCESS)
+    .send(expensesHelpers.normalize(updatedExpense));
+};
+
+module.exports = {
+  getAll,
+  getOne,
+  create,
+  remove,
+  update,
+};

src/controllers/usersController.js

@@ -0,0 +1,82 @@
+const userService = require('../services/usersService');
+const userHelpers = require('../helpers/user.helper');
+const STATUS_CODE = require('../utils/statusCodes');
+
+const getAll = async (_, res) => {
+  const users = await userService.getAll();
+
+  res
+    .status(STATUS_CODE.SUCCESS)
+    .send(users.map((user) => userHelpers.normalize(user)));
+};
+
+const getOne = async (req, res) => {
+  const { id } = req.params;
+
+  if (await userHelpers.isUserExist(id, res)) {
+    return res
+      .status(STATUS_CODE.NOT_FOUND)
+      .send('User with such id not found');
+  }
+
+  const user = await userService.getById(id);
+
+  res.status(STATUS_CODE.SUCCESS).send(userHelpers.normalize(user));
+};
+
+const create = async (req, res) => {
+  const { name } = req.body;
+
+  if (userHelpers.isNameValid(name)) {
+    return res
+      .status(STATUS_CODE.BAD_REQUEST)
+      .send('Error: "name" is required and must be a string.');
+  }
+
+  const user = await userService.create(name);
+
+  res.status(STATUS_CODE.CREATED).send(userHelpers.normalize(user));
+};
+
+const remove = async (req, res) => {
+  const { id } = req.params;
+
+  if (await userHelpers.isUserExist(id, res)) {
+    return res
+      .status(STATUS_CODE.NOT_FOUND)
+      .send('User with such id not found');
+  }
+
+  await userService.remove(id);
+
+  res.sendStatus(STATUS_CODE.NO_CONTENT);
+};
+
+const update = async (req, res) => {
+  const { id } = req.params;
+  const { name } = req.body;
+
+  if (await userHelpers.isUserExist(id, res)) {
+    return res
+      .status(STATUS_CODE.NOT_FOUND)
+      .send('User with such id not found');
+  }
+
+  if (userHelpers.isNameValid(name)) {
+    return res
+      .status(STATUS_CODE.BAD_REQUEST)
+      .send('Error: "name" is required and must be a string.');
+  }
+
+  const updatedUser = await userService.update({ id, name });
+
+  res.status(STATUS_CODE.SUCCESS).send(userHelpers.normalize(updatedUser));
+};
+
+module.exports = {
+  getAll,
+  create,
+  remove,
+  update,
+  getOne,
+};

src/createServer.js

@@ -1,8 +1,21 @@
 'use strict';
 
-const createServer = () => {
-  // your code goes here
-};
+const express = require('express');
+const cors = require('cors');
+
+const { router: usersRouter } = require('./routes/usersRouter');
+const { router: expensesRouter } = require('./routes/expensesRouter');
+
+function createServer() {
+  const app = express();
+
+  app.use(express.json());
+  app.use(cors());
+  app.use('/users', usersRouter);
+  app.use('/expenses', expensesRouter);
+
+  return app;
+}
 
 module.exports = {
   createServer,

src/helpers/expense.helper.js

@@ -0,0 +1,40 @@
+const expenseService = require('../services/expensesService');
+
+const isExpenseExist = async (id) => {
+  if (!(await expenseService.getExpenseById(id))) {
+    return true;
+  }
+};
+
+const validateRequestBodyFields = ({
+  userId,
+  title,
+  amount,
+  isCreatingExpense = true,
+}) => {
+  if (isCreatingExpense && !userId) {
+    throw new Error('provide userId');
+  }
+
+  if (!title || typeof title !== 'string') {
+    throw new Error(
+      'Invalid request: "title" is required and must be a string.',
+    );
+  }
+
+  if (typeof amount !== 'number') {
+    throw new Error('Invalid request: "amount" must be a number.');
+  }
+};
+
+const normalize = ({ dataValues: expense }) => {
+  const { password, ...rest } = expense;
+
+  return rest;
+};
+
+module.exports = {
+  isExpenseExist,
+  validateRequestBodyFields,
+  normalize,
+};

src/helpers/user.helper.js

@@ -0,0 +1,22 @@
+const userService = require('../services/usersService');
+
+const isNameValid = (name) => {
+  return !name || typeof name !== 'string';
+};
+
+const isUserExist = async (id) => {
+  return !(await userService.getById(id));
+};
+
+const normalize = ({ id, name }) => {
+  return {
+    id,
+    name,
+  };
+};
+
+module.exports = {
+  isNameValid,
+  isUserExist,
+  normalize,
+};

src/middleware/errorHandler.js

@@ -0,0 +1,11 @@
+const errorHandler = (action) => async (req, res, next) => {
+  try {
+    await action(req, res, next);
+  } catch (error) {
+    next(error);
+  }
+};
+
+module.exports = {
+  errorHandler,
+};

src/models/Expense.model.js

@@ -1,9 +1,47 @@
 'use strict';
 
+const { DataTypes } = require('sequelize');
 const { sequelize } = require('../db.js');
 
 const Expense = sequelize.define(
-  // your code goes here
+  'Expense',
+  {
+    id: {
+      type: DataTypes.INTEGER,
+      autoIncrement: true,
+      primaryKey: true,
+    },
+    userId: {
+      type: DataTypes.INTEGER,
+      allowNull: false,
+    },
+    spentAt: {
+      type: DataTypes.DATE,
+      allowNull: false,
+      defaultValue: DataTypes.NOW,
+    },
+    title: {
+      type: DataTypes.STRING,
+      allowNull: false,
+    },
+    amount: {
+      type: DataTypes.INTEGER,
+      allowNull: false,
+    },
+    category: {
+      type: DataTypes.STRING,
+      allowNull: true,
+    },
+    note: {
+      type: DataTypes.STRING,
+      allowNull: true,
+    },
+  },
+  {
+    tableName: 'expenses',
+    createdAt: false,
+    updatedAt: false,
+  },
 );
 
 module.exports = {

src/models/User.model.js

@@ -1,9 +1,31 @@
 'use strict';
 
+const { DataTypes } = require('sequelize');
 const { sequelize } = require('../db.js');
 
 const User = sequelize.define(
-  // your code goes here
+  'User',
+  {
+    id: {
+      type: DataTypes.INTEGER,
+      primaryKey: true,
+      autoIncrement: true,
+    },
+    name: {
+      type: DataTypes.STRING,
+      allowNull: false,
+    },
+    createdAt: {
+      type: DataTypes.DATE,
+      allowNull: false,
+      defaultValue: DataTypes.NOW,
+      field: 'created_at',
+    },
+  },
+  {
+    tableName: 'users',
+    updatedAt: false,
+  },
 );
 
 module.exports = {

src/routes/expensesRouter.js

@@ -0,0 +1,19 @@
+const express = require('express');
+const expensesController = require('../controllers/expensesController');
+const { errorHandler } = require('../middleware/errorHandler');
+const router = express.Router();
+
+router
+  .route('/')
+  .get(errorHandler(expensesController.getAll))
+  .post(errorHandler(expensesController.create));
+
+router
+  .route('/:id')
+  .get(errorHandler(expensesController.getOne))
+  .patch(errorHandler(expensesController.update))
+  .delete(errorHandler(expensesController.remove));
+
+module.exports = {
+  router,
+};

src/routes/usersRouter.js

@@ -0,0 +1,18 @@
+const express = require('express');
+const userController = require('../controllers/usersController');
+const { errorHandler } = require('../middleware/errorHandler');
+
+const router = express.Router();
+
+router
+  .route('/')
+  .get(errorHandler(userController.getAll))
+  .post(errorHandler(userController.create));
+
+router
+  .route('/:id')
+  .get(errorHandler(userController.getOne))
+  .delete(errorHandler(userController.remove))
+  .patch(errorHandler(userController.update));
+
+module.exports = { router };