Merge pull request #1 from victorbadaro/feature/crud-users

Methods to find, create, update and delete users

Author: Victor Badaró

src/config/database.js

@@ -1,9 +1,11 @@
 import { Pool } from 'pg';
 
-const databaseConfig = new Pool({
+const connection = new Pool({
     host: process.env.DB_HOST,
     port: process.env.DB_PORT,
     user: process.env.DB_USERNAME,
     password: process.env.DB_PASSWORD,
     database: process.env.DB_DATABASE
-});
+});
+
+export { connection };

src/controllers/UserController.js

@@ -0,0 +1,67 @@
+import User from '../models/User';
+
+class UserController {
+    async index(request, response) {
+        const users = await User.find();
+
+        return response.json(users);
+    }
+
+    async find(request, response) {
+        const { id } = request.params;
+        const result = await User.find({ where: { id } });
+        const user = result[0];
+
+        if (!user)
+            return response.status(400).json({ error: 'User not found!' });
+
+        return response.json(user);
+    }
+
+    async create(request, response) {
+        const { name, email } = request.body;
+        const result = await User.find({ where: { email } });
+        const userFoundByEmail = result[0];
+
+        if (userFoundByEmail)
+            return response.status(400).json({ error: 'Email already exists!' });
+
+        const user = await User.create({ name, email });
+
+        return response.status(201).json(user);
+    }
+
+    async update(request, response) {
+        const { id } = request.params;
+        const { name, email } = request.body;
+        let result = await User.find({ where: { id: Number(id) } });
+        const user = result[0];
+
+        if (!user)
+            return response.status(400).json({ error: 'User not found!' });
+
+        result = await User.find({ where: { email } });
+        const userFoundByEmail = result[0];
+
+        if (userFoundByEmail && userFoundByEmail.id !== Number(id))
+            return response.status(400).json({ error: 'Email already exists!' });
+
+        await User.update({ name, email }, { where: { id } });
+
+        return response.status(204).send();
+    }
+
+    async delete(request, response) {
+        const { id } = request.params;
+        const result = await User.find({ where: { id } });
+        const user = result[0];
+
+        if (!user)
+            return response.status(400).json({ error: 'User not found!' });
+
+        await User.delete({ where: { id } });
+        return response.status(204).send();
+    }
+}
+
+export default new UserController();

src/models/User.js

@@ -0,0 +1,95 @@
+import { connection as database } from '../config/database';
+
+class User {
+    async find(filters) {
+        let query = 'SELECT * FROM users';
+
+        if (filters)
+            Object.keys(filters).forEach(filter => {
+                query += ` ${filter}`;
+
+                Object.keys(filters[filter]).forEach(field => {
+                    if (filters[filter][field] !== null)
+                        query += ` ${field} = '${filters[filter][field]}'`;
+                    else
+                        query += ` ${field} = null`;
+                });
+            });
+
+        const result = await database.query(query);
+        const users = result.rows;
+
+        return users;
+    }
+
+    async create(data) {
+        const fields = [];
+        const values = [];
+
+        Object.keys(data).forEach(field => {
+            fields.push(field);
+
+            if (data[field] !== null) {
+                if (Array.isArray(data[field])) {
+                    const newArray = data[field].map(item => `'${item}'`);
+
+                    values.push(`ARRAY[${newArray}]`);
+                } else
+                    values.push(`'${data[field]}'`);
+            } else
+                values.push('null');
+        });
+
+        const query = `INSERT INTO users (${fields.join(', ')}) VALUES (${values.join(', ')}) RETURNING *`;
+        const result = await database.query(query);
+        const user = result.rows[0];
+
+        return user;
+    }
+
+    async update(data, filters) {
+        const fieldsToUpdate = [];
+
+        Object.keys(data).forEach(field => {
+            fieldsToUpdate.push(`${field} = '${data[field]}'`);
+        });
+
+        let query = `UPDATE users SET ${fieldsToUpdate.join(', ')}`;
+
+        if (filters)
+            Object.keys(filters).forEach(filter => {
+                query += ` ${filter.toUpperCase()}`;
+
+                Object.keys(filters[filter]).forEach(field => {
+                    if (filters[filter][field] !== null)
+                        query += ` ${field} = '${filters[filter][field]}'`;
+                    else
+                        query += ` ${field} = null`;
+                });
+            });
+
+        await database.query(query);
+        return;
+    }
+
+    async delete(filters) {
+        let query = 'DELETE FROM users';
+
+        if (filters)
+            Object.keys(filters).forEach(filter => {
+                query += ` ${filter.toUpperCase()}`;
+
+                Object.keys(filters[filter]).forEach(field => {
+                    if (filters[filter][field] !== null)
+                        query += ` ${field} = '${filters[filter][field]}'`;
+                    else
+                        query += ` ${field} = null`;
+                });
+            });
+
+        await database.query(query);
+        return;
+    }
+}
+
+export default new User();

src/routes/index.js

@@ -1,5 +1,8 @@
 import { Router } from 'express';
+import { router as usersRouter } from './usersRoutes';
 
 const router = Router();
 
+router.use('/users', usersRouter);
+
 export { router };

src/routes/usersRoutes.js

@@ -0,0 +1,12 @@
+import { Router } from 'express';
+import UserController from '../controllers/UserController';
+
+const router = Router();
+
+router.get('/', UserController.index);
+router.post('/', UserController.create);
+router.get('/:id', UserController.find);
+router.put('/:id', UserController.update);
+router.delete('/:id', UserController.delete);
+
+export { router };