[app/server] Introduce a test for creating a user document in the database

* introduce a test on the server to see if user creation works (backend process <-> db only;
  still needs a test that involves the router, too)
* main server process is no connection-aware and wont start if database is not reachable
* some renaming, cause it's more descriptive
* unify quote usage

app/server/dev.env

+PORT=3000
+MONGODB_URL=mongodb://localhost:27017/todo-app
+JWT_SECRET=myjwtsecret

app/server/jest.config.js

+module.exports = {
+    testEnvironment: 'node'
+};

app/server/package.json

@@ -5,10 +5,13 @@
   "license": "MIT",
   "scripts": {
     "start": "node src/index",
-    "dev": "env-cmd -f ./dev.env nodemon src/index"
+    "dev": "env-cmd -f ./dev.env nodemon src/index",
+    "test": "env-cmd -f ./dev.env jest --ci"
   },
   "devDependencies": {
+    "@shelf/jest-mongodb": "^1.1.5",
     "env-cmd": "^10.1.0",
+    "jest": "^25.1.0",
     "nodemon": "^2.0.2"
   },
   "dependencies": {

app/server/src/db/mongo.js

+const mongoose = require('mongoose');
+
+
+const mongooseInstance_ = mongoose.connect(process.env.MONGODB_URL, {
+    useNewUrlParser: true,
+    useCreateIndex: true,
+    useFindAndModify: false,
+    useUnifiedTopology: true,
+
+    // NOTE: as of the docs `connectTimeoutMS` should be used when `useUnifiedTopology: true`,
+    // but apparently it has no impact what so ever. Instead, the following works ¯\_(ツ)_/¯
+    serverSelectionTimeoutMS: 7000  // 7 sec
+});
+
+
+module.exports = mongooseInstance_;

app/server/src/db/mongoose.js

-const mongoose = require('mongoose')
-
-mongoose.connect(process.env.MONGODB_URL, {
-    useNewUrlParser: true,
-    useCreateIndex: true,
-    useFindAndModify: false,
-    useUnifiedTopology: true
-})
-

app/server/src/index.js

 const path = require( 'path' );
 
-const express = require('express')
-const cors = require('cors')
-const helmet = require('helmet')
-require('./db/mongoose')
-const todoRoutes = require('./routes/todo-routes')
-const userRoutes = require('./routes/user-routes')
-const errorRoutes = require('./routes/error-routes')
-let cookieParser = require('cookie-parser')
-
-const app = express()
-const port = process.env.PORT || 5000
+const express = require('express');
+const cors = require('cors');
+const helmet = require('helmet');
+const dbClientInstance_ = require('./db/mongo.js');
+const todoRoutes = require('./routes/todo');
+const userRoutes = require('./routes/user');
+const errorRoutes = require('./routes/error');
+let cookieParser = require('cookie-parser');
+
+const app = express();
+const port = process.env.PORT || 5000;
 
 const corsOptions = {
     origin: `http://localhost:${ port }`,
     credentials: true
-}
+};
 
-app.use(express.json())
-app.use(cors(corsOptions))
+app.use(express.json());
+app.use(cors(corsOptions));
 
-app.use(cookieParser())
+app.use(cookieParser());
 
-app.use(helmet())
+app.use(helmet());
 app.use(helmet.contentSecurityPolicy({
     directives: {
         defaultSrc: ["'self'"],
         styleSrc: ["'self' 'unsafe-inline'"],
         scriptSrc: ["'self' 'unsafe-inline' 'unsafe-eval'"]
     }
-}))
+}));
 
-app.use(todoRoutes)
-app.use(userRoutes)
+app.use(todoRoutes);
+app.use(userRoutes);
 app.use('/', express.static(path.join(__dirname,`./../../client/build`)));
-app.use(errorRoutes)
-
-app.listen(port, () => {
-    console.log('ToDo server is up on port ' + port)
-})
-
+app.use(errorRoutes);
+
+
+(async function main(){
+    try{
+        const dbClient = await dbClientInstance_;
+        process.on( 'exit', ()=>{
+            dbClient.disconnect();
+        });
+
+        await new Promise( (__ful, rej__ )=>{
+            app.listen(port, function(){
+                console.log( `ToDo server is up on port ${ port }`);
+                __ful();
+            }).on( 'error', rej__);
+        });
+    }catch(e){
+        console.error( new Error( `Cannot connect to database ${ process.env.MONGODB_URL }` ) );
+        process.exit( 1 );
+    }
+})();

app/server/src/middlewares/auth.js

 const jwt = require('jsonwebtoken')
-const Users = require('../models/Users-model')
+const { model: Users } = require('../models/Users')
 
 const auth = async (req, res, next) => {
     try {

app/server/src/models/Todos-model.js → app/server/src/models/Todos.js

-const mongoose = require("mongoose")
+const mongoose = require('mongoose');
 
-const ToDosSchema = new mongoose.Schema({
+
+const schema = new mongoose.Schema({
     title: {
         type: String,
         required: true,
@@ -23,9 +24,9 @@ const ToDosSchema = new mongoose.Schema({
     }
 }, {
     timestamps: true
-})
+});
 
-const ToDos = mongoose.model('ToDos', ToDosSchema)
+const model = mongoose.model( 'ToDos', schema );
 
-module.exports = ToDos
 
+module.exports = { schema, model };

app/server/src/models/Uers.test.js

+const dbClientInstance_ = require( './../db/mongo.js' );
+
+const { model: Users } = require( './Users.js' );
+
+
+describe( 'Model: Users', ()=>{
+    beforeAll( async ()=>{
+        await dbClientInstance_;
+    });
+
+
+    const userData = {
+        name: 'myname',
+        email: 'myname@example.com',
+        password: 'mypassword'
+    };
+
+    test( 'creating a user', async ()=>{
+        const userData = {
+            name: 'myname',
+            email: 'myname@example.com',
+            password: 'mypassword'
+        };
+
+        const userDoc = await Users( userData );
+        await userDoc.save();
+
+        const userRecord = await Users.findOne({ email: userData.email });
+
+        const { password, ...userInfo } = userData;
+
+        expect( userRecord ).toEqual( expect.objectContaining( userInfo ) );
+    });
+
+
+    afterAll( async ()=>{
+        const dbClient = await dbClientInstance_;
+        const { connection } = dbClient;
+        await connection.dropDatabase();
+        await dbClient.disconnect();
+    });
+});

app/server/src/models/Users-model.js → app/server/src/models/Users.js

-const mongoose = require("mongoose")
-const validator = require('validator')
-const bcrypt = require('bcryptjs')
-const jwt = require('jsonwebtoken')
+const mongoose = require('mongoose');
+const validator = require('validator');
+const bcrypt = require('bcryptjs');
+const jwt = require('jsonwebtoken');
 
-const usersSchema = new mongoose.Schema({
+
+const schema = new mongoose.Schema({
     name: {
         type: String,
         required: true,
@@ -16,7 +17,7 @@ const usersSchema = new mongoose.Schema({
         required: true,
         validate(value) {
             if (!validator.isEmail(value)) {
-                throw new Error("Invalid email format")
+                throw new Error('Invalid email format');
             }
         }
     },
@@ -34,59 +35,58 @@ const usersSchema = new mongoose.Schema({
     }]
 }, {
     timestamps: true
-})
+});
 
-usersSchema.pre('save', async function (next) {
-    const user = this
+schema.pre('save', async function (next) {
+    const user = this;
 
     if (user.isModified('password')) {
-        user.password = await bcrypt.hash(user.password, 8)
+        user.password = await bcrypt.hash(user.password, 8);
     }
 
-    next()
-})
-
+    next();
+});
 
-usersSchema.statics.findByCredentials = async (email, password) => {
-    const user = await Users.findOne({ email })
+schema.statics.findByCredentials = async (email, password) => {
+    const user = await Users.findOne({ email });
 
     if (!user) {
-        throw new Error('Unable to login')
+        throw new Error('Unable to login');
     }
 
-    const isMatch = await bcrypt.compare(password, user.password)
+    const isMatch = await bcrypt.compare(password, user.password);
 
     if (!isMatch) {
-        throw new Error('Unable to login')
+        throw new Error('Unable to login');
     }
 
-    return user
-}
+    return user;
+};
 
-usersSchema.methods.generateAuthToken = async function () {
+schema.methods.generateAuthToken = async function () {
 
-    const user = this
+    const user = this;
 
-    const token = jwt.sign({ _id: user._id.toString() }, process.env.JWT_SECRET)
+    const token = jwt.sign({ _id: user._id.toString() }, process.env.JWT_SECRET);
 
-    user.tokens = user.tokens.concat({ token })
+    user.tokens = user.tokens.concat({ token });
 
-    await user.save()
+    await user.save();
 
-    return token
-}
+    return token;
+};
 
-usersSchema.methods.toJSON = function () {
-    const user = this
-    const publicUserData = user.toObject()
+schema.methods.toJSON = function () {
+    const user = this;
+    const publicUserData = user.toObject();
 
-    delete publicUserData.password
-    delete publicUserData.tokens
+    delete publicUserData.password;
+    delete publicUserData.tokens;
 
     return publicUserData
 }
 
-const Users = mongoose.model('Users', usersSchema)
+const model = mongoose.model( 'Users', schema );
 
-module.exports = Users
 
+module.exports = { schema, model };

app/server/src/routes/error-routes.js → app/server/src/routes/error.js

@@ -6,7 +6,7 @@ routes.get('*', async (req, res) => {
     try {
 
         res.status(404).send({
-            error: "Invalid endpoint."
+            error: 'Not Found'
         })
     }
     catch (e) {
@@ -15,4 +15,4 @@ routes.get('*', async (req, res) => {
 })
 
 
-module.exports = routes
\ No newline at end of file
+module.exports = routes

app/server/src/routes/todo-routes.js → app/server/src/routes/todo.js

 const express = require('express')
-const ToDos = require('../models/Todos-model')
+const { model: ToDos } = require('../models/Todos')
 const auth = require('../middlewares/auth')
 const routes = express.Router()
 
@@ -53,11 +53,11 @@ routes.patch('/todo/update', auth, async (req, res) => {
         return res.status(400).send({ error: 'Invalid fields to update!' })
     }
     const updateObj = {}
-    if (changedTodo.hasOwnProperty("important")) {
+    if (changedTodo.hasOwnProperty('important')) {
         updateObj.important = changedTodo.important
     }
 
-    if (changedTodo.hasOwnProperty("done")) {
+    if (changedTodo.hasOwnProperty('done')) {
         updateObj.done = changedTodo.done
     }
 

app/server/src/routes/user-routes.js → app/server/src/routes/user.js

 const express = require('express')
-const Users = require('../models/Users-model')
+const { model: Users } = require('../models/Users')
 const auth = require('../middlewares/auth')
 const routes = express.Router()
 
@@ -77,4 +77,4 @@ routes.post('/logout', auth, async (req, res) => {
     }
 })
 
-module.exports = routes
\ No newline at end of file
+module.exports = routes