helton/header.ejs

## header.ejs
<!DOCTYPE html>
<html lang="en">
<head>
  <title>Meu Dinheiro</title>
  <link href="https://fonts.googleapis.com/css?family=Raleway:400,700" rel="stylesheet">
  <link rel="stylesheet" href="css/styles.css">
</head>
<body style="margin: 0">
  <section class="header">
    <img src="/images/meu-dinheiro.png">
    <ul>
      <li><a href="/">Home</a></li>
      <li><a href="/calculadora">Calculadora</a></li>
      <li><a href="/operacoes">Operações</a></li>
      <li><a href="/operacoes-entrada">Operações de Entrada</a></li>
      <li><a href="/operacoes-saida">Operações de Saída</a></li>
      <li><a href="/nova-operacao">Nova Operação</a></li>
    </ul>
  </section>

  <section class="content">

## index.js
require('dotenv').config()

const express = require('express')
const path = require('path')
const bodyParser = require('body-parser')
const MongoClient = require('mongodb').MongoClient

const app = express()

const port = 3000
const mongoUri = `mongodb://${process.env.MONGO_DB_USER}:${process.env.MONGO_DB_PASSWORD}@${process.env.MONGO_DB_HOST_NODE_01},${process.env.MONGO_DB_HOST_NODE_02},${process.env.MONGO_DB_HOST_NODE_03}/${process.env.MONGO_DB_NAME}?ssl=${process.env.MONGO_DB_SSL}&replicaSet=${process.env.MONGO_DB_REPLICA_SET}&authSource=${process.env.MONGO_DB_AUTH_SOURCE}`

const functions = {
  formatCurrency: currency => {
    let formatter = new Intl.NumberFormat('pt-BR', {
      style: 'currency',
      currency: 'BRL'
    })

    // Contornando o problema do separador decimal não ser exibido corretamente
    return (
      formatter
        .format(currency)
        .replace(/\./g, '#')
        .replace(/,/g, '.')
        .replace(/#/g, ',')
    )
  },
  sum: (collection, fn) => collection.reduce((acc, val) => acc + fn(val), 0)
}

const render = (response, view, data={}) => {
  response.render(view, Object.assign(data, { functions }))
}

app.use(bodyParser.json())
app.use(bodyParser.urlencoded({ extended: true }))

app.use(express.static('public'))
app.set('views', path.join(__dirname, 'views'))
app.set('view engine', 'ejs')

app.get('/', (req, res) => {
  render(res, 'home')
})

app.get('/calculadora', (req, res) => {
  const calculoJuros = (p, i, n) => p * Math.pow(1 + i, n)

  const resultado = {
    calculado: false
  }
  if (req.query.valorInicial && req.query.taxa && req.query.tempo) {
    resultado.calculado = true
    resultado.total = calculoJuros(
      parseFloat(req.query .valorInicial),
      parseFloat(req.query.taxa/100),
      parseInt(req.query.tempo)
    )
  }
  render(res, 'calculadora', { resultado })
})

const findAll = (db, collectionName) => {
  const collection = db.collection(collectionName)
  const cursor = collection.find({})
  const documents = []
  return new Promise((resolve, reject) => {
    cursor.forEach(
      doc => documents.push(doc),
      () => resolve(documents)
    )
  })
}

const insert = (db, collectionName, doc) => {
  const collection = db.collection(collectionName)
  return new Promise((resolve, reject) => {
    collection.insert(doc, (err, res) => err ? reject(err) : resolve(res))
  })
}

app.get('/operacoes', async (req, res) => {
  const operacoes = await findAll(app.db, 'operacoes')
  render(res, 'operacoes', { titulo: 'Todas', operacoes, functions })
})

app.get('/operacoes-entrada', async (req, res) => {
  const todasOperacoes = await findAll(app.db, 'operacoes')
  const operacoes = todasOperacoes.filter(o => o.valor >= 0)
  render(res, 'operacoes', { titulo: 'Entradas', operacoes, functions })
})

app.get('/operacoes-saida', async (req, res) => {
  const todasOperacoes = await findAll(app.db, 'operacoes')
  const operacoes = todasOperacoes.filter(o => o.valor < 0)
  render(res, 'operacoes', { titulo: 'Saídas', operacoes, functions })
})

app.get('/nova-operacao', (req, res) => {
  render(res, 'nova-operacao')
})

app.post('/nova-operacao', async (req, res) => {
  const descricao = req.body.descricao,
        valor     = parseFloat(req.body.valor)
  const operacao = { descricao, valor }

  try {
    const result = await insert(app.db, 'operacoes', operacao)
    console.log(result)
    res.redirect('/operacoes')
  } catch (ex) {
    console.error(ex)
    res.redirect('/')
  }
})

MongoClient.connect(mongoUri, (err, db) => {
  if (err) {
    console.error(err)
  } else {
    app.db = db
    app.listen(port, () => console.log(`Servidor rodando na porta ${port}...`))
  }
})

## operacoes.ejs
<% include header %>
  <h2>Operações - <%= titulo %></h2>

  <table>
    <thead>
      <tr>
        <th>Descrição</th>
        <th>Valor</th>
      </tr>
    </thead>
    <tbody>
      <% operacoes.forEach(operacao => { %>
        <tr>
          <td><%= operacao.descricao %></td>
          <td class="currency"><%= functions.formatCurrency(operacao.valor) %></td>
        </tr>
      <% }) %>
    <tbody>
    <tfoot>
      <tr>
        <td>Total</td>
        <td class="currency"><%= functions.formatCurrency(functions.sum(operacoes, ({valor}) => valor)) %></td>
      </tr>
    </tfoot>
  </table>

<% include footer %>
	require('dotenv').config()

	const express = require('express')
	const path = require('path')
	const bodyParser = require('body-parser')
	const MongoClient = require('mongodb').MongoClient

	const app = express()

	const port = 3000
	const mongoUri = `mongodb://${process.env.MONGO_DB_USER}:${process.env.MONGO_DB_PASSWORD}@${process.env.MONGO_DB_HOST_NODE_01},${process.env.MONGO_DB_HOST_NODE_02},${process.env.MONGO_DB_HOST_NODE_03}/${process.env.MONGO_DB_NAME}?ssl=${process.env.MONGO_DB_SSL}&replicaSet=${process.env.MONGO_DB_REPLICA_SET}&authSource=${process.env.MONGO_DB_AUTH_SOURCE}`

	const functions = {
	formatCurrency: currency => {
	let formatter = new Intl.NumberFormat('pt-BR', {
	style: 'currency',
	currency: 'BRL'
	})

	// Contornando o problema do separador decimal não ser exibido corretamente
	return (
	formatter
	.format(currency)
	.replace(/\./g, '#')
	.replace(/,/g, '.')
	.replace(/#/g, ',')
	)
	},
	sum: (collection, fn) => collection.reduce((acc, val) => acc + fn(val), 0)
	}

	const render = (response, view, data={}) => {
	response.render(view, Object.assign(data, { functions }))
	}

	app.use(bodyParser.json())
	app.use(bodyParser.urlencoded({ extended: true }))

	app.use(express.static('public'))
	app.set('views', path.join(__dirname, 'views'))
	app.set('view engine', 'ejs')

	app.get('/', (req, res) => {
	render(res, 'home')
	})

	app.get('/calculadora', (req, res) => {
	const calculoJuros = (p, i, n) => p * Math.pow(1 + i, n)

	const resultado = {
	calculado: false
	}
	if (req.query.valorInicial && req.query.taxa && req.query.tempo) {
	resultado.calculado = true
	resultado.total = calculoJuros(
	parseFloat(req.query .valorInicial),
	parseFloat(req.query.taxa/100),
	parseInt(req.query.tempo)
	)
	}
	render(res, 'calculadora', { resultado })
	})

	const findAll = (db, collectionName) => {
	const collection = db.collection(collectionName)
	const cursor = collection.find({})
	const documents = []
	return new Promise((resolve, reject) => {
	cursor.forEach(
	doc => documents.push(doc),
	() => resolve(documents)
	)
	})
	}

	const insert = (db, collectionName, doc) => {
	const collection = db.collection(collectionName)
	return new Promise((resolve, reject) => {
	collection.insert(doc, (err, res) => err ? reject(err) : resolve(res))
	})
	}

	app.get('/operacoes', async (req, res) => {
	const operacoes = await findAll(app.db, 'operacoes')
	render(res, 'operacoes', { titulo: 'Todas', operacoes, functions })
	})

	app.get('/operacoes-entrada', async (req, res) => {
	const todasOperacoes = await findAll(app.db, 'operacoes')
	const operacoes = todasOperacoes.filter(o => o.valor >= 0)
	render(res, 'operacoes', { titulo: 'Entradas', operacoes, functions })
	})

	app.get('/operacoes-saida', async (req, res) => {
	const todasOperacoes = await findAll(app.db, 'operacoes')
	const operacoes = todasOperacoes.filter(o => o.valor < 0)
	render(res, 'operacoes', { titulo: 'Saídas', operacoes, functions })
	})

	app.get('/nova-operacao', (req, res) => {
	render(res, 'nova-operacao')
	})

	app.post('/nova-operacao', async (req, res) => {
	const descricao = req.body.descricao,
	valor = parseFloat(req.body.valor)
	const operacao = { descricao, valor }

	try {
	const result = await insert(app.db, 'operacoes', operacao)
	console.log(result)
	res.redirect('/operacoes')
	} catch (ex) {
	console.error(ex)
	res.redirect('/')
	}
	})

	MongoClient.connect(mongoUri, (err, db) => {
	if (err) {
	console.error(err)
	} else {
	app.db = db
	app.listen(port, () => console.log(`Servidor rodando na porta ${port}...`))
	}
	})
	<% include header %>
	<h2>Operações - <%= titulo %></h2>

	<table>
	<thead>
	<tr>
	<th>Descrição</th>
	<th>Valor</th>
	</tr>
	</thead>
	<tbody>
	<% operacoes.forEach(operacao => { %>
	<tr>
	<td><%= operacao.descricao %></td>
	<td class="currency"><%= functions.formatCurrency(operacao.valor) %></td>
	</tr>
	<% }) %>
	<tbody>
	<tfoot>
	<tr>
	<td>Total</td>
	<td class="currency"><%= functions.formatCurrency(functions.sum(operacoes, ({valor}) => valor)) %></td>
	</tr>
	</tfoot>
	</table>

	<% include footer %>