> For the complete documentation index, see [llms.txt](https://favelaware.gitbook.io/favelaware/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://favelaware.gitbook.io/favelaware/9-api/9.8-exemplo-pratico.md).

# 9.8 - Exemplo Prático

Vamos criar um exemplo de API simples 😮

## ⚙️ Exemplo Prático: API com Node.js + Express

### 📦 1. Inicialize o projeto.

Abra a pasta de Documentos do Windows, abra o terminal e digite:

```bash
mkdir Projects
cd Projects
mkdir simple-api
cd simple-api
```

Quando estiver no diretório `C:\Users\SeuNomeDeUsuário\Documents\Projects\simple-api`  escreva o seguinte comando: 

```bash
npm init -y
```

Após a  iniciação do Node.js for concluída,  execute o seguinte comando para instalar o Express:

```bash
npm install express
```

### 📝 2. Crie o arquivo `index.js`

{% code title="index.js" overflow="wrap" %}

```javascript
const express = require('express');
const app = express();

app.use(express.json()); // para aceitar JSON no corpo das requisições

// Dados simulados (em memória)
let users = [
  { id: 1, name: 'Gabbu' },
  { id: 2, name: 'Lia' }
];

// 📥 GET - Buscar todos os usuários
app.get('/users', (req, res) => {
  res.status(200).json(users);
});

// ➕ POST - Criar novo usuário
app.post('/users', (req, res) => {
  const { name } = req.body;
  const newUser = {
    id: users.length + 1,
    name
  };
  users.push(newUser);
  res.status(201).json(newUser);
});

// 🗑️ DELETE - Deletar usuário por ID
app.delete('/users/:id', (req, res) => {
  const userId = parseInt(req.params.id);
  users = users.filter(user => user.id !== userId);
  res.status(204).send();
});

// 🚀 Inicia o servidor
const PORT = 3000;
app.listen(PORT, () => {
  console.log(`API rodando em http://localhost:${PORT}`);
});

```

{% endcode %}

{% hint style="warning" %}
Note que não estamos usando nenhuma estrutura de projeto, colocamos toda a lógica em somente um arquivo!  \
Desafio: Montar essa mesma API no padrão estudado anteriormente.  ☝️🤓
{% endhint %}

### ▶️ 3. Execute a API.

{% code title="bash" %}

```bash
> node index.js
```

{% endcode %}

## 🧪 Testando no Postman

### 🔍 GET `/users`

* Método: `GET`
* URL: `http://localhost:3000/users`
* Retorna todos os usuários.

### ➕ POST `/users`

* Método: `POST`
* URL: `http://localhost:3000/users`
* Body (JSON):

{% code title="" overflow="wrap" fullWidth="false" %}

```json
{
  "name": "Novo Usuário"
}

```

{% endcode %}

👆 Cria um novo usuário.

### ❌ DELETE `/users/:id`

* Método: `DELETE`
* URL: `http://localhost:3000/users/1`
* Remove o usuário com `id = 1`.


---

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