# Slim

### Server requirements

* PHP >= 7.2
* Slim >= 4.x

### Install

Install the latest package version by:

```
composer require inspector-apm/inspector-slim
```

### Register On Container

First you have to register the Inspector instance inside the application container in order to make the monitoring agent available within the application.

Consider to use [environment variables](https://github.com/vlucas/phpdotenv) to store your project's INGESTION KEY:

```php
$container->set('inspector', function () {
    $configuration = new \Inspector\Slim\Configuration('INSPECTOR_INGESTION_KEY');
	
    return new \Inspector\Inspector($configuration);
});
```

If you are using a Slim 4 skeleton you can add a new container definition in `app/dependencies.php` file:

```php
use DI\ContainerBuilder;
use Psr\Container\ContainerInterface;

return function (ContainerBuilder $containerBuilder) {
    $containerBuilder->addDefinitions([
    
        // Other services definitions...
    
        'inspector' => function (ContainerInterface $container) {
            $configuration = new \Inspector\Slim\Configuration('INSPECTOR_INGESTION_KEY');
            return new \Inspector\Inspector($configuration);
        }
        
    ]);
}
```

You can get an `INSPECTOR_INGESTION_KEY` creating a new project in your [Inspector](https://www.inspector.dev/) account.

### Attach the middleware

To monitor all the incoming HTTP traffic you can attach the middleware globally:

```php
$app->add(\Inspector\Slim\WebRequestMonitoring::class);
```

Or in specific routes:

```php
$app->get('/home', function () {
    
    // do something...
    
})->add(\Inspector\Slim\WebRequestMonitoring::class);
```

### Test that everything works

Create a test route and open it in the browser <http://localhost:8080>

```php
$app->get('/test', function () {
    
    throw new \Exception('My First Exception.');
    
});
```

You should receive your first notification in a few seconds.

### Add Segments

You can add segments to the transaction's timeline from route functions:

```php
$app->get('/', function (Request $request, Response $response) {
    /*
     * Retrieve the inspector instance from the container.
     */
    $this->get('inspector')->addSegment(function () {
        
        // your code here...
        sleep(1);
        
    }, 'sleep');
        
    return $response;
});
```

If your routes are organized using controllers you need to inject the container in the controller constructor in order to retrieve the inspector agent later during execution:

```php
namespace App\Controllers;


use Psr\Container\ContainerInterface;
use Psr\Http\Message\ResponseInterface as Response;
use Psr\Http\Message\ServerRequestInterface as Request;

class TestRouteController
{
    protected $container;
    
    /**
     * Inject the container to retrieve the inspector instance later.
     */
    public function __construct(ContainerInterface $container)
    {
        $this->container = $container;
    }

    public function __invoke(Request $request, Response $response)
    {
        // Use the inspector instance from the container.
        $this->container->get('inspector')->addSegment(function () {
        
            // your code here...
            sleep(1);
            
        }, 'sleep');

        $response->getBody()->write('Test route.');

        return $response;
    }
}
```

{% hint style="info" %}

### **Learn more about** [**custom segments**](https://docs.inspector.dev/concepts/custom-segments)**.**

{% endhint %}