README

A robust, production-ready metrics collection library for Laravel 9+ APIs. Effortlessly collect Prometheus-compatible metrics for your API endpoints with zero configuration and seamless integration.

Features

• Zero-configuration setup – Works out of the box with sensible defaults
• Automatic API metrics collection:
  • Request counts by endpoint, method, status, and user
  • Response time histograms for percentile analysis
  • Daily unique user tracking
• Prometheus OpenMetrics format – Standard /metrics endpoint with proper naming conventions
• Multiple storage backends:
  • Redis (recommended for production, requires phpredis extension)
  • InMemory (for testing/development)
• Production-ready – Graceful error handling and lightweight middleware
• Strict Prometheus compliance – All metrics follow Prometheus naming conventions and exposition format

Requirements

• PHP 8.1 or higher
• Laravel 9.0 or higher
• PHP Redis extension (ext-redis) for production use

Quick Start

1. Install

composer require sidcorp-resource/api-metrics-exporter

2. Add Middleware

Add the middleware to your app/Http/Kernel.php:

protected $middlewareGroups = [
    'api' => [
        // ... other middleware
        \SidcorpResource\ApiMetricsExporter\Middleware\MetricsMiddleware::class,
    ],
];

3. View Metrics

Visit http://your-app.com/metrics to see your metrics in Prometheus format.

The library will automatically start collecting metrics using Redis (with InMemory fallback if Redis is unavailable).

Configuration (Optional)

You can customize the default configuration by publishing the config file:

php artisan vendor:publish --provider="SidcorpResource\ApiMetricsExporter\ApiMetricsServiceProvider" --tag="config"

Key configuration options in config/api-metrics.php:

return [
    'driver' => env('API_METRICS_DRIVER', 'redis'),
    'endpoint' => [
        'path' => env('API_METRICS_ENDPOINT_PATH', 'metrics'),
        'middleware' => ['api'],
    ],
    'collection' => [
        'enabled' => env('API_METRICS_ENABLED', true),
        'excluded_paths' => ['health', 'metrics', 'debug*'],
    ],
    'redis' => [
        'connection' => 'default',
        'prefix' => 'api_metrics:',
        'ttl' => 86400,
    ],
];

Securing the /metrics Endpoint

HTTP Basic Authentication

You can enable HTTP Basic Auth for the /metrics endpoint to restrict access:

1. Set the following in your .env file:

   API_METRICS_BASIC_AUTH_ENABLED=true
   API_METRICS_BASIC_AUTH_USERNAME=your_username
   API_METRICS_BASIC_AUTH_PASSWORD=your_password

2. The exporter will require these credentials for all requests to /metrics.

TLS/HTTPS

Note: TLS/HTTPS is handled by your web server (Nginx, Apache, etc.) or Laravel Valet/Homestead. The library does not manage TLS certificates directly.

IP Whitelisting / Network Security

For additional security, you should restrict access to /metrics at the firewall, load balancer, or web server level (e.g. allow-list Prometheus server IPs only).

Prometheus Scrape Config Examples

Basic Auth Example

scrape_configs:
  - job_name: 'my-app'
    metrics_path: '/metrics'
    basic_auth:
      username: 'myuser'      # Must match API_METRICS_BASIC_AUTH_USERNAME
      password: 'mypassword'  # Must match API_METRICS_BASIC_AUTH_PASSWORD
    static_configs:
      - targets: ['myapp.example.com:443']

Usage

Default Metrics

The middleware automatically collects:

• api_requests_total – Total requests by endpoint/method/status/user
• api_request_duration_seconds – Response time histogram
• unique_users_total – Daily unique users per endpoint

Custom Metrics

Currently, the library does not support registering custom drivers, exporters, or decorators via API. These features may be considered for future releases.

Dependency Injection

You can inject the collector into your controller:

use SidcorpResource\ApiMetricsExporter\Contracts\MetricsCollectorInterface;

class CustomController extends Controller
{
    public function __construct(private MetricsCollectorInterface $metrics) {}

    public function index()
    {
        $this->metrics->incrementCounter('custom_actions_total');
        // Your logic...
    }
}

Monitoring & Grafana

Prometheus Configuration

scrape_configs:
  - job_name: 'laravel_api'
    scrape_interval: 15s
    metrics_path: '/metrics'
    static_configs:
      - targets: ['your-api-host:80']

Example Grafana Queries

Request Rate:

sum by(endpoint) (rate(api_requests_total[5m]))

95th Percentile Response Time:

histogram_quantile(0.95, sum(rate(api_request_duration_seconds_bucket[5m])) by (le, endpoint))

Error Rate:

sum by(endpoint) (rate(api_requests_total{status=~"5.."}[5m])) / sum by(endpoint) (rate(api_requests_total[5m])) * 100

Unique Users (per endpoint per day):

sum by(endpoint, date) (unique_users_total)

Management

Flush Metrics

# Reset all metrics data
php artisan api-metrics:flush

# Flush specific driver
php artisan api-metrics:flush --driver=redis

Or programmatically:

use SidcorpResource\ApiMetricsExporter\Facades\Metrics;

$success = Metrics::flushMetrics();

Troubleshooting

If you encounter errors related to Redis (e.g., Class "Redis" not found), ensure the PHP Redis extension is installed:

# Ubuntu/Debian
sudo apt-get install php-redis

# CentOS/RHEL
sudo yum install php-redis

# macOS with Homebrew
brew install php-redis
pecl install redis

Then restart your web server and verify the extension is loaded with:

php -m | grep redis

Environment Check

Create a simple compatibility check:

<?php
echo "PHP Version: " . PHP_VERSION . " (>= 8.1.0 required)\n";
echo "Redis: " . (extension_loaded('redis') ? "✓" : "✗ REQUIRED") . "\n";

FAQ

Does this affect performance?
Minimal impact. The middleware is lightweight and fails gracefully.

What about high-traffic APIs?
Redis driver handles high traffic and supports horizontal scaling.

How to exclude routes?
Set excluded_paths: ['health', 'debug*'] in config (supports wildcards).

Is phpredis extension required?
Yes, as of version 2.0, the phpredis extension is required for the Redis driver.

Metric Naming Conventions

This library strictly follows Prometheus metric naming conventions to ensure compatibility with monitoring tools. See details in Metrics Conventions Documentation.

Testing

composer install
composer test

Documentation

Detailed documentation can be found in the .docs directory:

• Metrics Conventions - Naming conventions and standards
• Grafana Integration - Setting up Grafana dashboards
• Project Instructions - Development guidelines

Contributing

Contributions are welcome! Please see CONTRIBUTING.md for guidelines.

License

The MIT License (MIT). See License File for more information.

Versioning

From version v1.0.0, this project strictly follows Semantic Versioning (semver): v1.0.0, v1.0.1, v1.1.0, v2.0.0, ...

This library is developed and maintained by SidCorp IT Department.