Using counter type metric | laravel-prometheus | Spatie

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=====================

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  [Docs](https://spatie.be/docs)  [Laravel-prometheus](https://spatie.be/docs/laravel-prometheus/v1)  Advance-usage  Using counter type metric

 Version   v1

 Other versions for crawler [v1](https://spatie.be/docs/laravel-prometheus/v1)

- [ Introduction ](https://spatie.be/docs/laravel-prometheus/v1/introduction)
- [ Support us ](https://spatie.be/docs/laravel-prometheus/v1/support-us)
- [ Requirements ](https://spatie.be/docs/laravel-prometheus/v1/requirements)
- [ Installation & setup ](https://spatie.be/docs/laravel-prometheus/v1/installation-setup)
- [ Questions and issues ](https://spatie.be/docs/laravel-prometheus/v1/questions-issues)
- [ Changelog ](https://spatie.be/docs/laravel-prometheus/v1/changelog)
- [ About us ](https://spatie.be/docs/laravel-prometheus/v1/about-us)

Basic usage
-----------

- [ Creating gauges ](https://spatie.be/docs/laravel-prometheus/v1/basic-usage/creating-gauges)
- [ Using Horizon exporters ](https://spatie.be/docs/laravel-prometheus/v1/basic-usage/using-horizon-exporters)
- [ Using Queue exporters ](https://spatie.be/docs/laravel-prometheus/v1/basic-usage/using-queue-exporters)

Setting up Prometheus and Grafana
---------------------------------

- [ Introduction ](https://spatie.be/docs/laravel-prometheus/v1/setting-up-prometheus-and-grafana/introduction)
- [ Using grafana.com ](https://spatie.be/docs/laravel-prometheus/v1/setting-up-prometheus-and-grafana/using-grafana-com)
- [ Self-hosted ](https://spatie.be/docs/laravel-prometheus/v1/setting-up-prometheus-and-grafana/self-hosted)
- [ Using fly.io ](https://spatie.be/docs/laravel-prometheus/v1/setting-up-prometheus-and-grafana/using-fly-metrics)

Advanced usage
--------------

- [ Creating multiple endpoints ](https://spatie.be/docs/laravel-prometheus/v1/advance-usage/using-multiple-endpoints)
- [ Creating collectors ](https://spatie.be/docs/laravel-prometheus/v1/advance-usage/creating-collectors)
- [ Using counter type metric ](https://spatie.be/docs/laravel-prometheus/v1/advance-usage/using-counter-metric)

 Using counter type metric
=========================

###  On this page

1. [ Using Counter Type Metric ](#content-using-counter-type-metric)
2. [ Cache Configuration ](#content-cache-configuration)

Using Counter Type Metric
-----------------------------------------------------------------------------------------------------------------------------------

**Overview**

A Counter is a metric that only increases in value. It is typically used to count events, such as the number of requests received or tasks completed.

**Creating a Counter**

You can create a Counter metric using the `addCounter` method:

```
$counter = Prometheus::addCounter('my_counter');
```

**Setting an Initial Value**

You can also define an initial value for your counter when creating it. This is useful if you want to start counting from a specific number:

```
$counter = Prometheus::addCounter('my counter')->setInitialValue(100);
```

**Incrementing the Counter**

To increment the counter, you can use the `inc` method:

```
$counter->inc();
```

This will increase the counter by one.

If you need to increment the counter by a value greater than one, you can pass the value as an argument to the `inc()` method:

```
$counter->inc(2);
```

**Best Practices**

- **Naming Conventions:** Use descriptive names for your counters to make it clear what they are tracking. For example, `user_registration_total` or `api_request_count`.
- **Atomic Increments:** Ensure that increments are atomic, especially in multi-threaded or multi-process environments, to avoid race conditions.

Cache Configuration
-----------------------------------------------------------------------------------------------------------------

By default, the cache setting is set to `null`, which means that the metric will be stored in memory without using Laravel's caching system. This is suitable for simple setups or testing environments.

### Configuring Cache

You can configure the cache in the config/prometheus.php file:

```
/**
* Select a cache to store gauges, counters, summaries and histograms between requests.
* In a multi node setup you should ensure that each node writes to its own
* cache instance or uses a node specific prefix.
* Configure the cache store in config/cache.php.
*
* to use an in memory adapter for testing use array or null as your store
* or remove the cache entry all together:
*  'cache' => null       // InMemory implementation without laravel cache
*  'cache' => 'array'    // InMemory implementation using laravel cache
*/
'cache' => null,
```

### Cache Options

- **In-Memory Cache:** If you want to use an in-memory cache without relying on Laravel's cache system, keep the cache option as null.
- **Laravel Cache:** To store metrics in Laravel's cache, set the cache option to a valid cache driver defined in your `config/cache.php` file: ```
    'cache' => 'redis', // Using Redis for caching metrics
    ```

### Conclusion

By properly configuring the cache, you can ensure that your metrics are persisted and shared across requests, making them more reliable in production environments.