NAME

    Net::Prometheus - export monitoring metrics for prometheus

SYNOPSIS

       use Net::Prometheus;
    
       my $client = Net::Prometheus->new;
    
       my $counter = $client->new_counter(
          name => "requests",
          help => "Number of received requests",
       );
    
       sub handle_request
       {
          $counter->inc;
          ...
       }
    
       use Plack::Builder;
    
       builder {
          mount "/metrics" => $client->psgi_app;
          ...
       }

DESCRIPTION

    This module provides the ability for a program to collect monitoring
    metrics and export them to the prometheus.io monitoring server.

    As prometheus will expect to collect the metrics by making an HTTP
    request, facilities are provided to yield a PSGI application that the
    containing program can embed in its own structure to provide the
    results, or the application can generate a plain-text result directly
    and serve them by its own means.

CONSTRUCTOR

 new

       $prometheus = Net::Prometheus->new;

    Returns a new Net::Prometheus instance.

METHODS

 register

 unregister

 new_gauge

       $gauge = $prometheus->new_gauge( %args )

    Constructs a new Net::Prometheus::Gauge using the arguments given and
    registers it with the exporter. The newly-constructed gauge is
    returned.

 new_counter

       $counter = $prometheus->new_counter( %args )

    Constructs a new Net::Prometheus::Counter using the arguments given and
    registers it with the exporter. The newly-constructed counter is
    returned.

 new_summary

       $summary = $prometheus->new_summary( %args )

    Constructs a new Net::Prometheus::Summary using the arguments given and
    registers it with the exporter. The newly-constructed summary is
    returned.

 render

       $str = $prometheus->render

    Returns a string in the Prometheus text exposition format containing
    the current values of all the registered metrics.

 psgi_app

       $app = $prometheus->psgi_app

    Returns a new PSGI application as a CODE reference. This application
    will render the metrics in the Prometheus text exposition format,
    suitable for scraping by the Prometheus collector.

    This application will respond to any GET request, and reject requests
    for any other method.

TODO

      * Document the Collector / Metric distinction. Document how to make
      custom Collectors

      * Process collector.

      * Callback gauges.

      * Split Registry out from toplevel instance.

      * Write some actual example programs.

AUTHOR

    Paul Evans <leonerd@leonerd.org.uk>