OpenTelemetry for Perl

This is part of an ongoing attempt at implementing the OpenTelemetry standard in Perl. The distribution in this repository implements the abstract OpenTelemetry API, with an SDK implementation being worked on separately.

What is OpenTelemetry?

OpenTelemetry is an open source observability framework, providing a general-purpose API, SDK, and related tools required for the instrumentation of cloud-native software, frameworks, and libraries.

OpenTelemetry provides a single set of APIs, libraries, agents, and collector services to capture distributed traces and metrics from your application. You can analyze them using Prometheus, Jaeger, and other observability tools.

How does this distribution fit in?

This distribution defines the core OpenTelemetry interfaces in the form of abstract classes and no-op implementations. That is, it defines interfaces and data types sufficient for a library or application to code against to produce telemetry data, but does not actually collect, analyze, or export the data.

To collect and analyze telemetry data, applications should also install a concrete implementation of the API. None exists at the moment, but work on this should start next.

This separation allows libraries that produce telemetry data to depend only on the API, deferring the choice of concrete implementation to the application developer.

How do I get started?

Install this distribution from the repository (the aim is for it to be on CPAN at some point):

cd path/to/this/repo
cpanm install .

Then, use the OpenTelemetry interfaces to produces traces and other telemetry data. Following is a basic example (although bear in mind this interface is still being drafted, so some details might change):

use OpenTelemetry;
use v5.36;

# Obtain the current default tracer provider
my $provider = OpenTelemetry->tracer_provider;

# Create a trace
my $tracer = $provider->tracer( name => 'my_app', version => '1.0' );

# Record spans
$tracer->in_span( outer => sub ( $span, $context ) {
    # In outer span

    $tracer->in_span( inner => sub ( $span, $context ) {
        # In inner span
    });
});