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NAME

OpenTelemetry::Integration - Top-level interface for OpenTelemetry integrations

SYNOPSIS

    # Load integrations for specific modules
    use OpenTelemetry::Integration qw( HTTP::Tiny DBI );

    # Some integrations can take additional options
    use OpenTelemetry::Integration 'HTTP::Tiny' => \%options;

    # Load every available integration
    use OpenTelemetry::Integration -all;

DESCRIPTION

This is the base class for handling tracing integration with other CPAN modules.

It provides functionality for loading available integrations via the import list on a use statement:

  • with -all, all available OpenTelemetry integrations will be loaded, if the module the integration is for has already been loaded

  • with a specific list of modules, they will be loaded (even if they haven't been before) and integrations for them will be applied if available

This means that you can expect HTTP::Tiny to be traced if you have the OpenTelemetry::Integration::HTTP::Tiny module installed and you do this:

    use OpenTelemetry::Integration 'HTTP::Tiny';

or this:

    use HTTP::Tiny;
    use OpenTelemetry::Integration -all;

but it will not be traced if you do this:

    use OpenTelemetry::Integration -all;
    use HTTP::Tiny;

The rationale behind this apparently inconsistent behaviour is that, with a large install, :all might load unexpected integrations. This behaviour allows you instead to add this line after your module imports, and any functionality that is actively being used in the code (for which an integration module is available) would gain tracing.

Configuring integrations

WRITING INTEGRATIONS

Additional integrations can be written and used as long as they are in the the OpenTelemetry::Integration namespace. They should subclass this module (OpenTelemetry::Integration) and should implement an install class method as described in detail below. Other methods described in this section are optional, but can be used to provide additional features.

install

    $bool = $class->install(%configuration);

Installs the integration. Will be called with a (possibly empty) list of key/value pairs with configuration options, and is expected to return a true value if the integration was installed, or false otherwise.

An example implementation of this method might look like the following:

    package OpenTelemetry::Integration::Foo::Bar;

    use experimental 'signatures';
    use Class::Inspector;
    use Class::Method::Modifiers 'install_modifier';

    my $loaded;
    sub install ( $class, %config ) {
        return if $loaded++;
        return unless Class::Inspector->loaded('Foo::Bar');

        install_modifier 'Foo::Bar' => around => reticulate_splines => sub {
            my ( $orig, $self, @args ) = @_;
            ...
            my $value = $self->$orig(@args);
            ...
            return $value;
        };

        return 1;
    }

dependencies

    @package_names = $class->dependencies;

Should return the names of the packages that should be loaded to install this integration. This method will be called in list context when loading dependencies automatically (ie. not when using the all flag) to load the dependencies before calling "install".

COPYRIGHT

This software is copyright (c) 2023 by José Joaquín Atria.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.