NAME

OpenTracing::GlobalTracer - Easy Access to the Tracer Singleton

SYNOPSIS

    use OpenTracing::GlobalTracer qw/$TRACER/;
    
    my $foo_tracer = OpenTracing::Implementation::Foo::Tracer->new( );
    OpenTracing::GlobalTracer->set_global_trace( $foo_tracer );

and in the various part of the code:

    my $global_tracer = OpenTracing::GlobalTracer->get_global_tracer( );
    my $span  = $global_tracer->get_active_span;

    my $scope = $TRACER->start_active_span( $operation_name );

DESCRIPTION

This module give easy access to the OpenTracing singleton.

During import, when `use`ing the module, it can take the name of a variable to use in the current scope.

The modules provide two methods, `set_global_tracer` and `get_global_tracer`.

If none is set (or cleared), per definition, it will give back a 'NoOp' implementation.

CLASS METHODS

set_global_tracer

    OpenTracing::GlobalTracer->set_global_trace( $tracer );

Sets the global tracer singleton.

get_global_tracer

    my $global_tracer = OpenTracing::GlobalTracer->get_global_tracer( );

Returns a global tracer if some is set. If none is set, it will return the OpenTracing::Implementation::NoOp implementation, compliant to the definition to prevent crashing.

ENVIRONMENT VARIABLES

OPENTRACING_GLOBALTRACER_DEFAULT

This variable can be set to override the default NoOp implementation.

CAVEATS

When using the $TRACER variable, one still needs to be careful, it could be undef if no tracer wasn't initialised, or explicitly been erased. This may result in errors like "can't use method ... on undef".

AUTHOR

Theo van Hoesel <tvanhoesel@perceptyx.com>

COPYRIGHT AND LICENSE

'OpenTracing GlobalTracer' is Copyright (C) 2019, Perceptyx Inc

This package is free software; you can redistribute it and/or modify it under the terms of the Artistic License 2.0.

This package is distributed in the hope that it will be useful, but it is provided "as is" and without any express or implied warranties.

For details, see the full text of the license in the file LICENSE.