NAME
OpenTelemetry::Trace::Span::Processor - Abstract interface of an OpenTelemetry span processor
SYNOPSIS
use Object::Pad;
use Future::AsyncAwait;
class My::Processor :does(OpenTelemetry::Trace::Span::Processor) {
method on_start ( $span, $context ) { ... }
method on_end ( $span ) { ... }
async method shutdown ( $timeout // undef ) { ... }
async method force_flush ( $timeout // undef ) { ... }
}
# Create it
my $processor = My::Processor->new( ... );
# Register it with the OpenTelemetry tracer provider
OpenTelemetry->tracer_provider->add_span_processor($processor);DESCRIPTION
This module provides an abstract role that can be used by classes implementing OpenTelemetry span processors. Span processors are objects that are registered with a OpenTelemetry::Trace::TracerProvider (or, more accurately, with one of its subclasses such as those provided by an OpenTelemetry SDK) to perform additional operations on spans when they start and end.
The processor is considered to be the start of a pipeline, which must be allowed to end with a OpenTelemetry::Exporter to export the telemetry data to some collector. To this end, processors are expected to accept an optional exporter parameter to their constructor. But processors can be used for other ends.
METHODS
new
$processor = Class::Implementing::This::Role->new(
exporter => ..., # optional
...
);Should take an optional exporter set to an instance of a class implementing the OpenTelemetry::Exporter role. Processor classes are free to accept any other parameters they choose.
on_start
$processor->on_start( $span, $parent_context );Called when the span is started. It takes the newly created span object, and the OpenTelemetry::Context that holds the span's parent span, if any. This is the same value that was passed as the parent paremeter to "create_span" in OpenTelemetry::Trace::Tracer.
If the span that was created was a root span (a span without a parent), this value may be undefined, or it may be a OpenTelemetry::Context that does not hold a span.
This method is called synchronously when the span was created, so it should not block or die.
The return value of this method is ignored.
on_end
$processor->on_end( $span );Called as soon as possible after the span has ended (so the end timestamp is already known). It takes the span that has just ended as its only parameter.
This method is called synchronously when the span was created, so it should not block or die.
The return value of this method is ignored.
shutdown
$result = await $processor->shutdown( $timeout // undef );Takes an optional timeout value and returns a Future that will be done when this span processor has completed shutting down. The shutdown process must include the effects of force_flush, described below. After shutting down, the processor is not expected to do any further work, and should ignore any subsequent calls.
The value of the future will be one of the "Trace export results" in OpenTelemetry::Constants.
force_flush
$result = await $processor->force_flush( $timeout // undef );Takes an optional timeout value and returns a Future that will be done when this span processor has finished flushing. Flushing signals to the span processor that it should process the data for any unprocessed spans as soon as possible. This could be due to an imminent shutdown, but does not have to be.
The value of the future will be one of the "Trace export results" in OpenTelemetry::Constants.
SEE ALSO
- Future
- OpenTelemetry::Constants
- OpenTelemetry::Exporter
- OpenTelemetry::Trace::TracerProvider
- OpenTelemetry::SDK
- OpenTelemetry::SDK::Trace::Span::Readable
COPYRIGHT AND LICENSE
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.