AWS::XRay - AWS X-Ray tracing library


    use AWS::XRay qw/ capture /;

    capture "myApp", sub {
        capture "remote", sub {
            # do something ...
            capture "nested", sub {
                # ...
        capture "myHTTP", sub {
            my $segment = shift;
            # ...
            $segment->{http} = { # modify segment document
                request => {
                    method => "GET",
                    url    => "http://localhost/",
                response => {
                    status => 200,

    my $header;
    capture "source", sub {
        my $segment = shift;
        $header = $segment->trace_header;
    capture_from $header, "dest", sub {
        my $segment = shift;  # is a child of "source" segment
        # ...


AWS::XRay is a tracing library with AWS X-Ray.

AWS::XRay sends segment data to AWS X-Ray Daemon.



Generate a Trace ID. (e.g. "1-581cf771-a006649127e371903a2de979")


capture($name, $code)

capture() executes $code->($segment) and send the segment document to X-Ray daemon.

$segment is a AWS::XRay::Segment object.

When $AWS::XRay::TRACE_ID is not set, generates TRACE_ID automatically.

When capture() called from other capture(), $segment is a sub segment document.

See also AWS X-Ray Segment Documents.

capture_from($header, $name, $code)

capture_from() parses the trace header and capture the $code with sub segment of header's segment.


    my ($trace_id, $segment_id) = parse_trace_header($header);

Parse a trace header (e.g. "Root=1-5759e988-bd862e3fe1be46a994272793;Parent=53995c3f42cd8ad8").

add_capture($package, $method1[, $method2, ...])

add_capture() adds a capture to package::method.

    AWS::XRay->add_capture("MyApp::Model", "foo", "bar");

The segments of these captures are named as "MyApp::Model". These segments include metadata "method": "foo" or "bar".



Set/Get a sampling rate for capture().

    AWS::XRay->sampling_rate(0.1); # 10% sampling

$rate is allowed a float value between 0 and 1.

0 means disable tracing. 1 means all of capture() are traced.

When capture_from() called with a trace header includes "Sampled=1", all of followed capture() are traced.


Set/Get a code ref to sample for capture().

    AWS::XRay->sampler(sub {
        if ($some_condition) {
           return 1;
        } else {
           return 0;


Set/Get auto flush mode.

When $mode is 1 (default), segment data will be sent to xray daemon immediately after capture() called.

When $mode is 0, segment data are buffered in memory. You should call AWS::XRay->sock->flush() to send the buffered segment data or call AWS::XRay->sock->close() to discard the buffer.

AWS_XRAY_DAEMON_ADDRESS environment variable

Set the host and port of the X-Ray daemon. Default


Copyright (C) FUJIWARA Shunichiro.

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


FUJIWARA Shunichiro <>