Ecosyste.ms: Awesome

An open API service indexing awesome lists of open source software.

Awesome Lists | Featured Topics | Projects

https://github.com/lancew/scientist

Perl 5 Scientist - Test new code against old
https://github.com/lancew/scientist

Last synced: 23 days ago
JSON representation

Perl 5 Scientist - Test new code against old

Awesome Lists containing this project

README 

        

=encoding UTF-8



=head1 NAME



Scientist - Test new code against old.



=for HTML










=head1 DESCRIPTION



Perl module inspired by https://github.com/github/scientist ( http://githubengineering.com/scientist/ )



=head1 SYNOPSIS



  use feature qw(say);

  use Scientist;



  sub old_code {

    return 10;

  }



  sub new_code {

    return 20;

  }



  my $experiment = Scientist->new(

    experiment => 'MyTest',

    use => \&old_code,

    try => \&new_code,

  );



  my $answer = $experiment->run;



  say "The number ten is $answer";

  warn 'There was a mismatch between control and candidate'

    if $experiment->result->{'mismatched'};



  say 'Timings:';

  say 'Control code:   ', $experiment->result->{control}{duration}, ' microseconds';

  say 'Candidate code: ', $experiment->result->{candidate}{duration}, ' microseconds';



=head1 Introduction



This module is inspired by the Scientist ruby code released by GitHub under the MIT license in 2015/2016.



In February 2016, I started writing this Perl module to bring similar ideas to Perl.



Please get involved with this module. Contact [email protected] with ideas, suggestions; support, etc.



This code is also released under the MIT license to match the original Ruby implementation.



=head1 Methods / Attributes



=over



=item context()



Provide contextual information for the experiment; will be returned in the result set.



Should be a hashref.



=item enabled(|)



DEFAULT : TRUE



Boolean switch to enable or disable the experiment. If disabled the experiment will only return

the control code (use) result. The candidate code (try) will NOT be executed. The results set will

not be populated.



=item experiment()



DEFAULT : C's output



Simply the name of the experiment included in the result set.



=item publish



Publish is a method called by C<-Erun()>.



Scientist is designed so that you create your own personalised My::Scientist module and extend C to do what you want/need.

For example, to push timing and mismatch information to StatsD.



=item use()



Control code to be included in the experiment.



This code will be executed and returned when the experiment is run.



NB: This code is run and returned even if the experiment's C.



=item result()



Result contains the result of the experiment after it is run.



Will contain data only AFTER C<-Erun()> has been called.



Observation is included in the result, this includes matched/mismatched. If

there was a mismatch, then a diagnostic will be made available. This will

display what was expected (from the control) and what we got instead (from the

candidate).



=item run()



This method executes the control (use) code. If the experiment is C, will also run the candidate (try)

code. The control and candidate code is run in random order.



=item try()



Candidate code to be included in the experiment.



This code will be executed and discarded when the experiment is run.



=item BUILD



This creates simply creates better column headers for the diagnostic output.



=back



=head1 Functions



=over



=item name()



DEFAULT : 'experiment'



The default string name of the experiment. Intended to be optionally overriden in a subclass.



=back



=head1 Extending Publish



You can create your own Scientist module and use it to create a custom publishing methodology.



Below is a small example that pushes mismatch info and timings to StatsD:



=head2 My/Scientist.pm



  package My::Scientist;

  use parent 'Scientist';



  use Net::Statsd;



  sub publish {

    my $self = shift;



    my $experiment = $self->result->{experiment};

    # Increment counter for every match or mismatch

    Net::Statsd::increment("$experiment.mismatch") if $self->result->{mismatched};

    Net::Statsd::increment("$experiment.match") unless $self->result->{mismatched};



    # Log timings (converting Scientist microsends to StatsD miliseconds)

    # Note: This implementation rounds down the duration.

    Net::Statsd::timing("$experiment.control",   int $self->result->{control}{duration} * 1_000);

    Net::Statsd::timing("$experiment.candidate", int $self->result->{candidate}{duration} * 1_000);

  }



  1;



=head2 SomePerlScript.pl



  use strict;

  use warnings;



  use My::Scientist;



  my $experiment = My::Scientist->new(

    experiment => 'MyTest',

    use        => \&old_code,

    try        => \&new_code,

  );



  my $result = $experiment->run;



=head1 AUTHOR



Lance Wicks 



=head1 CONTRIBUTORS



James Raspass



Joshua Keroes



Mohammad S Anwar



=head1 COPYRIGHT AND LICENSE



This software is Copyright (c) 2016 by Lance Wicks.



This is free software, licensed under:



  The MIT (X11) License



The MIT License



Permission is hereby granted, free of charge, to any person

obtaining a copy of this software and associated

documentation files (the "Software"), to deal in the Software

without restriction, including without limitation the rights to

use, copy, modify, merge, publish, distribute, sublicense,

and/or sell copies of the Software, and to permit persons to

whom the Software is furnished to do so, subject to the

following conditions:



The above copyright notice and this permission notice shall

be included in all copies or substantial portions of the

Software.



THE SOFTWARE IS PROVIDED "AS IS", WITHOUT

WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,

INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF

MERCHANTABILITY, FITNESS FOR A PARTICULAR

PURPOSE AND NONINFRINGEMENT. IN NO EVENT

SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE

LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

LIABILITY, WHETHER IN AN ACTION OF CONTRACT,

TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN

CONNECTION WITH THE SOFTWARE OR THE USE OR

OTHER DEALINGS IN THE SOFTWARE.



=head1 SEE ALSO



L



L



L



L



L