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#!perl
# Note: This script is a CLI for Riap function /App/AlgorithmBackoffUtils/retry_mimd
# and generated automatically using Perinci::CmdLine::Gen version 0.497
our $AUTHORITY = 'cpan:PERLANCAR'; # AUTHORITY
our $DATE = '2020-10-20'; # DATE
our $DIST = 'App-AlgorithmBackoffUtils'; # DIST
our $VERSION = '0.005'; # VERSION
use 5.010001;
use strict;
use warnings;
use Log::ger;
use Perinci::CmdLine::Any;
my $cmdline = Perinci::CmdLine::Any->new(
    url => "/App/AlgorithmBackoffUtils/retry_mimd",
    program_name => "retry-mimd",
    log => 1,
    log_level => "info",
    read_config => 0,
    read_env => 0,
);
$cmdline->run;
# ABSTRACT: Retry a command with MIMD (multiplicative increase, multiplicative decrease) backoff
# PODNAME: retry-mimd
__END__
HideShow 311 lines of Pod
=pod
=encoding UTF-8
=head1 NAME
retry-mimd - Retry a command with MIMD (multiplicative increase, multiplicative decrease) backoff
=head1 VERSION
This document describes version 0.005 of retry-mimd (from Perl distribution App-AlgorithmBackoffUtils), released on 2020-10-20.
=head1 SYNOPSIS
Usage:
 % retry-mimd [-D] [--consider-actual-delay] [--debug]
     [--delay-multiple-on-failure=s] [--delay-multiple-on-success=s]
     [--dry-run] [--format=name] [--initial-delay=s] [--jitter-factor=s]
     [--json] [--log-level=level] [--max-actual-duration=s]
     [--max-attempts=s] [--max-delay=s] [--min-delay=s] [--(no)naked-res]
     [--no-consider-actual-delay] [--noconsider-actual-delay]
     [--page-result[=program]] [--quiet] [--retry-on=s] [--skip-delay]
     [--success-on=s] [--trace] [--verbose] <command> ...
=head1 OPTIONS
C<*> marks required options.
=head2 Main options
=over
=item B<--command-json>=I<s>
See C<--command>.
=item B<--command>=I<s@>*
Can be specified multiple times.
=item B<--delay-multiple-on-failure>=I<s>*
How much to multiple previous delay, upon failure (e.g. 1.5).
=item B<--delay-multiple-on-success>=I<s>*
How much to multiple previous delay, upon success (e.g. 0.5).
=item B<--initial-delay>=I<s>*
Initial delay for the first attempt after failure, in seconds.
=item B<--retry-on>=I<s>
Comma-separated list of exit codes that should trigger retry.
By default, all non-zero exit codes will trigger retry.
=item B<--skip-delay>, B<-D>
Do not delay at all.
Useful for testing, along with --dry-run, when you just want to see how the
retries are done (the number of retries, along with the number of seconds of
delays) by seeing the log messages, without actually delaying.
=item B<--success-on>=I<s>
Comma-separated list of exit codes that mean success.
By default, only exit code 0 means success.
=back
=head2 Common to all algorithms options
=over
=item B<--consider-actual-delay>
Whether to consider actual delay.
If set to true, will take into account the actual delay (timestamp difference).
For example, when using the Constant strategy of delay=2, you log failure()
again right after the previous failure() (i.e. specify the same timestamp).
failure() will then return ~2+2 = 4 seconds. On the other hand, if you waited 2
seconds before calling failure() again (i.e. specify the timestamp that is 2
seconds larger than the previous timestamp), failure() will return 2 seconds.
And if you waited 4 seconds or more, failure() will return 0.
=item B<--jitter-factor>=I<s>
How much to add randomness.
If you set this to a value larger than 0, the actual delay will be between a
random number between original_delay * (1-jitter_factor) and original_delay *
(1+jitter_factor). Jitters are usually added to avoid so-called "thundering
herd" problem.
The jitter will be applied to delay on failure as well as on success.
=item B<--max-actual-duration>=I<s>
Maximum number of seconds for all of the attempts (0 means unlimited).
Default value:
 0
If set to a positive number, will limit the number of seconds for all of the
attempts. This setting is used to limit the amount of time you are willing to
spend on a task. For example, when using the Exponential strategy of
initial_delay=3 and max_attempts=10, the delays will be 3, 6, 12, 24, ... If
failures are logged according to the suggested delays, and max_actual_duration
is set to 21 seconds, then the third failure() will return -1 instead of 24
because 3+6+12 >= 21, even though max_attempts has not been exceeded.
=item B<--max-attempts>=I<s>
Maximum number consecutive failures before giving up.
Default value:
 0
0 means to retry endlessly without ever giving up. 1 means to give up after a
single failure (i.e. no retry attempts). 2 means to retry once after a failure.
Note that after a success, the number of attempts is reset (as expected). So if
max_attempts is 3, and if you fail twice then succeed, then on the next failure
the algorithm will retry again for a maximum of 3 times.
=item B<--max-delay>=I<s>
Maximum delay time, in seconds.
=item B<--min-delay>=I<s>
Maximum delay time, in seconds.
Default value:
 0
=back
=head2 Logging options
=over
=item B<--debug>
Shortcut for --log-level=debug.
=item B<--log-level>=I<s>
Set log level.
=item B<--quiet>
Shortcut for --log-level=error.
=item B<--trace>
Shortcut for --log-level=trace.
=item B<--verbose>
Shortcut for --log-level=info.
=back
=head2 Output options
=over
=item B<--format>=I<s>
Choose output format, e.g. json, text.
Default value:
 undef
=item B<--json>
Set output format to json.
=item B<--naked-res>
When outputing as JSON, strip result envelope.
Default value:
 0
By default, when outputing as JSON, the full enveloped result is returned, e.g.:
    [200,"OK",[1,2,3],{"func.extra"=>4}]
The reason is so you can get the status (1st element), status message (2nd
element) as well as result metadata/extra result (4th element) instead of just
the result (3rd element). However, sometimes you want just the result, e.g. when
you want to pipe the result for more post-processing. In this case you can use
`--naked-res` so you just get:
    [1,2,3]
=item B<--page-result>
Filter output through a pager.
=back
=head2 Other options
=over
=item B<--dry-run>
Run in simulation mode (also via DRY_RUN=1).
Default value:
 ""
=item B<--help>, B<-h>, B<-?>
Display help message and exit.
=item B<--version>, B<-v>
Display program's version and exit.
=back
=head1 COMPLETION
This script has shell tab completion capability with support for several
shells.
=head2 bash
To activate bash completion for this script, put:
 complete -C retry-mimd retry-mimd
in your bash startup (e.g. F<~/.bashrc>). Your next shell session will then
recognize tab completion for the command. Or, you can also directly execute the
line above in your shell to activate immediately.
It is recommended, however, that you install modules using L<cpanm-shcompgen>
which can activate shell completion for scripts immediately.
=head2 tcsh
To activate tcsh completion for this script, put:
 complete retry-mimd 'p/*/`retry-mimd`/'
in your tcsh startup (e.g. F<~/.tcshrc>). Your next shell session will then
recognize tab completion for the command. Or, you can also directly execute the
line above in your shell to activate immediately.
It is also recommended to install L<shcompgen> (see above).
=head2 other shells
For fish and zsh, install L<shcompgen> as described above.
=head1 HOMEPAGE
Please visit the project's homepage at L<https://metacpan.org/release/App-AlgorithmBackoffUtils>.
=head1 SOURCE
Source repository is at L<https://github.com/perlancar/perl-App-AlgorithmBackoffUtils>.
=head1 BUGS
Please report any bugs or feature requests on the bugtracker website L<https://rt.cpan.org/Public/Dist/Display.html?Name=App-AlgorithmBackoffUtils>
When submitting a bug or request, please include a test-file or a
patch to an existing test-file that illustrates the bug or desired
feature.
=head1 SEE ALSO
L<Algorithm::Backoff::MIMD>.
=head1 AUTHOR
perlancar <perlancar@cpan.org>
=head1 COPYRIGHT AND LICENSE
This software is copyright (c) 2020, 2019 by perlancar@cpan.org.
This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.
=cut