govproc-pericmd - Perinci::CmdLine-based variant of govproc CLI
This document describes version 0.001 of govproc-pericmd (from Perl distribution App-govproc-pericmd), released on 2019-05-22.
Use as you would use govproc:
% govproc-pericmd --euid tono --timeout '2.5 hours' ...
This script is just like govproc but uses the Perinci::CmdLine CLI framework to give you conveniences like shell tab completion and argument coercions (see the above example in Synopsis).
* marks required options.
*
Command to run (JSON-encoded).
See --command.
--command
Command to run.
Passed to <pm:IPC::Run>'s `start()`.
Can be specified multiple times.
Instead of kill, use killfam (kill family of process).
This can be useful e.g. to control load more successfully, if the load-generating processes are the subchildren of the one we're governing.
This requires <pm:Proc::Killfam> CPAN module, which is installed separately.
Should match regex `\A\w+\z`. Used in several places, e.g. passed as `prefix` in <pm:File::Write::Rotate>'s constructor as well as used as name of PID file.
If not given, will be taken from command.
Directory to put PID file in.
Set path to configuration file.
Set configuration profile to use.
Do not use any configuration file.
Do not read environment for default options.
Valid values:
["exit"]
Can be set to `exit` to silently exit when there is already a running instance. Otherwise, will print an error message `Program <NAME> already running`.
If set to true, will prevent running multiple instances simultaneously. Implemented using <pm:Proc::PID::File>. You will also normally have to set `pid_dir`, unless your script runs as root, in which case you can use the default `/var/run`.
Frequency of load checking.
Default value:
10
See --load-high-limit.
--load-high-limit
Limit above which program should be suspended, if load watching is enabled. If integer, will be compared against <pm:Unix::Uptime>`->load`'s `$load1` value. Alternatively, you can provide a custom routine here, code should return true if load is considered too high.
Note: `load_watch` needs to be set to true first for this to be effective.
See --load-low-limit.
--load-low-limit
Limit below which program should resume, if load watching is enabled. If integer, will be compared against <pm:Unix::Uptime>`->load`'s `$load1` value. Alternatively, you can provide a custom routine here, code should return true if load is considered low.
If set to 1, enable load watching. Program will be suspended when system load is too high and resumed if system load returns to a lower limit.
Shortcut for --log-level=debug.
Set log level.
Will be passed as arguments to `File::Write::Rotate` (JSON-encoded).
See --log-stderr.
--log-stderr
Will be passed as arguments to `File::Write::Rotate`.
Specify logging for STDERR. Logging will be done using <pm:File::Write::Rotate>. Known hash keys: `dir` (STR, defaults to `/var/log`, directory, preferably absolute, where the log file(s) will reside, should already exist and be writable, will be passed to <pm:File::Write::Rotate>'s constructor), `size` (int, also passed to <pm:File::Write::Rotate>'s constructor), `histories` (int, also passed to <pm:File::Write::Rotate>'s constructor), `period` (str, also passed to <pm:File::Write::Rotate>'s constructor).
See --log-stdout.
--log-stdout
Shortcut for --log-level=error.
Shortcut for --log-level=trace.
Shortcut for --log-level=info.
Can be used to turn off STDERR output. If you turn this off and set `log_stderr`, STDERR output will still be logged but not displayed to screen.
Choose output format, e.g. json, text.
undef
Set output format to json.
When outputing as JSON, strip result envelope.
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]
If set to true, do restart.
Prevent screensaver from being activated.
Set EGID(s) of command process.
Need to be root to be able to setuid.
Set EUID of command process.
Apply execution time limit, in seconds.
After this time is reached, process (and all its descendants) are first sent the TERM signal. If after 30 seconds pass some processes still survive, they are sent the KILL signal.
The killing is implemented using <pm:IPC::Run>'s `kill_kill()`.
Upon timeout, exit code is set to 124.
Display help message and exit.
Display program's version and exit.
This script has shell tab completion capability with support for several shells.
To activate bash completion for this script, put:
complete -C govproc-pericmd govproc-pericmd
in your bash startup (e.g. ~/.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 cpanm-shcompgen which can activate shell completion for scripts immediately.
To activate tcsh completion for this script, put:
complete govproc-pericmd 'p/*/`govproc-pericmd`/'
in your tcsh startup (e.g. ~/.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 shcompgen (see above).
For fish and zsh, install shcompgen as described above.
This script can read configuration files. Configuration files are in the format of IOD, which is basically INI with some extra features.
By default, these names are searched for configuration filenames (can be changed using --config-path): ~/.config/govproc-pericmd.conf, ~/govproc-pericmd.conf, or /etc/govproc-pericmd.conf.
--config-path
All found files will be read and merged.
To disable searching for configuration files, pass --no-config.
--no-config
You can put multiple profiles in a single file by using section names like [profile=SOMENAME] or [SOMESECTION profile=SOMENAME]. Those sections will only be read if you specify the matching --config-profile SOMENAME.
[profile=SOMENAME]
[SOMESECTION profile=SOMENAME]
--config-profile SOMENAME
You can also put configuration for multiple programs inside a single file, and use filter program=NAME in section names, e.g. [program=NAME ...] or [SOMESECTION program=NAME]. The section will then only be used when the reading program matches.
program=NAME
[program=NAME ...]
[SOMESECTION program=NAME]
Finally, you can filter a section by environment variable using the filter env=CONDITION in section names. For example if you only want a section to be read if a certain environment variable is true: [env=SOMEVAR ...] or [SOMESECTION env=SOMEVAR ...]. If you only want a section to be read when the value of an environment variable has value equals something: [env=HOSTNAME=blink ...] or [SOMESECTION env=HOSTNAME=blink ...]. If you only want a section to be read when the value of an environment variable does not equal something: [env=HOSTNAME!=blink ...] or [SOMESECTION env=HOSTNAME!=blink ...]. If you only want a section to be read when an environment variable contains something: [env=HOSTNAME*=server ...] or [SOMESECTION env=HOSTNAME*=server ...]. Note that currently due to simplistic parsing, there must not be any whitespace in the value being compared because it marks the beginning of a new section filter or section name.
env=CONDITION
[env=SOMEVAR ...]
[SOMESECTION env=SOMEVAR ...]
[env=HOSTNAME=blink ...]
[SOMESECTION env=HOSTNAME=blink ...]
[env=HOSTNAME!=blink ...]
[SOMESECTION env=HOSTNAME!=blink ...]
[env=HOSTNAME*=server ...]
[SOMESECTION env=HOSTNAME*=server ...]
List of available configuration parameters:
command (see --command) egid (see --egid) euid (see --euid) format (see --format) killfam (see --killfam) load_check_every (see --load-check-every) load_high_limit (see --load-high-limit) load_low_limit (see --load-low-limit) load_watch (see --load-watch) log_level (see --log-level) log_stderr (see --log-stderr) log_stdout (see --log-stdout) naked_res (see --naked-res) name (see --name) no_screensaver (see --no-screensaver) on_multiple_instance (see --on-multiple-instance) pid_dir (see --pid-dir) restart (see --restart) show_stderr (see --no-show-stderr) show_stdout (see --no-show-stdout) single_instance (see --single-instance) timeout (see --timeout)
Specify additional command-line options.
~/.config/govproc-pericmd.conf
~/govproc-pericmd.conf
/etc/govproc-pericmd.conf
Please visit the project's homepage at https://metacpan.org/release/App-govproc-pericmd.
Source repository is at https://github.com/perlancar/perl-App-govproc-pericmd.
Please report any bugs or feature requests on the bugtracker website https://rt.cpan.org/Public/Dist/Display.html?Name=App-govproc-pericmd
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.
govproc
perlancar <perlancar@cpan.org>
This software is copyright (c) 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.
To install App::govproc::pericmd, copy and paste the appropriate command in to your terminal.
cpanm
cpanm App::govproc::pericmd
CPAN shell
perl -MCPAN -e shell install App::govproc::pericmd
For more information on module installation, please visit the detailed CPAN module installation guide.