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NAME

App::Cme::Command::run - Run a cme script

VERSION

version 1.040

SYNOPSIS

 $ cat ~/.cme/scripts/remove-mia
 doc: remove mia from Uploaders. Require mia parameter
 # declare app to configure
 app: dpkg
 # specify one or more instructions
 load: ! control source Uploaders:-~/$mia$/
 # commit the modifications with a message (git only)
 commit: remove MIA dev $mia

 $ cme run remove-mia -arg mia=longgone@d3bian.org

 # cme run can also use environment variables
 $ cat ~/.cme/scripts/add-me-to-uploaders
 app: dpkg-control
 load: source Uploaders:.push("$DEBFULLNAME <$DEBEMAIL>")

 $ cme run add-me-to-uploaders
 Reading package lists... Done
 Building dependency tree
 Reading state information... Done
 Changes applied to dpkg-control configuration:
 - source Uploaders:3: '<undef>' -> 'Dominique Dumont <dod@debian.org>'

 # show the script documentation
 $ cme run remove-mia -doc
 remove mia from Uploaders. require mia parameter

 # list scripts
 $ cme run -list
 Available scripts:
 - update-copyright
 - add-me-to-uploaders

DESCRIPTION

Run a script written for cme

A script passed by name is searched in ~/.cme/scripts, /etc/cme/scripts or /usr/share/perl5/Config/Model/scripts. E.g. with cme run foo, cme loads either ~/.cme/scripts/foo, /etc/cme/scripts/foo or /usr/share/perl5/Config/Model/scripts/foo

No search is done if the script is passed with a path (e.g. cme run ./foo)

cme run accepts scripts written with different syntaxes:

cme DSL

For simple script, this DSL text specifies the target app, the doc, optional variables and a load string used by Config::Model::Loader or Perl code.

YAML

Like text above, but using Yaml syntax.

Perl data structure

Writing Perl code in a text file or in a YAML field can be painful as Perl syntax is not highlighted. With a Perl data structure, a cme script specifies the target app, the doc, optional variables, and a perl subroutine (see below).

plain Perl script

cme run can also run plain Perl script. This is syntactic sugar to avoid polluting global namespace, i.e. there's no need to store a script using cme function in /usr/local/bin/. Note that the script must begin with the usual shebang line (#!) and be executable.

When run, this script:

  • opens the configuration file of app

  • applies the modifications specified with load instructions or the Perl code.

  • save the configuration files

  • commits the result if commit is specified (either in script or on command line).

See App::Cme::Command::run for details.

Syntax of text format

The script accepts instructions in the form:

 key: value

The key line can be repeated when needed.

Multi line values can also be:

 --- key
 multi line value
 ---

The script accepts the following instructions:

app

Specify the target application. Must be one of the application listed by cme list command. Mandatory. Only one app instruction is allowed.

default

Specify default values that can be used in load or var sections.

For instance:

 default: name=foobar
var

Use Perl code to specify variables usable in this script. The Perl code must store data in %var hash. For instance:

    var: my @l = localtime; $var{year} =  $l[5]+1900;

The hash %args contains the variables passed with the -arg option. Reading a value from %args which is not set by user triggers a missing option error. Use exists if you need to test if a argument was set by user:

    var: $var{foo} = exists $var{bar} ? $var{bar} : 'default' # good
    var: $var{foo} = $var{bar} || 'default' # triggers a "missing arg" error
load

Specify the modifications to apply using a string as specified in Config::Model::Loader. This string can contain variable (e.g. $foo) which are replaced by command argument (e.g. -arg foo=bar) or by a variable set in var: line (e.g. $var{foo} as set above) or by an environment variable (e.g. $ENV{foo})

code

Specify Perl code to run. See "code section" for details.

commit

Specify that the change must be committed with the passed commit message. When this option is used, cme raises an error if used on a non-clean workspace. This option works only with git.

All instructions can use variables like $stuff whose value can be specified with -arg options, with a Perl variable (from var: section explained above) or with an environment variable:

For instance:

  cme run -arg var1=foo -arg var2=bar

transforms the instruction:

  load: ! a=$var1 b=$var2

in

  load: ! a=foo b=bar

Example

Here's an example from libconfig-model-dpkg-perl scripts:

  doc: add myself to Uploaders
  app: dpkg-control
  load: source Uploaders:.insort("$DEBFULLNAME <$DEBEMAIL>")
  commit: add $DEBEMAIL to Uploaders

Code section

The code section can contain variable (e.g. $foo) which are replaced by command argument (e.g. -arg foo=bar) or by a variable set in var: line (e.g. $var{foo} as set above).

When evaluated the following variables are also set:

$root

Root node of the configuration (See Config::Model::Node)

$inst

Configuration instance (See Config::Model::Instance)

$commit_msg

Message used to commit the modification.

Since the code is run in an eval, other variables are available (like $self) to shoot yourself in the foot.

For example:

 app:  popcon
 ---code
 $root->fetch_element('MY_HOSTID')->store($to_store);
 ---

Syntax of YAML format

This format is intented for people not wanting to user the text format above. It supoorts the same parameters as the text format.

For instance:

 # Format: YAML
 ---
 app: popcon
 default:
   defname: foobar
 var: "$var{name} = $args{defname}"
 load: "! MY_HOSTID=$name"

Syntax of Perl format

This format is intended for more complex script where using load instructions is not enough.

This script must then begin with # Format: perl and specifies a hash. For instance:

 # Format: perl
 {
      app => 'popcon', # mandatory
      doc => "Use --arg to_store=a_value to store a_value in MY_HOSTID',
      commit => "control: update Vcs-Browser and Vcs-Git"
      sub => sub ($root, $arg) { $root->fetch_element('MY_HOSTID')->store($arg->{to_store}); }
 }

$root is the root if the configuration tree (See Config::Model::Node). $arg is a hash containing the arguments passed to cme run with -arg options.

The sub parameter value must be a sub ref. Its parameters are $root (a Config::Model::Node object containing the root of the configuration tree) and $arg (a hash ref containing the keys and values passed to cme run with --arg options).

Note that this format does not support var, default and load parameters as you can easily achieve the same result with Perl code.

Options

list

List available scripts and exits.

arg

Arguments for the cme scripts which are used to substitute variables.

doc

Show the script documentation. (Note that --help options show the documentation of cme run command)

cat

Pop the hood and show the content of the script.

commit

Like the commit instruction in script. Specify that the change must be committed with the passed commit message.

no-commit

Don't commit to git (even if the above option is set)

verbose

Show effect of the modify instructions.

Common options

See "Global Options" in cme.

Examples

 $ cme run update-copyright -cat
 app: dpkg-copyright
 load: Files:~ Copyright=~"s/2016,?\s+$name/2017, $name/g"
 commit: updated copyright year of $name

 $ cme run update-copyright -arg "name=Dominique Dumont"
 cme: using Dpkg::Copyright model
 Changes applied to dpkg-copyright configuration:
 - Files:"*" Copyright: '2005-2016, Dominique Dumont <dod@debian.org>' -> '2005-2017, Dominique Dumont <dod@debian.org>'
 - Files:"lib/Dpkg/Copyright/Scanner.pm" Copyright:
 @@ -1,2 +1,2 @@
 -2014-2016, Dominique Dumont <dod@debian.org>
 +2014-2017, Dominique Dumont <dod@debian.org>
   2005-2012, Jonas Smedegaard <dr@jones.dk>

 [master ac2e6410] updated copyright year of Dominique Dumont
  1 file changed, 2 insertions(+), 2 deletions(-)

update VcsGit in debian/control

 $ cme run set-vcs-git  -cat
 doc: update control Vcs-Browser and Vcs-git from git remote value
 doc: parameters: remote (default is origin)
 doc:
 doc: example:
 doc:  cme run set-vcs-git
 doc:  cme run set-vcs-git -arg remote=debian
 
 app: dpkg-control
 default: remote: origin
 
 var: chomp ( $var{url} = `git remote get-url $args{remote}` ) ;
 var: $var{url} =~ s!^git@!https://!;
 var: $var{url} =~ s!(https?://[\w.]+):!$1/!;
 var: $var{browser} = $var{url};
 var: $var{browser} =~ s/.git$//;
 
 load: ! source Vcs-Browser="$browser" Vcs-Git="$url"
 commit: control: update Vcs-Browser and Vcs-Git

This script can also be written using multi line instructions:

 $ cme run set-vcs-git  -cat
 --- doc
 update control Vcs-Browser and Vcs-git from git remote value
 parameters: remote (default is origin)
 
 example:
  cme run set-vcs-git
  cme run set-vcs-git -arg remote=debian
 ---
 
 app: dpkg-control
 default: remote: origin
 
 --- var
 chomp ( $var{url} = `git remote get-url $args{remote}` ) ;
 $var{url} =~ s!^git@!https://!;
 $var{url} =~ s!(https?://[\w.]+):!$1/!;
 $var{browser} = $var{url};
 $var{browser} =~ s/.git$//;
 ---
 
 load: ! source Vcs-Browser="$browser" Vcs-Git="$url"
 commit: control: update Vcs-Browser and Vcs-Git

SEE ALSO

cme

AUTHOR

Dominique Dumont

COPYRIGHT AND LICENSE

This software is Copyright (c) 2014-2022 by Dominique Dumont <ddumont@cpan.org>.

This is free software, licensed under:

  The GNU Lesser General Public License, Version 2.1, February 1999