Installing Perl modules¶
When there are special requirements then the need for additional Perl modules may arise. Fortunately Perl has an excellent package repository that can satisfy almost all needs. That repository is called CPAN and is available at https://metacpan.org/.
It is recommended that modules from CPAN are installed with the command line client
Alternatively, many Perl modules are also available as packages for your operating system. These
packages can be installed via your systems regular package manager.
cpanm is often already installed on your system.
Please see https://metacpan.org/pod/App::cpanminus for what to do when is isn’t already available.
cpanm installs module into a systemwide location. In this case modules must be installed as the root user.
For example, the command
root> cpanm Acme::Dice
otobo> perldoc -l Acme::Dice /usr/local/share/perl/5.30.0/Acme/Dice.pm
Special care must be taken when OTOBO runs within Docker. In this case, it seems an easy option to install the wanted module into the system Perl.
However, due to how Docker works, this change would be lost when the container is restarted. Therefore the modules must be installed
into a location that survives a restart. The local install location can be specified with the option
--local-lib. Installed modules
will be found by Perl because of the environment variables
PATH, which are set-up accordingly in the Docker image.
otobo> cd /opt/otobo otobo> cpanm --local-lib local Acme::Dice Fetching http://www.cpan.org/authors/id/B/BO/BOFTX/Acme-Dice-1.01.tar.gz ... OK Configuring Acme-Dice-1.01 ... OK Building and testing Acme-Dice-1.01 ... OK Successfully installed Acme-Dice-1.01 1 distribution installed otobo> perldoc -l Acme::Dice /opt/otobo/local/lib/perl5/Acme/Dice.pm otobo: echo $PERL5LIB /opt/otobo_install/local/lib/perl5:/opt/otobo/local/lib/perl5 otobo: echo $PATH /opt/otobo_install/local/bin:/opt/otobo/local/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin