making a docker for running perl

With the helps of docker, we can make an image to have all needed perl packages installed, and run this image from everywhere.

Here I give a basic sample for building a docker for perl development.

Say the project name is "gmbox", which uses a special package Gmail::Mailbox::Validate to work.

First we create a dir named as "gmbox", and put Dockerfile under this dir.

 $ mkdir gmbox
 $ touch gmbox/Dockerfile

The next step we want to edit Dockerfile and put the following content into it.

 FROM perl
   
 LABEL maintainer=@pyh
   
 RUN apt update && apt install -y cpanminus && cpanm Gmail::Mailbox::Validate

Here are the comments to Dockerfile above.

FROM - define the base image from Dockerhub, here is perl.
LABEL - define some labels to identify this image.
RUN - run the special commands to make the image, i.e, install some packages.

In the RUN section, we run apt to install cpanminus firstly, then install Gmail::Mailbox::Validate via cpanminus.

The next step we want to run "docker build" for buiding that image.

 $ docker build -t gmbox gmbox

Here -t specify the name for docker image, the last argument points to the dir which has Dockerfile included.

After successful building we will see the output:

 ...
  ---> 111b725bb261
 Successfully built 111b725bb261
 Successfully tagged gmbox:latest

Hence we can list the image just built:

 $ docker image ls
 REPOSITORY               TAG       IMAGE ID       CREATED              SIZE
 gmbox                    latest    111b725bb261   About a minute ago   921MB

How to run this docker image? Let's make a script and put it into "bin" dir under current dir.

 $ cat bin/gmbox.pl 
 use Gmail::Mailbox::Validate;
 use strict;
    
 my $username = shift || die "$0 username\n";
   
 my $v = Gmail::Mailbox::Validate->new();
 print  $v->validate($username) ? "$username exists\n" : "$username not exists\n";

Finally we run this script using the docker image.

 $  docker run -v `pwd`:/home gmbox perl /home/bin/gmbox.pl johnsmart
 johnsmart exists
   
 $  docker run -v `pwd`:/home gmbox perl /home/bin/gmbox.pl johndoe
 johndoe not exists

The -v option maps current dir (`pwd`) to docker's /home dir. So the script's path in docker is "/home/bin/gmbox.pl".

And the running results are printed out to screen.

All done with this way.

Return to home | Generated on 09/29/22