prashanthmadi/appserviceperl repository overview

Azure has recently announced App Services on Linux⁠. It supports running web apps natively on Linux. You can quickly create an app following Link⁠ and setup continuous deployment to publish the app.

Web Apps on Linux is built using Docker⁠. So you can use a Custom Docker image to deploy your web app to an application stack that is not already defined in Azure - Link⁠

This Blog would provide an overview of Creating and running Custom Container to run perl application in web apps on Linux.

⁠Creating Custom Perl Container

1. I would recommend to setup a local Docker dev environment for creating Custom container(makes it easy to debug). Refer my another blog Running Docker on Azure VM⁠
2. Make sure your Docker file is running as expected in development environment
3. Deploy your Docker files into Github. Ex: appserviceperl⁠
4. Create DockerHub account and Setup Continuous integration from Github

Below are list of steps my DockerFile has to create App Service Perl image Github Repo : https://github.com/prashanthmadi/appserviceperl⁠

• I have extended httpd official container and set custom httpd.conf file

FROM httpd:2.4
COPY ./my-httpd.conf /usr/local/apache2/conf/httpd.conf

• Established symlinks for below as all our site content would be in /home/site/wwwroot folder
  /usr/local/apache2/htdocs -> /home/site/wwwroot
  /usr/local/apache2/logs -> /home/LogFiles
  

RUN  rm -f /usr/local/apache2/logs/* \
   && chmod 777 /usr/local/apache2/logs \
   && rm -rf /usr/local/apache2/htdocs \
   && rm -rf /usr/local/apache2/logs \
   && mkdir -p /home/site/wwwroot \
   && mkdir -p /home/LogFiles \
   && chown -R root:www-data /home \
   && ln -s /home/site/wwwroot /usr/local/apache2/htdocs \
   && ln -s /home/LogFiles /usr/local/apache2/logs

• Installed perl again as cpanm fails with default installation.

RUN apt-get update \
   && apt-get install make \
   && apt-get install -y perl

• Created a /home/cpan directory for temporary use and need to be deleted later

RUN mkdir -p /home/cpan

• Copied cpanfile to /home/cpan/cpanfile. this file has required perl dependencies. You can alter this as per your requirement.

COPY ./cpanfile /home/cpan/cpanfile

• Download cpanm inside /home/cpan folder and insall modules listed in cpanfile

RUN apt-get install -y curl \
   && cd /home/cpan \
   && curl -LO http://xrl.us/cpanm \
   && apt-get install -y libhtml-parser-perl \
   && perl cpanm --force --installdeps .

• deleting /home/cpan folder as we don't need it anymore

RUN rm -rf /home/cpan

####Installing Custom Container to run Perl App on Web Apps Linux

• Navigate to azure portal and select "Web App On Linux" option inside Web + Mobile
• We need to Select "Configure container" option to use Custom Container
• Here you can use Built-in container or one from Docker Hub/Private registry
• I have my Perl Custom Container @ Docker Hub - prashanthmadi/appserviceperl⁠
• So, I have selected Docker Hub and entered my Image name.
• Finish the process by pressing Create Button

####Testing App:

• Create a index.pl file with below content and deploy it using FTP/Git.

#!/usr/bin/perl -w
print "Content-type: text/html\n\n";
print "Hello, World.";

• Navigate to http://<your_webapp_name>.azurewebsites.net/ and it should show "Hello World"

####Extending Custom Container to install more Perl dependencies For adding extra modules, make a fork of my github repo. https://github.com/prashanthmadi/appserviceperl⁠

change content in cpanfile (samples available at below link)… https://github.com/kraih/mojo/wiki/Installation-of-cpan-modules-by-cpanm-and-cpanfile⁠

Publish your new project to dockerhub and use it while configuring container.