How to remotely debug WSO2 product which is in a docker container.

This post contains how to debug a docker container. As per the prerequisites, users have to clone two WSO2 repos along the road. Other than that he or she should have good knowledge in remote debugging. Without further due let's start the process.

First clone and download the Puppet modules for WSO2 products.

https://github.com/wso2/puppet-modules.git

Move to the v2.1.0 tag

Add the product pack and JDK to following locations.

 Download and copy JDK 1.7 (jdk-7u80-linux-x64.tar.gz) pack to below directory.

<PUPPET_HOME>/modules/wso2base/files

 Download the relevant product pack and copy them to below directory.

<PUPPET_HOME>/modules/wso2greg/files

 Then clone WSO2 Dockerfiles

https://github.com/wso2/dockerfiles.git

Now set puppet home using below terminal command. 

export PUPPET_HOME=<puppet_modules_path>

 Example:

export PUPPET_HOME=/Users/thushara/Documents/greg/wso2/puppet-modules

Update the following lines in entrypoint.sh

<dockerfiles_home>/common/scripts/entrypoint.sh

Example:

echo "Starting ${SERVER_NAME} with [Startup Args] ${STARTUP_ARGS}, [CARBON_HOME] ${CARBON_HOME}"
${CARBON_HOME}/bin/wso2server.sh start
sleep 10s
tail -500f ${CARBON_HOME}/repository/logs/wso2carbon.log

Lets install Vim in the docker container for debugging purposes. For that add following lines to Dockerfile, before last 2 lines.

<dockerfiles_home>/wso2greg/Dockerfile

RUN apt-get install -y vim

Now update the following line to open remote debug ports.

<dockerfiles_home>/wso2greg/run.sh

Example:

bash ${common_folder}/docker-run.sh -n ${product_name} -p 9763:9763 -p 9443:9443 -p 5005:5005 $*

Thats it with the configuration now you can build and start docker container to start debugging.

First build the docker container,

<dockerfiles_home>/wso2greg $ bash build.sh -v 5.2.0 -r puppet

Now run the docker container,

<dockerfiles_home>/wso2greg $ bash run.sh -v 5.2.0

To find the docker container name please list all the docker processes running using below command,

<dockerfiles_home>/wso2greg $ docker ps

Let's login to the docker instance using image name(wso2greg-default) which we got using docker ps command.

<dockerfiles_home>/wso2greg $ docker exec -it wso2greg-default /bin/bash

Now you can start remote debugging as you use to it :)

Below I have added additional commands you might need. To see the list of docker machines up and running use below commands,

<dockerfiles_home>/wso2greg $ docker-machine ls

That's it from here. If you have any questions please create a StackOverflow question and attached it as a comment below.