jenkins – Systems Lab

November 8, 2020October 18, 2020

Jenkins LDAP Authentication

Continuing on my journey through centralizing my authentication for a number of services, I come to my Jenkins instance. This was setup recently to handle CI/CD on some of my personal projects, and has been working extremely well on automated build/test/deploy. Since none of the software it supports is going anywhere anytime soon, I decided to add the instance to the grouping of services going to LDAP for authentication. Setting up Jenkins with LDAP is a relatively straight forward process. It requires a few plugins to support it fully (authentication, group based authorization). The difficulty comes in authorization, as the role-based authorization strategy plugin isn’t as well documented as one would hope. It is at least not too hard to work through and works as intended.

Plugins to Use

LDAP Plugin
- Default Plugin included in Jenkins
Role-Based Authorization Strategy
Authorize Project

August 30, 2020

Automated Testing in Jenkins

After setting up Jenkins to auto build and deploy my IRC bots, I decided to add the next component of a CI/CD stack, automated testing. This was to use ant to run the tests, and JUnit for the testing framework for the application. I’ll be setting this up in both of my Jenkins projects, I have one that just builds my applications, and a second that builds the docker containers and pushes them to the repository.

My Jenkins setup includes 2 builds for each of my projects:

Java Build
- Builds the java application
- This is just a general Jenkins project that uses ant to build
Docker Build
- Builds the docker container, tags it, and pushes it to my local docker repository
- This uses Jenkins pipelines to perform the build, tag, push

The docker build pushes my production code and is used by my docker-swarm to update my locally built containers. This is the important build. The general java build is just me experimenting with Jenkins builds following the non-pipeline route.

August 29, 2020August 29, 2020

Jenkins Docker Revisit

After my initial jenkins setup, I thought my system would be good to go for a long time, however I encountered a problem with permissions after my docker cluster reboot. After all my nodes were back up, and jenkins was running, it could no longer access the docker.sock that it used to handle building and pushing containers. I tried a few things, rebuilding the container, updating it, changing some groups, and found quite a few threads on the topic. Some people had chmod’d the docker.sock to 777 (BAD) or had given jenkins root (ALSO BAD). I ended up finding the solution in using a specific entrypoint script that would determine the group to add to the jenkins user, then launch jenkins using the jenkins user from root.

Most of my additions are from sudo-bmitch’s jenkins-docker repository on GitHub. These include the dockerfile changes and the entrypoint.sh script (as well as the healthcheck mentioned later on).

August 8, 2020August 29, 2020

IRC Botnet and Jenkins

I wrote a number of IRC bots a number of years ago, hosting them on my infrastructure. Since building a 3 node docker swarm, I decided that these would be good candidates to use in learning Jenkins for both auto building the software, and building containers. I hadn’t made my own dockerfiles before, nor had I setup proper builds outside of my IDE for these bots before.