Create a Jenkins instance in DDC

1_root-docker_start_master.sh

#!/bin/bash

# put this in root/docker_start_master.sh

# Make files owned by jenkins (not root). This didn't work when done from the Dockerfile build.
chown -R jenkins:jenkins /var/jenkins_home
# Need to make sure docker.sock is in the "docker" group so that the "jenkins" user can use it:
chown root:docker /var/run/docker.sock

# Work-around a problem we're having with the container (running as a UCP service) not having DNS set-up:
echo "nameserver 8.8.8.8" >> /etc/resolv.conf

# As user jenkins, call the same command used by the base image jenkins:2.7.4-alpine
su -c '/bin/tini -s -- /usr/local/bin/jenkins.sh' jenkins

2_jenkins-Dockerfile

# We use alpine base because it is smaller than Debian.
FROM jenkins:2.32.2-alpine

USER root

# Need to install the docker binary so that Jenkins can create images and push them.
#
# Since this image uses alpine v3.4, but we need a newer version of docker, we add a v3.5 repository and use it to install docker.
# This is instead of using "RUN apk update && apk add docker".
#
# Note to future maintainers: jenkins:2.7.4-alpine is based on openjdk:8-jdk-alpine which at the time of writing (1/13/2017) is based on alpine 3.4
# A change to base that on Alpine 3.5 was recently reverted and may pop back up. If that does happen, py-pip needs to be renamed to py2-pip
#
RUN echo "@future http://dl-cdn.alpinelinux.org/alpine/v3.5/community" >> /etc/apk/repositories && apk add --update --no-cache \
    docker@future py-pip \
    py-pip

RUN pip install docker-compose

# Create an inode for docker.sock so that it can be volume mounted.
RUN touch /var/run/docker.sock

# Add the existing user (jenkins) to an existing group (docker), adduser is the Alpine/BusyBox way to do it:
RUN adduser jenkins docker

# config.xml is for Jenkins settings
COPY root /root

RUN chmod 700 /root/docker_start_master.sh

ENTRYPOINT ["/root/docker_start_master.sh"]

3_jenkins-build.sh

#!/bin/bash

# in DTR, create a Dais organization, then create a jenkins repo in it

docker build -t dtr.dev.dais.com/dais/jenkins .
docker login dtr.dev.dais.com
docker push dtr.dev.dais.com/dais/jenkins

4_jenkins-service.sh

#!/bin/bash

docker service create --name jenkins -p 30000:8080 -p 50000:50000 \
  --mount "type=bind,source=$PWD/docker/jenkins,target=/var/jenkins_home" \
  --reserve-memory 300m \
  dtr.dev.dais.com/dais/jenkins