Jenkins master in Docker

001-add-github-key.groovy

import jenkins.model.*
import hudson.model.*
import hudson.security.*
import org.jenkinsci.plugins.*

import com.cloudbees.plugins.credentials.*
import com.cloudbees.plugins.credentials.domains.*
import com.cloudbees.plugins.credentials.common.*
import com.cloudbees.jenkins.plugins.sshcredentials.impl.*

def env = System.getenv()
github_private_key = env['GITHUB_PRIVATE_KEY']

if(github_private_key) {

  global_domain = Domain.global()
  credentials_store =
    Jenkins.instance.getExtensionList('com.cloudbees.plugins.credentials.SystemCredentialsProvider')[0].getStore()

  credentials = new BasicSSHUserPrivateKey(
    CredentialsScope.GLOBAL,
    null,
    "github",
    new BasicSSHUserPrivateKey.DirectEntryPrivateKeySource(github_private_key),
    null,
    "Private key for accessing github"
  )

  username_matcher = CredentialsMatchers.withUsername("github")
  available_credentials =
    CredentialsProvider.lookupCredentials(
      StandardUsernameCredentials.class,
      Jenkins.getInstance(),
      hudson.security.ACL.SYSTEM,
      new SchemeRequirement("ssh")
    )

  existing_credentials =
    CredentialsMatchers.firstOrNull(
      available_credentials,
      username_matcher
    )

  if(existing_credentials != null) {
    credentials_store.updateCredentials(
      global_domain,
      existing_credentials,
      credentials
    )
  } else {
    credentials_store.addCredentials(global_domain, credentials)
  }
}

002-add-seed-job.groovy

import jenkins.model.Jenkins
import hudson.model.FreeStyleProject
import hudson.plugins.git.GitSCM
import hudson.plugins.git.UserRemoteConfig
import hudson.plugins.git.BranchSpec
import hudson.plugins.git.SubmoduleConfig
import hudson.plugins.git.extensions.impl.PathRestriction
import hudson.model.Cause
import hudson.model.Cause.UserIdCause

import javaposse.jobdsl.plugin.ExecuteDslScripts
import javaposse.jobdsl.plugin.RemovedJobAction

import com.cloudbees.plugins.credentials.*
import com.cloudbees.plugins.credentials.domains.*
import com.cloudbees.plugins.credentials.common.*
import com.cloudbees.jenkins.plugins.sshcredentials.impl.*

def env = System.getenv()
seed_jobs_repo = env['SEED_JOBS_REPO']

if(seed_jobs_repo) {
  if(!Jenkins.instance.getItemMap().containsKey("seed-job")) {
    def seedJob = Jenkins.instance.createProject(FreeStyleProject.class, "seed-job")

    username_matcher = CredentialsMatchers.withUsername("github")
    available_credentials =
      CredentialsProvider.lookupCredentials(
        StandardUsernameCredentials.class,
        Jenkins.getInstance(),
        hudson.security.ACL.SYSTEM,
        new SchemeRequirement("ssh")
      )

    existing_credentials =
      CredentialsMatchers.firstOrNull(
        available_credentials,
        username_matcher
      )

    def userRemoteConfig = new UserRemoteConfig(seed_jobs_repo, null, null, existing_credentials.id)

    def scm = new GitSCM(
      Collections.singletonList(userRemoteConfig),
      Collections.singletonList(new BranchSpec("master")),
      false,
      Collections.<SubmoduleConfig>emptyList(),
      null,
      null,
      null)

    scm.getExtensions().add(new PathRestriction("jobs/**/*.*",""))
    seedJob.scm = scm

    def scriptLocation = new ExecuteDslScripts.ScriptLocation("false", "jobs/**/*.groovy", null)
    seedJob.buildersList.add(new ExecuteDslScripts(scriptLocation, false, RemovedJobAction.DELETE))

    seedJob.save()
    seedJob.scheduleBuild(new Cause.UserIdCause())
  }
}

Dockerfile

FROM quay.io/rallysoftware/java:jre8
MAINTAINER "Jonathan Chauncey <jchauncey@rallydev.com>"

RUN yum update all && yum install -y --quiet git tar gcc openssl-devel && yum clean all

ENV JENKINS_HOME /opt/jenkins
RUN mkdir -p /opt/jenkins/plugins

ADD http://mirrors.jenkins-ci.org/war/latest/jenkins.war /opt/jenkins.war

ADD https://updates.jenkins-ci.org/latest/git.hpi /opt/jenkins/plugins/git.hpi
ADD https://updates.jenkins-ci.org/latest/git-client.hpi /opt/jenkins/plugins/git-client.hpi
ADD https://updates.jenkins-ci.org/latest/scm-api.hpi /opt/jenkins/plugins/scm-api.hpi
ADD https://www.dropbox.com/s/m5j02jcf1k209ge/job-dsl.hpi?dl=1 /opt/jenkins/plugins/job-dsl.hpi

ADD https://updates.jenkins-ci.org/latest/ssh-slaves.hpi /opt/jenkins/plugins/ssh-slaves.hpi
ADD https://updates.jenkins-ci.org/latest/ssh-credentials.hpi /opt/jenkins/plugins/ssh-credentials.hpi
ADD https://updates.jenkins-ci.org/latest/credentials.hpi /opt/jenkins/plugins/credentials.hpi
ADD https://updates.jenkins-ci.org/latest/durable-task.hpi /opt/jenkins/plugins/durable-task.hpi

ADD https://updates.jenkins-ci.org/latest/docker-plugin.hpi /opt/jenkins/plugins/docker-plugin.hpi

ADD https://updates.jenkins-ci.org/latest/rbenv.hpi /opt/jenkins/plugins/rbenv.hpi
ADD https://updates.jenkins-ci.org/latest/ruby-runtime.hpi /opt/jenkins/plugins/ruby-runtime.hpi

ADD init.groovy.d /opt/jenkins/init.groovy.d
ADD start.sh /opt/start.sh
RUN chmod +x /opt/start.sh

CMD ["/opt/start.sh"]
EXPOSE 8080

start.sh

#!/bin/bash

java ${JAVA_OPTS} -jar /opt/jenkins.war