Merge pull request jenkinsci#7 from carlossg/size

Reduce image size cleaning up apt and avoid unnecessary updates

Author: michaelneale

Dockerfile

@@ -2,16 +2,16 @@ FROM ubuntu:14.04
 
 RUN echo "1.565.2" > .lts-version-number
 
-RUN apt-get update && apt-get install -y wget git curl zip
-RUN apt-get update && apt-get install -y --no-install-recommends openjdk-7-jdk
-RUN apt-get update && apt-get install -y maven ant ruby rbenv make
+RUN apt-get update && apt-get install -y wget git curl zip && apt-get clean
+RUN apt-get update && apt-get install -y --no-install-recommends openjdk-7-jdk && apt-get clean
+RUN apt-get update && apt-get install -y maven ant ruby rbenv make && apt-get clean
 
 RUN wget -q -O - http://pkg.jenkins-ci.org/debian-stable/jenkins-ci.org.key | sudo apt-key add -
 RUN echo deb http://pkg.jenkins-ci.org/debian-stable binary/ >> /etc/apt/sources.list
 RUN apt-get update && apt-get install -y jenkins
 RUN mkdir -p /var/jenkins_home && chown -R jenkins /var/jenkins_home
 ADD init.groovy /tmp/WEB-INF/init.groovy
-RUN cd /tmp && zip -g /usr/share/jenkins/jenkins.war WEB-INF/init.groovy
+RUN cd /tmp && zip -g /usr/share/jenkins/jenkins.war WEB-INF/init.groovy && rm -rf /tmp/WEB-INF
 ADD ./jenkins.sh /usr/local/bin/jenkins.sh
 RUN chmod +x /usr/local/bin/jenkins.sh
 USER jenkins