docker-alpine-java

Simple docker image with java JDK installed

We will create a docker image for a JAVA Application (Simple or not)

[Note]

• First of all we will add custom JDK because sometime we MUST use a specific one

[Pre requisite]

• Docker installed

• for execute script Docker deamon must be started : dockerd with --iptables=false

A - Create a docker file

Who begin by that:

# Dockerfile
FROM  alpine:3.5

MAINTAINER  Author Name <[email protected]>

ENV JAVA_VERSION=8 
JAVA_UPDATE=144 
JAVA_BUILD=01
JAVA_PATH=090f390dda5b47b9b721c7dfaa008135    
JAVA_HOME=/usr/lib/jvm/default-jvm

1. Update the package repository

#Upgrading system on alpine
RUN apk upgrade
RUN apk add wget

2. Add JDK Openjdk jre

RUN apk add openjdk8-jre-base --update-cache --repository http://dl-3.alpinelinux.org/alpine/edge/testing/ --allow-untrusted \
&& rm -rf /var/cache/apk/*

2 bis . Add Oracle JDK (Warning mabe this solution not working)

RUN apk add --no-cache --virtual=build-dependencies wget ca-certificates unzip && cd "/tmp" && wget --header "Cookie: oraclelicense=accept-securebackup-cookie;" "http://download.oracle.com/otn-pub/java/jdk/${JAVA_VERSION}u${JAVA_UPDATE}-b${JAVA_BUILD}/${JAVA_PATH}/jdk-${JAVA_VERSION}u${JAVA_UPDATE}-linux-x64.tar.gz" && tar -xzf "jdk-${JAVA_VERSION}u${JAVA_UPDATE}-linux-x64.tar.gz" && mkdir -p "/usr/lib/jvm" && mv "/tmp/jdk1.${JAVA_VERSION}.0_${JAVA_UPDATE}" "/usr/lib/jvm/java-${JAVA_VERSION}-oracle" && ln -s "java-${JAVA_VERSION}-oracle" "$JAVA_HOME" && ln -s "$JAVA_HOME/bin/"* "/usr/bin/" && rm -rf "$JAVA_HOME/"*src.zip && wget --header "Cookie: oraclelicense=accept-securebackup-cookie;" "http://download.oracle.com/otn-pub/java/jce/${JAVA_VERSION}/jce_policy-${JAVA_VERSION}.zip" && unzip -jo -d "${JAVA_HOME}/jre/lib/security" "jce_policy-${JAVA_VERSION}.zip" && rm "${JAVA_HOME}/jre/lib/security/README.txt" && apk del build-dependencies && rm "/tmp/"*

3. Expose Container VOLUME

#Expose volume
VOLUME /app
VOLUME /tmp

4. Clean your image

RUN rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*

5. Add your Java/SpringBoot component

#The gs-spring-boot-docker-0.1.0.jar must be in the same directory as the docker file

ADD gs-spring-boot-docker-0.1.0.jar app.jar
RUN sh -c 'touch /app.jar'
#Set your entrypoint
ENTRYPOINT ["java","-Djava.security.egd=file:/dev/./urandom","-jar","/app.jar"]

B - Create docker image from docker file

$ docker build -f Dockerfile -t demo/spring-java:8 --rm=true .

The "." is mandatory :) do not forget it !!!!

C - RUN the docker image freshly created

$ docker run -p 8080:8080 -t demo/spring-java:8

Or

$ docker run -p 8080:8080 -t demo/spring-java:8 <map Volume for log for example>