Puts image on a diet (Alpine+OpenJDK8)

Dockerfile

@@ -1,46 +1,63 @@
-FROM debian:7.8
+FROM alpine:3.3
 MAINTAINER Mike Babineau [email protected]
 
 ENV \
+    MAVEN_HOME="/usr/share/maven" \
+    JAVA_HOME="/usr/lib/jvm/default-jvm" \
+    JAVA_PREFS="/.java/.userPrefs" \
+    ZK_HOME="/opt/zookeeper" \
+    EXBT_HOME="/opt/exhibitor" \
     ZK_RELEASE="http://www.apache.org/dist/zookeeper/zookeeper-3.4.6/zookeeper-3.4.6.tar.gz" \
     EXHIBITOR_POM="https://raw.githubusercontent.com/Netflix/exhibitor/d911a16d704bbe790d84bbacc655ef050c1f5806/exhibitor-standalone/src/main/resources/buildscripts/standalone/maven/pom.xml" \
-    # Append "+" to ensure the package doesn't get purged
-    BUILD_DEPS="curl maven openjdk-7-jdk+" \
-    DEBIAN_FRONTEND="noninteractive"
+    BUILD_DEPS="curl openjdk8 bash tar"
+
+ENV PATH=${JAVA_HOME}/bin:${PATH}
 
-# Use one step so we can remove intermediate dependencies and minimize size
 RUN \
-    # Install dependencies
-    apt-get update \
-    && apt-get install -y --allow-unauthenticated --no-install-recommends $BUILD_DEPS \
+    # Install Java8
+    apk add --update ${BUILD_DEPS} \
+
+    # Default DNS cache TTL is -1. DNS records, like, change, man
+    && grep '^networkaddress.cache.ttl=' ${JAVA_HOME}/jre/lib/security/java.security || echo 'networkaddress.cache.ttl=60' >> ${JAVA_HOME}/jre/lib/security/java.security \
 
-    # Default DNS cache TTL is -1. DNS records, like, change, man.
-    && grep '^networkaddress.cache.ttl=' /etc/java-7-openjdk/security/java.security || echo 'networkaddress.cache.ttl=60' >> /etc/java-7-openjdk/security/java.security \
+    # Cleanup
+    && rm -rf -- /var/cache/apk/* \
+
+    # Install Maven
+    && MAVEN_VERSION=3.3.3 \
+    && cd /usr/share \
+    && wget -q http://archive.apache.org/dist/maven/maven-3/${MAVEN_VERSION}/binaries/apache-maven-${MAVEN_VERSION}-bin.tar.gz -O - | tar xzf - \
+    && mv /usr/share/apache-maven-${MAVEN_VERSION} /usr/share/maven \
+    && ln -s /usr/share/maven/bin/mvn /usr/bin/mvn
+
+RUN \
+    mkdir -p /opt \
 
     # Install ZK
-    && curl -Lo /tmp/zookeeper.tgz $ZK_RELEASE \
-    && mkdir -p /opt/zookeeper/transactions /opt/zookeeper/snapshots \
-    && tar -xzf /tmp/zookeeper.tgz -C /opt/zookeeper --strip=1 \
+    && curl -Lo /tmp/zookeeper.tgz ${ZK_RELEASE} \
+    && mkdir -p ${ZK_HOME}/transactions ${ZK_HOME}/snapshots \
+    && tar -xzf /tmp/zookeeper.tgz -C ${ZK_HOME} --strip-components=1 \
     && rm /tmp/zookeeper.tgz \
 
     # Install Exhibitor
-    && mkdir -p /opt/exhibitor \
-    && curl -Lo /opt/exhibitor/pom.xml $EXHIBITOR_POM \
-    && mvn -f /opt/exhibitor/pom.xml package \
-    && ln -s /opt/exhibitor/target/exhibitor*jar /opt/exhibitor/exhibitor.jar \
-
-    # Remove build-time dependencies
-    && apt-get purge -y --auto-remove $BUILD_DEPS \
-    && rm -rf /var/lib/apt/lists/*
+    && mkdir -p ${EXBT_HOME} \
+    && curl -Lo ${EXBT_HOME}/pom.xml ${EXHIBITOR_POM} \
+    && mvn -f ${EXBT_HOME}/pom.xml package \
+    && ln -s ${EXBT_HOME}/target/exhibitor*jar ${EXBT_HOME}/exhibitor.jar \
+    && chown -R nobody.nobody ${ZK_HOME} ${EXBT_HOME}
 
 # Add the wrapper script to setup configs and exec exhibitor
-ADD include/wrapper.sh /opt/exhibitor/wrapper.sh
+ADD include/wrapper.sh ${EXBT_HOME}/wrapper.sh
 
 # Add the optional web.xml for authentication
-ADD include/web.xml /opt/exhibitor/web.xml
+ADD include/web.xml ${EXBT_HOME}/web.xml
+
+# To store Java preferences
+RUN mkdir -p ${JAVA_PREFS}
+RUN chown -R nobody.nobody ${JAVA_PREFS}
 
-USER root
+USER nobody
 WORKDIR /opt/exhibitor
 EXPOSE 2181 2888 3888 8181
 
-ENTRYPOINT ["bash", "-ex", "/opt/exhibitor/wrapper.sh"]
+ENTRYPOINT ["bash", "-ex", "/opt/exhibitor/wrapper.sh"]

LICENSE

@@ -19,4 +19,4 @@ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-THE SOFTWARE.
+THE SOFTWARE.

README.md

@@ -4,9 +4,12 @@ Available on the Docker Index as [mbabineau/zookeeper-exhibitor](https://index.d
 
     docker pull mbabineau/zookeeper-exhibitor
 
+The image is based on Alpine Linux and is ~272MB.
+
 ### Versions
 * Exhibitor 1.5.5
 * ZooKeeper 3.4.6
+* Java 1.8
 
 ### Usage
 The container expects the following environment variables to be passed in: