Dockerfile Example

Dockerfile

# MINIMAL DOCKER IMAGE FOR RUNNING A MICROSERVICE

FROM ohmygoshjosh/busybox
MAINTAINER Josh Padnick <josh@tinysteps.co>

# MICROSERVICE ENV VARS
# ------------------------------------------------------------------------------
ENV MICROSERVICE_NAME lemon

# INSTALL JAVA
# Inspired by https://registry.hub.docker.com/u/jeanblanchard/busybox-java/dockerfile/
# ------------------------------------------------------------------------------

# Install cURL
RUN opkg-install curl

# Java Version
ENV JAVA_VERSION_MAJOR 8
ENV JAVA_VERSION_MINOR 31
ENV JAVA_VERSION_BUILD 13
ENV JAVA_PACKAGE       server-jre

# Copy all checksums from local to the container
# To compute a new checksum in the future...
# - Log into busybox with "docker run -it ohmygoshjosh/busybox" (run this on localdev)
# - Download the new file
# - "sha256sum <new-file_name>"
# - Write the new checksum into the appropriately named file in deploy/checksums
# TIP: For Java, note that we compute the checksum on the .tar and NOT the .tar.gz file!
# TIP: Be sure to copy the entire output of "sha256sum", not just the SHA itself.
COPY deploy/checksums checksums

# Download and unarchive Java
RUN curl -kLOH "Cookie: gpw_e24=http%3A%2F%2Fwww.oracle.com%2F; oraclelicense=accept-securebackup-cookie"\
  http://download.oracle.com/otn-pub/java/jdk/${JAVA_VERSION_MAJOR}u${JAVA_VERSION_MINOR}-b${JAVA_VERSION_BUILD}/${JAVA_PACKAGE}-${JAVA_VERSION_MAJOR}u${JAVA_VERSION_MINOR}-linux-x64.tar.gz &&\
    gunzip ${JAVA_PACKAGE}-${JAVA_VERSION_MAJOR}u${JAVA_VERSION_MINOR}-linux-x64.tar.gz &&\
    [ "$(cat /checksums/${JAVA_PACKAGE}-${JAVA_VERSION_MAJOR}u${JAVA_VERSION_MINOR}-linux-x64.tar.sha256)" = "$(sha256sum ${JAVA_PACKAGE}-${JAVA_VERSION_MAJOR}u${JAVA_VERSION_MINOR}-linux-x64.tar)" ] &&\
    tar -xf ${JAVA_PACKAGE}-${JAVA_VERSION_MAJOR}u${JAVA_VERSION_MINOR}-linux-x64.tar -C /opt &&\
    rm ${JAVA_PACKAGE}-${JAVA_VERSION_MAJOR}u${JAVA_VERSION_MINOR}-linux-x64.tar &&\
    ln -s /opt/jdk1.${JAVA_VERSION_MAJOR}.0_${JAVA_VERSION_MINOR} /opt/jdk &&\
    rm -rf /opt/jdk/*src.zip \
           /opt/jdk/lib/missioncontrol \
           /opt/jdk/lib/visualvm \
           /opt/jdk/lib/*javafx* \
           /opt/jdk/jre/lib/plugin.jar \
           /opt/jdk/jre/lib/ext/jfxrt.jar \
           /opt/jdk/jre/bin/javaws \
           /opt/jdk/jre/lib/javaws.jar \
           /opt/jdk/jre/lib/desktop \
           /opt/jdk/jre/plugin \
           /opt/jdk/jre/lib/deploy* \
           /opt/jdk/jre/lib/*javafx* \
           /opt/jdk/jre/lib/*jfx* \
           /opt/jdk/jre/lib/amd64/libdecora_sse.so \
           /opt/jdk/jre/lib/amd64/libprism_*.so \
           /opt/jdk/jre/lib/amd64/libfxplugins.so \
           /opt/jdk/jre/lib/amd64/libglass.so \
           /opt/jdk/jre/lib/amd64/libgstreamer-lite.so \
           /opt/jdk/jre/lib/amd64/libjavafx*.so \
           /opt/jdk/jre/lib/amd64/libjfx*.so

# Set environment vars
ENV JAVA_HOME /opt/jdk
ENV PATH ${PATH}:${JAVA_HOME}/bin

# INSTALL TYPESAFE ACTIVATOR AND GENERATE THE SERVICE'S BIN FILE
# ------------------------------------------------------------------------------

# Typesafe Activator Version
ENV ACTIVATOR_VERSION 1.2.12

# Copy all our microservice's source code into the container
COPY api/ /app/

# Add the "tinysteps" group and user
RUN adduser -D -H tinysteps tinysteps

# The activator file is ~350MB. When dealing with Docker locally, it's preferable to uncomment this line
# Note that you'll also need to comment out the "wget http://downloads.typesafe..." line from the RUN command
# COPY deploy/downloads/ /opt

# Set the working directory
WORKDIR /opt

# Download the full version of Typesafe Activator (contains all Play Framework libraries)
RUN wget http://downloads.typesafe.com/typesafe-activator/${ACTIVATOR_VERSION}/typesafe-activator-${ACTIVATOR_VERSION}.zip &&\
    [ "$(cat /checksums/typesafe-activator-${ACTIVATOR_VERSION}.zip.sha256)" = "$(sha256sum typesafe-activator-${ACTIVATOR_VERSION}.zip)" ] &&\
    unzip -o typesafe-activator-${ACTIVATOR_VERSION}.zip &&\
    chown tinysteps:tinysteps /opt/activator-${ACTIVATOR_VERSION} &&\

    # Create the binary executable that runs our service and delete unneeded files
    cd /app &&\
    /opt/activator-${ACTIVATOR_VERSION}/activator dist &&\
    cd /app/target/universal &&\
    unzip /app/target/universal/${MICROSERVICE_NAME}-1.0-SNAPSHOT.zip &&\
    mv /app/target/universal /app-run &&\
    chown -R tinysteps:tinysteps /app-run &&\

    # Clean up all our files
    rm -Rf /app &&\
    rm /opt/typesafe-activator-${ACTIVATOR_VERSION}.zip &&\
    rm -Rf /opt/activator-${ACTIVATOR_VERSION} &&\
    rm -Rf /root/.ivy2

# Tell Docker that port 9001 should be exposed from this container
EXPOSE 9001

# The container's job in life is to run this command
CMD /app-run/${MICROSERVICE_NAME}-1.0-SNAPSHOT/bin/${MICROSERVICE_NAME} -Dhttp.port=9001