Versions Compared

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.

...

Code Block
languagebash
titleDockerfile for Controller Image
linenumberstrue
collapsetrue
# BUILD PRE-IMAGE

FROM alpine:latest AS js7-pre-image

# provide build arguments for release information
ARG JS_RELEASE
ARG JS_RELEASE_MAJOR

# add/copy installation tarball
ADD https://download.sos-berlin.com/JobScheduler.${JS_RELEASE_MAJOR}/js7_controller_unix.${JS_RELEASE}.tar.gz /usr/local/src/
# COPY js7_controller_unix.${JS_RELEASE}.tar.gz /usr/local/src/

RUN mkdir -p /var/sos-berlin.com/js7 && \
    test -e /usr/local/src/js7_controller_unix.${JS_RELEASE}.tar.gz && \
    tar xfvz /usr/local/src/js7_controller_unix.${JS_RELEASE}.tar.gz -C /var/sos-berlin.com/js7/

# add entrypoint script and start script
COPY entrypoint.sh /var/sos-berlin.com/js7/
COPY start-controller.sh /var/sos-berlin.com/js7/

# copy configuration
COPY config/ /var/sos-berlin.com/js7/controller/var/config/

# BUILD IMAGE

FROM alpine:latest AS js7-image

LABEL maintainer="Software- und Organisations-Service GmbH"

# provide build arguments for release information
ARG JS_RELEASE
ARG JS_RELEASE_MAJOR

# image user id has to match later run-time user id
ARG JS_USER_ID=${JS_USER_ID:-1001}
ARG JS_ID=${JS_ID:-jobscheduler}
ARG JS_HTTP_INTERFACE=${JS_HTTP_INTERFACE:-""}
ARG JS_HTTP_PORT=${JS_HTTP_PORT:-4444}
ARG JS_HTTPS_INTERFACE=${JS_HTTPS_INTERFACE:-""}
ARG JS_HTTPS_PORT=${JS_HTTPS_PORT:-""}
ARG JS_JAVA_OPTIONS=${JS_JAVA_OPTIONS}

# JS7 user id, Controller ID, ports and Java optionsa
ENV RUN_JS_USER_ID=${RUN_JS_USER_ID:-1001}
ENV RUN_JS_ID=${RUN_JS_ID:-$JS_ID}
ENV RUN_JS_HTTP_INTERFACE=${RUN_JS_HTTP_INTERFACE:-$JS_HTTP_INTERFACE}
ENV RUN_JS_HTTP_PORT=${RUN_JS_HTTP_PORT:-$JS_HTTP_PORT}
ENV RUN_JS_HTTPS_INTERFACE=${RUN_JS_HTTPS_INTERFACE:-$JS_HTTPS_INTERFACE}
ENV RUN_JS_HTTPS_PORT=${RUN_JS_HTTPS_PORT}
ENV RUN_JS_JAVA_OPTIONS=${RUN_JS_JAVA_OPTIONS:-$JS_JAVA_OPTIONS}

COPY --from=js7-pre-image ["/var/sos-berlin.com/js7", "/var/sos-berlin.com/js7"]

# INSTALLATION

# install process tools, net tools, bash, openjdk
# add jobscheduler user account and make it the owner of directories
# for JDK < 12, /dev/random does not provide sufficient entropy, see https://kb.sos-berlin.com/x/lIM3
RUN apk update && apk add --no-cache \
    --repository=http://dl-cdn.alpinelinux.org/alpine/edge/community \
    procps \
    net-tools \
    bash \
    shadow \
    openjdk8 && \
    adduser -u ${JS_USER_ID:-1001} --disabled-password --home /home/jobscheduler --shell /bin/bash jobscheduler jobscheduler && \
    chown -R jobscheduler:jobscheduler /var/sos-berlin.com && \
    mv /var/sos-berlin.com/js7/entrypoint.sh /usr/local/bin/ && \
    mv /var/sos-berlin.com/js7/start-controller.sh /usr/local/bin/ && \
    chmod +x /usr/local/bin/entrypoint.sh /usr/local/bin/start-controller.sh && \
    sed -i 's/securerandom.source=file:\/dev\/random/securerandom.source=file:\/dev\/urandom/g' /usr/lib/jvm/java-1.8-openjdk/jre/lib/security/java.security

# START

ENTRYPOINT ["sh", "/usr/local/bin/entrypoint.sh"]

CMD ["/usr/local/bin/start-controller.sh", "--id=\"$RUN_JS_ID\"", "--http-port=$RUN_JS_HTTP_INTERFACE:$RUN_JS_HTTP_PORT", "--https-port=$RUN_JS_HTTPS_INTERFACE:$RUN_JS_HTTPS_PORT", "--java-options=\"$RUN_JS_JAVA_OPTIONS\""]

...

  • The build script implements two stages to exclude installer files from the resulting image.
  • Line 3: The base image is the current Alpine image at build-time.
  • Line 6 - 7: The release identification is injected by build arguments. This information is used to determine the tarball to be downloaded or copied.
  • Line 10 - 11: You can either download the Controller tarball directly from the SOS web site or you store the tarball with the build directory and copy from this location.
  • Line 13 - 15: The tarball is extracted. For Unix Controllers no installer is used.

  • Line 18: The entrypoint.sh script is copied from the build directory to the image. Users can apply their own version of the entrypoint script. The start script used by SOS looks like this:
    Download: entrypoint.sh

    Code Block
    languagebash
    titleController Entrypoint Script
    linenumberstrue
    collapsetrue
    #!/bin/sh
    
    JS_USER_ID=`echo $RUN_JS_USER_ID | cut -d ':' -f 1`
    JS_GROUP_ID=`echo $RUN_JS_USER_ID | cut -d ':' -f 2`
    
    BUILD_GROUP_ID=`cat /etc/group | grep jobscheduler | cut -d ':' -f 3`
    BUILD_USER_ID=`cat /etc/passwd | grep jobscheduler | cut -d ':' -f 4`
    
    if [ "$(id -u)" = "0" ]
    then
      if [ ! "$BUILD_USER_ID" = "$JS_USER_ID" ]
      then
        echo "JS7 entrypoint script preparing switch of image user id '$BUILD_USER_ID' -> '$JS_USER_ID', group id '$BUILD_GROUP_ID' -> '$JS_GROUP_ID'"
        sedusermod -i "s/$BUILD_GROUP_ID/u $JS_USER_ID jobscheduler
        groupmod -g $JS_GROUP_ID/g" /etc/group jobscheduler
        sedfind /var/sos-berlin.com/ -igroup "s/$BUILD_USER_ID:$BUILD_GROUP_ID/$JS_USER_ID:$JS_GROUP_ID/g" /etc/passwd -exec chgrp -h jobscheduler {} \;
        find /var/sos-berlin.com/ -user $BUILD_USER_ID -exec chown -h jobscheduler {} \;
      fi
    
      echo "JS7 entrypoint script switching to user account 'jobscheduler' to run start script"
      exec su jobscheduler -c "$*"
    else
      if [ "$BUILD_USER_ID" = "$JS_USER_ID" ]
      then
        if [ "$(id -u)" = "$JS_USER_ID" ]
        then
          echo "JS7 entrypoint script running for user id '$(id -u)'"
        else
          echo "JS7 entrypoint script running for user id '$(id -u)' cannot switch to user id '$JS_USER_ID', group id '$JS_GROUP_ID'"
          echo "JS7 entrypoint script missing permission to switch user id and group id, consider to omit the 'docker run --user' option"
        fi
      else
        echo "JS7 entrypoint script running for user id '$(id -u)' cannot switch image user id '$BUILD_USER_ID' -> '$JS_USER_ID', group id '$BUILD_GROUP_ID' -> '$JS_GROUP_ID'"
        echo "JS7 entrypoint script missing permission to switch user id and group id, consider to omit the 'docker run --user' option"
      fi
    
      exec sh -c "$*"
    fi
    
  • Line 19: The start-controller.sh script is copied from the build directory to the image. Users can apply their own version of the start script. The start script used by SOS looks like this:
    Download: start-controller.sh

    Code Block
    languagebash
    titleController Start Script
    linenumberstrue
    collapsetrue
    #!/bin/sh
    
    js_id=""
    js_http_port=""
    js_https_port=""
    js_java_options=""
    
    for option in "$@"
    do
      case "$option" in
             --id=*)           js_id=`echo "$option" | sed 's/--id=//'`
                               ;;
             --http-port=*)    js_http_port=`echo "$option" | sed 's/--http-port=//'`
                               ;;
             --https-port=*)   js_https_port=`echo "$option" | sed 's/--https-port=//'`
                               ;;
             --java-options=*) js_java_options=`echo "$option" | sed 's/--java-options=//'`
                               ;;
             *)                echo "unknown argument: $option"
                               exit 1
                               ;;
      esac
    done
    
    js_args=""
    
    if [ ! "$js_http_port" = "" ] && [ ! "$js_http_port" = ":" ]
    then
      js_args="$js_args --http-port=$js_http_port"
    fi
    
    if [ ! "$js_https_port" = "" ] && [ ! "$js_https_port" = ":" ]
    then
      js_args="$js_args --https-port=$js_https_port"
    fi
    
    if [ ! "$js_java_options" = "" ]
    then
      js_args="$js_args --java-options=$js_java_options"
    fi
    
    echo "starting Controller: /var/sos-berlin.com/js7/controller/bin/controller.sh start --id=$js_id $js_args"
    /var/sos-berlin.com/js7/controller/bin/controller.sh start --id=$js_id $js_args && tail -f /dev/null
  • Line 22: The config folder available in the build directory is copied to the config sub-folder in the image. This can be useful to create an image with individual default settings in configuration files, see JS7 - Controller Configuration Items.
  • Line 35 - 41: Defaults for the Controller ID and user id running the Controller inside the container as well as HTTP and HTTPS ports are provided. These values can be overwritten by providing the respective build arguments.
  • Line 44 - 50: Environment variables are provided at run-time, not at build-time. They can be used to specify ports and Java options when running the container.
  • Line 59 - 63: The image OS is updated and additional packages are installed (ps, netstat, bash,).
  • Line 6465: The most recent Java 1.8 package available with Alpine is applied. Controllers can be operated with newer Java releases, however, stick to Oracle, OpenJDK or AdoptOpenJDK as the source for your Java LTS release. Alternatively you can use your own base image and install Java 1.8 or later on top of this.
  • Line 65 66 - 6970: The user account jobscheduler is created and is assigned the user id and group id handed over by the respective build arguments. This translates to the fact that the account running the Controller inside the container and the account that starts the container are assigned the same user id and group id. This allows the account running the container to access any files created by the Controller in mounted volumes with identical permissions.
  • Line 7071: Java releases < Java 12 make use of /dev/random for random number generation. This is a bottleneck as random number generation with this file is blocking. Instead /dev/urandom should be used that implements non-blocking behavior. The change of the random file is applied to the Java security file.
  • Line 7475-7677: The entrypoint script and start script is executed and is dynamically parameterized from environment variables that are forwarded when starting the container.

...