Introduction

This article describes the build process for official JOC Cockpit images.
Users can build their own container images for JOC Cockpit and adjust to their needs.

Build Environment

The following directory hierarchy is assumed for the build environment:

joc
- build.sh
- build
  - Dockerfile
  - entrypoint.sh
  - jetty.sh
  - js7_install_joc.sh
  - config

The joc root directory can have any name. The build files listed above are available for download. Note that the build script described below will, by default, use the directory name and release number to determine the resulting image name.

Dockerfile

Download: Dockerfile

Container images for JS7 JOC Cockpit provided by SOS make use of the following Dockerfile:

Dockerfile for JOC Cockpit Image

# BUILD PRE-IMAGE

FROM alpine:3.20 AS js7-pre-image

# 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=${JS_USER_ID:-1001}
ARG JS_HTTP_PORT=${JS_HTTP_PORT:-4446}
ARG JS_HTTPS_PORT=${JS_HTTPS_PORT:-4443}
ARG JS_JAVA_OPTIONS=${JS_JAVA_OPTIONS}

# add/copy installation tarball
# ADD https://download.sos-berlin.com/JobScheduler.${JS_RELEASE_MAJOR}/js7_joc_linux.${JS_RELEASE}.tar.gz /usr/local/src/
COPY js7_joc_linux.${JS_RELEASE}.tar.gz /usr/local/src/

# test installer tarball
RUN test -e /usr/local/src/js7_joc_linux.${JS_RELEASE}.tar.gz

# add/copy installer script
# ADD  https://download.sos-berlin.com/JobScheduler.${JS_RELEASE_MAJOR}/js7_install_joc.sh /usr/local/bin/
COPY js7_install_joc.sh /usr/local/bin/

# copy configuration
COPY config/ /usr/local/src/resources

# install Java and JOC Cockpit
#   create user account jobscheduler using root group
RUN apk upgrade --available && apk add --no-cache \
    openjdk17-jre && \
    sed -i 's/securerandom.source=file:\/dev\/random/securerandom.source=file:\/dev\/urandom/g' /usr/lib/jvm/java-17-openjdk/conf/security/java.security && \
    adduser -u ${JS_USER_ID} -G root --disabled-password --home /home/jobscheduler --shell /bin/bash jobscheduler && \
    chmod +x /usr/local/bin/js7_install_joc.sh && \
    printf "http port %s https port %s \n", "${JS_HTTP_PORT}", "${JS_HTTPS_PORT}" && \
    /usr/local/bin/js7_install_joc.sh \
        --home=/opt/sos-berlin.com/js7/joc \
        --data=/var/sos-berlin.com/js7/joc \
        --setup-dir=/usr/local/src/joc.setup \
        --tarball=/usr/local/src/js7_joc_linux.${JS_RELEASE}.tar.gz \
        --http-port=${JS_HTTP_PORT} \
        --https-port=${JS_HTTPS_PORT} \
        --dbms-init=off \
        --dbms-config=/usr/local/src/resources/hibernate.cfg.xml \
        --keystore=/usr/local/src/resources/https-keystore.p12 \
        --keystore-password=jobscheduler \
        --truststore=/usr/local/src/resources/https-truststore.p12 \
        --truststore-password=jobscheduler \
        --user=jobscheduler \
        --title="JOC Cockpit" \
        --as-user \
        --java-options="${JS_JAVA_OPTIONS}" \
        --make-dirs && \
    rm -f /usr/local/src/js7_joc_linux.${JS_RELEASE}.tar.gz

# BUILD IMAGE

FROM alpine:3.20 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=${JS_USER_ID:-1001}
ARG JS_HTTP_PORT=${JS_HTTP_PORT:-4446}
ARG JS_HTTPS_PORT=${JS_HTTPS_PORT:-4443}
ARG JS_JAVA_OPTIONS=${JS_JAVA_OPTIONS}

# JS7 user id, ports and Java options
ENV RUN_JS_USER_ID=${RUN_JS_USER_ID:-1001}
ENV RUN_JS_HTTP_PORT=${RUN_JS_HTTP_PORT:-$JS_HTTP_PORT}
ENV RUN_JS_HTTPS_PORT=${RUN_JS_HTTPS_PORT:-$JS_HTTPS_PORT}
ENV RUN_JS_JAVA_OPTIONS=${RUN_JS_JAVA_OPTIONS:-$JS_JAVA_OPTIONS}

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

# copy entrypoint script
COPY entrypoint.sh /usr/local/bin/

# install process tools, net tools, bash, openjdk
# add jobscheduler user account and group
# for JDK < 12, /dev/random does not provide sufficient entropy, see https://kb.sos-berlin.com/x/lIM3
RUN apk upgrade --available && apk add \
    --no-cache \
    --repository=http://dl-cdn.alpinelinux.org/alpine/edge/main \
    procps \
    net-tools \
    bash \
    su-exec \
    shadow \
    git \
    openjdk17-jre && \
    sed -i 's/securerandom.source=file:\/dev\/random/securerandom.source=file:\/dev\/urandom/g' /usr/lib/jvm/java-17-openjdk/conf/security/java.security && \
    sed -i 's/jdk.tls.disabledAlgorithms=SSLv3, RC4, DES, MD5withRSA, DH keySize < 1024, \\/jdk.tls.disabledAlgorithms=SSLv3, RC4, DES, MD5withRSA, DH keySize < 1024, TLSv1, TLSv1.1, \\/g' /usr/lib/jvm/java-17-openjdk/conf/security/java.security && \
    adduser -u ${JS_USER_ID} -G root --disabled-password --home /home/jobscheduler --shell /bin/bash jobscheduler && \
    mkdir -p /var/log/sos-berlin.com/js7/joc && \
    chown -R jobscheduler:root /opt/sos-berlin.com /var/sos-berlin.com /var/log/sos-berlin.com/js7/joc && \
    chmod -R g=u /etc/passwd /opt/sos-berlin.com /var/sos-berlin.com /var/log/sos-berlin.com/js7/joc && \
    chmod +x /usr/local/bin/entrypoint.sh

# START

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

Explanation:

The Dockerfile 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 - 13: Defaults for the user id running the JOC Cockpit inside the container as well as HTTP and HTTPS ports are provided. These values can be overwritten by providing the relevant build arguments.
Line 16 - 17: Users can either download the JOC Cockpit tarball directly from the SOS web site or store the tarball with the build directory and copy from this location.
Line 20: The tarball integrity is tested.
Line 23 - 24: The JOC Cockpit Installer Script is downloaded or copied, see JS7 - Unix Shell Installation Script - js7_install_joc.sh
Line 27: The config folder available in the build directory is copied to the appropriate config folder in the image. This can be useful for creating an image with individual settings in configuration files, see the JS7 - JOC Cockpit Configuration Items article for more information.
- The hibernate.cfg.xml specifies the database connection. This file is not used at build-time. However, it is provided as a sample for run-time configuration. You will find details in the JS7 - Database article.
- The default https-keystore.p12 and https-truststore.p12 files are copied that would hold the private key and certificate required for server authentication with HTTPS. By default empty keystore and truststore files are used that users would add their private keys and certificates to at run-time.
Line 32: A recent Java release is added to the pre-image.
Line 33: The jobscheduler account is created.
Line 35 - 52: The JOC Cockpit Installer Script is executed with arguments performing installation for the jobscheduler account. For use of arguments see headless installation of the JOC Cockpit, see JS7 - JOC Cockpit Installation On Premises. In fact a JOC Cockpit installation is performed when building the image
Line 72 - 75: 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 81: The entrypoint.sh script is copied from the build directory to the image, see next chapter.
Line 82: The jetty.sh script is copied from the build directory to the image. This script ships with the Jetty Servlet Container and for on premises installations is available from the JETTY_HOME/bin directory. Users might have to adjust the script to strip off commands that require root permissions, for example chown, and commands that might not be applicable to their container environment, for example use of su.
Line 87 - 93: The image OS is updated and additional packages are installed (ps, netstat, bash, git).
Line 94: The most recent Java 11 package available with Alpine is applied. JOC Cockpit 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 on top of this. For details see Which Java versions is JobScheduler available for?
Line 95: Java releases might 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 96: Users might want to disable certain TLS protocol versions or algorithms by applying changes to the Java security file.
Line 97 - 100: The jobscheduler account is created and is assigned the user id handed over by the relevant build argument. This suggests that the account running the JOC Cockpit inside the container and the account that starts the container are assigned the same user id. This allows the account running the container to access any files created by the JOC Cockpit in mounted volumes with identical permissions.
- Consider that the account is assigned the root group. For environments in which the entrypoint script is executed with an arbitrary non-root user id this allows access to files created by the JOC Cockpit provided to any accounts that are assigned the root group.
- Accordingly any files owned by the jobscheduler account are made accessible to the root group with similar user permissions. Read access to /etc/passwd can be required in such environments.
- For details see JS7 - Running Containers for User Accounts.
Line 105: The entrypoint script is executed and is dynamically parameterized from environment variables which are forwarded when starting the container.

Entrypoint Script

Download: entrypoint.sh

The following entrypoint script is used to start JOC Cockpit containers.

JOC Cockpit Entrypoint Script

#!/bin/bash

JETTY_BASE="/var/sos-berlin.com/js7/joc"

update_joc_properties() {
  # update joc.properties file: ${JETTY_BASE}/resources/joc/joc.properties
  rc=$(grep -E '^cluster_id' "${JETTY_BASE}"/resources/joc/joc.properties)
  if [ -z "${rc}" ]
  then
    echo ".. update_joc_properties [INFO] updating cluster_id in ${JETTY_BASE}/resources/joc/joc.properties"
    printf "cluster_id = joc\n" >> "${JETTY_BASE}"/resources/joc/joc.properties
  fi

  rc=$(grep -E '^ordering' "${JETTY_BASE}"/resources/joc/joc.properties)
  if [ -z "${rc}" ]
  then
    echo ".. update_joc_properties [INFO] updating ordering in ${JETTY_BASE}/resources/joc/joc.properties"
    printf "ordering=%1\n" "$(shuf -i 0-99 -n 1)" >> "${JETTY_BASE}"/resources/joc/joc.properties
  fi
}

startini_to_startd() {
  # convert once ${JETTY_BASE}/resources/joc/start.ini to ${JETTY_BASE}/resources/joc/start.d
  if [ -d "${JETTY_BASE}"/start.d ]; then
    if [ -f "${JETTY_BASE}"/resources/joc/start.ini ] && [ -d "${JETTY_BASE}"/resources/joc/start.d ]; then
      echo ".. startini_to_startd [INFO] converting start.ini to start.d ini files"
      for file in "${JETTY_BASE}"/resources/joc/start.d/*.ini; do
        module="$(basename "$file" | cut -d. -f1)"
        echo ".... [INFO] processing module ${module}"
        while read -r line; do
          modulevariablekeyprefix="$(echo "${line}" | cut -d. -f1,2)"
          if [ "${modulevariablekeyprefix}" = "jetty.${module}" ] || [ "${modulevariablekeyprefix}" = "jetty.${module}Context" ]; then
            modulevariablekey="$(echo "${line}" | cut -d= -f1 | sed 's/\s*$//g')"
            echo "....  startini_to_startd [INFO] ${line}"
            sed -i "s;.*${modulevariablekey}\s*=.*;${line};g" "${file}"
          fi
        done < "${JETTY_BASE}"/resources/joc/start.ini
      done
      mv -f "${JETTY_BASE}"/resources/joc/start.ini "${JETTY_BASE}"/resources/joc/start.in~
    fi
  fi
}

add_start_configuration() {
  # overwrite ini files in start.d if available from config folder
  if [ -d "${JETTY_BASE}"/start.d ]; then
    if [ -d "${JETTY_BASE}"/resources/joc/start.d ]; then
      for file in "${JETTY_BASE}"/resources/joc/start.d/*.ini; do
        echo ".. add_start_configuration [INFO] copying ${file} -> ${JETTY_BASE}/start.d/"
        cp -f "$file" "${JETTY_BASE}"/start.d/
      done
    fi
  fi
}

add_jdbc_and_license() {
  # if license folder not empty then copy js7-license.jar to Jetty's class path
  if [ -d "${JETTY_BASE}"/resources/joc/license ]; then
    if [ -f "${JETTY_BASE}"/resources/joc/lib/js7-license.jar ]; then
      echo ".. add_jdbc_and_license [INFO] copying ${JETTY_BASE}/resources/joc/lib/js7-license.jar -> ${JETTY_BASE}/lib/ext/joc/"
      cp -f "${JETTY_BASE}"/resources/joc/lib/js7-license.jar "${JETTY_BASE}"/lib/ext/joc/
    fi
  fi

  # if JDBC driver added then copy to Jetty's class path and move exiting JDBC drivers back to avoid conflicts
  if [ -d "${JETTY_BASE}"/resources/joc/lib ]; then
    if [ -n "$(ls "${JETTY_BASE}"/resources/joc/lib/*.jar 2>/dev/null | grep -v "js7-license.jar")" ]; then
      for file in "${JETTY_BASE}"/lib/ext/joc/*.jar; do
        if [ "$(basename "$file")" != "js7-license.jar" ]; then
          echo ".. add_jdbc_and_license [INFO] moving ${file} -> ${JETTY_BASE}/resources/joc/lib/$(basename "$file")~"
          mv -f "$file" "${JETTY_BASE}"/resources/joc/lib/"$(basename "$file")"~
        fi
      done

      for file in "${JETTY_BASE}"/resources/joc/lib/*.jar; do
        echo ".. add_jdbc_and_license [INFO] copying ${file} -> ${JETTY_BASE}/lib/ext/joc/"
        cp -f "$file" "${JETTY_BASE}"/lib/ext/joc/
      done
    fi
  fi
}

add_custom_logo() {
  # if image folder in the configuration directory is not empty then images are copied to the installation directory
  if [ -d "${JETTY_BASE}"/resources/joc/image ];then
    mkdir -p  "${JETTY_BASE}"/webapps/root/ext/images
    echo ".. add_custom_logo [INFO] copying ${JETTY_BASE}/resources/joc/image/* -> ${JETTY_BASE}/webapps/root/ext/images/"
    cp "${JETTY_BASE}"/resources/joc/image/* "${JETTY_BASE}"/webapps/root/ext/images/
  fi
}

patch_api() {
  if [ ! -d "${JETTY_BASE}"/resources/joc/patches ]; then
    echo ".. patch_api [INFO] API patch directory not found: ${JETTY_BASE}/resources/joc/patches"
    return
  fi

  if [ ! -d "${JETTY_BASE}"/webapps/joc/WEB-INF/classes ]; then
    echo ".. patch_api [WARN] JOC Cockpit API sub-directory not found: ${JETTY_BASE}/webapps/joc/WEB-INF/classes" 
    return
  fi

  jarfiles=$(ls "${JETTY_BASE}"/resources/joc/patches/js7_joc.*-PATCH.API-*.jar 2>/dev/null)
  if [ -n "${jarfiles}" ]; then
    cd "${JETTY_BASE}"/webapps/joc/WEB-INF/classes > /dev/null || return
    for jarfile in "${JETTY_BASE}"/resources/joc/patches/js7_joc.*-PATCH.API-*.jar; do
      echo ".. patch_api [INFO] extracting ${jarfile} -> ${JETTY_BASE}/webapps/joc/WEB-INF/classes"
      unzip -o "${jarfile}" || return
      # rm -f "${jarfile}" || return
    done
    cd - > /dev/null || return
  else
    echo ".. patch_api [INFO] no API patches available from .jar files in directory: ${JETTY_BASE}/resources/joc/patches"
  fi

  tarballs=$(ls "${JETTY_BASE}"/resources/joc/patches/js7_joc.*-PATCH.API-*.tar.gz 2>/dev/null)
  if [ -n "${tarballs}" ]; then
    if [ "$(echo "${tarball}" | wc -l)" -eq 1 ]; then
      cd "${JETTY_BASE}"/webapps/joc/WEB-INF/classes > /dev/null || return
      for tarfile in "${JETTY_BASE}"/resources/joc/patches/js7_joc.*-PATCH.API-*.tar.gz; do
        echo ".. patch_api [INFO] extracting ${tarfile} -> ${JETTY_BASE}/webapps/joc/WEB-INF/classes"
        tar -xpozf "${tarfile}" || return
        # rm -f  "${tarfile}" || return

        for jarfile in "${JETTY_BASE}"/resources/joc/patches/js7_joc.*-PATCH.API-*.jar; do
          echo ".. patch_api [INFO] extracting ${jarfile} -> ${JETTY_BASE}/webapps/joc/WEB-INF/classes"
          unzip -o "${jarfile}"
          # rm -f  "${jarfile}" || return
        done

        # rm -f "${tarfile}" || return
      done
      cd - > /dev/null || return
    else
      echo ".. patch_api [WARN]: more than one tarball found for API patches. Please drop previous patch tarballs and use the latest API patch tarball only as it includes previous patches."
    fi
  else
     echo ".. patch_api [INFO] no API patches available from .tar.gz files in directory: ${JETTY_BASE}/resources/joc/patches"
  fi
}

patch_gui() {
  if [ ! -d "${JETTY_BASE}"/resources/joc/patches ]; then
    echo ".. patch_gui [INFO] GUI patch directory not found: ${JETTY_BASE}/resources/joc/patches"
    return
  fi

  if [ ! -d "${JETTY_BASE}"/webapps/joc ]; then
    echo ".. patch_gui [WARN] JOC Cockpit GUI sub-directory not found: ${JETTY_BASE}/webapps/joc"
    return
  fi

  tarball=$(ls "${JETTY_BASE}"/resources/joc/patches/js7_joc.*-PATCH.GUI-*.tar.gz 2>/dev/null)
  if [ -n "${tarball}" ]; then
    if [ "$(echo "${tarball}" | wc -l)" -eq 1 ]; then
      echo ".. patch_gui [INFO] applying GUI patch tarball: ${tarball}"
      cd "${JETTY_BASE}"/webapps/joc > /dev/null || return
      find "${JETTY_BASE}"/webapps/joc -maxdepth 1 -type f -delete || return

      if [ -d "${JETTY_BASE}"/webapps/joc/assets ]; then
        rm -fr "${JETTY_BASE}"/webapps/joc/assets || return
      fi

      if [ -d "${JETTY_BASE}"/webapps/joc/styles ]; then
        rm -fr "${JETTY_BASE}"/webapps/joc/styles || return
      fi

      tar -xpozf "${tarball}" || return
      cd - > /dev/null || return
    else
      echo ".. patch_gui [WARN]: more than one tarball found for GUI patches. Please drop previous patch tarballs and use the latest GUI patch tarball only as it includes previous patches."
    fi
  else
    echo ".. patch_gui [INFO] no GUI patches available from .tar.gz files in directory: ${JETTY_BASE}/resources/joc/patches"
  fi
}


# create JOC Cockpit start script
echo '#!/bin/sh' > "${JETTY_BASE}"/start-joc.sh
echo 'trap "/opt/sos-berlin.com/js7/joc/jetty/bin/jetty.sh stop; exit" TERM INT' >> "${JETTY_BASE}"/start-joc.sh
echo '/opt/sos-berlin.com/js7/joc/jetty/bin/jetty.sh start && tail -f /dev/null &'   >> "${JETTY_BASE}"/start-joc.sh
echo 'wait' >> "${JETTY_BASE}"/start-joc.sh
chmod +x "${JETTY_BASE}"/start-joc.sh

echo "JS7 entrypoint script: updating image"

# update joc.properties file
update_joc_properties

# start.ini_to_startd
add_start_configuration

# copy custom logo
add_custom_logo


if [ -n "${RUN_JS_HTTP_PORT}" ]
then
  if [ -f "${JETTY_BASE}"/start.d/http.in~ ] && [ ! -f "${JETTY_BASE}"/start.d/http.ini ]; then
    # enable http access in start.d directory
    mv "${JETTY_BASE}"/start.d/http.in~ "${JETTY_BASE}"/start.d/http.ini
  fi
  if [ -f "${JETTY_BASE}"/start.d/http.ini ]; then
    # set port for http access in start.d directory
    sed -i "s/.*jetty.http.port\s*=.*/jetty.http.port=$RUN_JS_HTTP_PORT/g" "${JETTY_BASE}"/start.d/http.ini
  fi
else
  if [ -f "${JETTY_BASE}"/start.d/http.ini ]; then
    # disable http access in start.d directory
    mv -f "${JETTY_BASE}"/start.d/http.ini "${JETTY_BASE}"/start.d/http.in~
  fi
fi

if [ -n "${RUN_JS_HTTPS_PORT}" ]
then
  if [ -f "${JETTY_BASE}"/start.d/https.in~ ] && [ ! -f "${JETTY_BASE}"/start.d/https.ini ]; then
    # enable https access in start.d directory
    mv "${JETTY_BASE}"/start.d/https.in~ "${JETTY_BASE}"/start.d/https.ini
  fi
  if [ -f "${JETTY_BASE}"/start.d/ssl.in~ ] && [ ! -f "${JETTY_BASE}"/start.d/ssl.ini ]; then
    # enable https access in start.d directory
    mv "${JETTY_BASE}"/start.d/ssl.in~ "${JETTY_BASE}"/start.d/ssl.ini
  fi
  if [ -f "${JETTY_BASE}"/start.d/ssl.ini ]; then
    # set port for https access in start.d directory
    sed -i "s/.*jetty.ssl.port\s*=.*/jetty.ssl.port=${RUN_JS_HTTPS_PORT}/g" "${JETTY_BASE}"/start.d/ssl.ini
  fi
else
  if [ -f "${JETTY_BASE}"/start.d/https.ini ]; then
    # disable https access in start.d directory
    mv -f "${JETTY_BASE}"/start.d/https.ini "${JETTY_BASE}"/start.d/https.in~
  fi
  if [ -f "${JETTY_BASE}"/start.d/ssl.ini ]; then
    # disable https access in start.d directory
    mv -f "${JETTY_BASE}"/start.d/ssl.ini "${JETTY_BASE}"/start.d/ssl.in~
  fi
fi

if [ -n "${RUN_JS_JAVA_OPTIONS}" ]
then
  export JAVA_OPTIONS="${JAVA_OPTIONS} ${RUN_JS_JAVA_OPTIONS}"
fi

JS_USER_ID=$(echo "${RUN_JS_USER_ID}" | cut -d ':' -f 1)
JS_GROUP_ID=$(echo "${RUN_JS_USER_ID}" | cut -d ':' -f 2)

JS_USER_ID=${JS_USER_ID:-$(id -u)}
JS_GROUP_ID=${JS_GROUP_ID:-$(id -g)}

BUILD_GROUP_ID=$(grep 'jobscheduler' /etc/group | head -1 | cut -d ':' -f 3)
BUILD_USER_ID=$(grep 'jobscheduler' /etc/passwd | head -1 | cut -d ':' -f 3)

add_jdbc_and_license
patch_api
patch_gui

if [ "$(id -u)" = "0" ]
then
  if [ ! "${BUILD_USER_ID}" = "${JS_USER_ID}" ]
  then
    echo "JS7 entrypoint script: switching ownership of image user id '${BUILD_USER_ID}' -> '${JS_USER_ID}'"
    usermod -u "${JS_USER_ID}" jobscheduler
    find /var/sos-berlin.com/ -user "${BUILD_USER_ID}" -exec chown -h jobscheduler {} \;
    find /var/log/sos-berlin.com/ -user "${BUILD_USER_ID}" -exec chown -h jobscheduler {} \;
  fi

  if [ ! "${BUILD_GROUP_ID}" = "${JS_GROUP_ID}" ]
  then
    if grep -q "${JS_GROUP_ID}" /etc/group
    then
      groupmod -g "${JS_GROUP_ID}" jobscheduler
    else
      addgroup -g "${JS_GROUP_ID}" -S jobscheduler
    fi

    echo "JS7 entrypoint script: switching ownership of image group id '${BUILD_GROUP_ID}' -> '${JS_GROUP_ID}'"
    find /var/sos-berlin.com/ -group "${BUILD_GROUP_ID}" -exec chgrp -h jobscheduler {} \;
    find /var/log/sos-berlin.com/ -group "${BUILD_GROUP_ID}" -exec chgrp -h jobscheduler {} \;
  fi

  echo "JS7 entrypoint script: switching to user account 'jobscheduler' to run start script"
  echo "JS7 entrypoint script: starting JOC Cockpit: exec su-exec ${JS_USER_ID}:${JS_GROUP_ID} /opt/sos-berlin.com/js7/joc/jetty/bin/jetty.sh start"
  exec su-exec "${JS_USER_ID}":0 "${JETTY_BASE}"/start-joc.sh
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)' using 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 '$(id -u)', image user id '${BUILD_USER_ID}' -> '${JS_USER_ID}', image group id '${BUILD_GROUP_ID}' -> '${JS_GROUP_ID}'"
  fi

  echo "JS7 entrypoint script: starting JOC Cockpit: exec sh -c /opt/sos-berlin.com/js7/joc/jetty/bin/jetty.sh start"
  exec sh -c "${JETTY_BASE}/start-joc.sh"
fi

Explanation:

Note that the entrypoint script runs the JOC Cockpit start script using exec sh -c. This is required to run the JOC Cockpit inside the current process that is assigned PID 1. A later docker stop <container> command will send a SIGTERM signal to the process with PID 1 only. If JOC Cockpit were started directly as a shell script without use of exec then a new process with a different PID would be created. This means that the docker stop command would not normally terminate JOC Cockpit, but would abort JOC Cockpit when killing the container. This can cause delays for fail-over between clustered JOC Cockpit containers.

Build Script

The build script offers a number of options to parameterize the Dockerfile:

Build Script for JOC Cockpit Image

#!/bin/sh

set -e

SCRIPT_HOME=$(dirname "$0")
SCRIPT_HOME="`cd "${SCRIPT_HOME}" >/dev/null && pwd`"
SCRIPT_FOLDER="`basename $(dirname "$SCRIPT_HOME")`"


# ----- modify default settings -----

JS_RELEASE="2.5.0"
JS_REPOSITORY="sosberlin/js7"
JS_IMAGE="$(basename "${SCRIPT_HOME}")-${JS_RELEASE//\./-}"

JS_USER_ID="$UID"

JS_HTTP_PORT="4446"
JS_HTTPS_PORT=

JS_JAVA_OPTIONS="-Xmx128m"
JS_BUILD_ARGS=

# ----- modify default settings -----


for option in "$@"
do
  case "$option" in
         --release=*)      JS_RELEASE=`echo "$option" | sed 's/--release=//'`
                           ;;
         --repository=*)   JS_REPOSITORY=`echo "$option" | sed 's/--repository=//'`
                           ;;
         --image=*)        JS_IMAGE=`echo "$option" | sed 's/--image=//'`
                           ;;
         --user-id=*)      JS_USER_ID=`echo "$option" | sed 's/--user-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 "$option" | sed 's/--java-options=//'`
                           ;;
         --build-args=*)   JS_BUILD_ARGS=`echo "$option" | sed 's/--build-args=//'`
                           ;;
         *)                echo "unknown argument: $option"
                           exit 1
                           ;;
  esac
done

set -x

docker build --no-cache --rm \
      --tag=$JS_REPOSITORY:$JS_IMAGE \
      --file=$SCRIPT_HOME/build/Dockerfile \
      --build-arg="JS_RELEASE=$JS_RELEASE" \
      --build-arg="JS_RELEASE_MAJOR=$(echo $JS_RELEASE | cut -d . -f 1,2)" \
      --build-arg="JS_USER_ID=$JS_USER_ID" \
      --build-arg="JS_HTTP_PORT=$JS_HTTP_PORT" \
      --build-arg="JS_HTTPS_PORT=$JS_HTTPS_PORT" \
      --build-arg="JS_JAVA_OPTIONS=$JS_JAVA_OPTIONS" \
      $JS_BUILD_ARGS $SCRIPT_HOME/build

set +x

Explanation:

Line 12 - 22: Default values are specified that are used if no command line arguments are provided. This includes values for:
- the release number: adjust this value to a current release of JS7.
- the repository which by default is sosberlin:js7.
- the image name is determined from the current folder name and the release number.
- the user id is by default the id of the user running the build script.
- the HTTP port and HTTPS port: if the relevant port is not specified then the JOC Cockpit will not listen to that port for the protocol in question. You can, for example, disable the HTTP protocol by specifying an empty value. The default ports should be fine as they are mapped by the run script to outside ports on the container's host. However, you can modify ports as you like.
- Java options: typically you would specify default values for, for example, Java memory consumption. The Java options can be overwritten by the run script when starting the container. However, you might want to create your own image with adjusted default values.
Line 27 - 50: The above options can be overwritten by command line arguments like this:
Running the Build Script with Arguments
```
./build.sh --http-port=14445 --https-port=14443 --java-options="-Xmx1G"
```
Line 54 - 63: The effective docker build command is executed with arguments. The Dockerfile is assumed to be located with the build sub-directory of the current directory.

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Introduction

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JS7 - JOC Cockpit Build of Container Image

Introduction

Build Environment

Dockerfile

Entrypoint Script

Build Script