Docker学习系列七：构建jetty镜像

前言

Docker hub官方已经维护了一套比较完善的jetty镜像，但是依赖的是openjdk。所以这里只是把jdk换成之前学习系列中构建过的oracle-jdk8。

Dockerfile描述

FROM oraclejdk8
   MAINTAINER zacard <[email protected]>

   # add our user and group first to make sure their IDs get assigned consistently, regardless of whatever dependencies get added
   RUN addgroup -S jetty && adduser -D -S -H -G jetty jetty && rm -rf /etc/group- /etc/passwd- /etc/shadow-

   ENV JETTY_HOME /usr/local/jetty
   ENV PATH $JETTY_HOME/bin:$PATH
   RUN mkdir -p "$JETTY_HOME"
   WORKDIR $JETTY_HOME

   ENV JETTY_BASE /var/lib/jetty
   RUN mkdir -p "$JETTY_BASE"

   ENV JETTY_VERSION 9.3.10.v20160621
   ENV JETTY_TGZ_URL https://repo1.maven.org/maven2/org/eclipse/jetty/jetty-distribution/$JETTY_VERSION/jetty-distribution-$JETTY_VERSION.tar.gz

   # GPG Keys are personal keys of Jetty committers (see https://dev.eclipse.org/mhonarc/lists/jetty-users/msg05220.html)
   ENV JETTY_GPG_KEYS \
           # 1024D/8FB67BAC 2006-12-10 Joakim Erdfelt <[email protected]>
           B59B67FD7904984367F931800818D9D68FB67BAC \
           # 1024D/D7C58886 2010-03-09 Jesse McConnell (signing key) <[email protected]>
           5DE533CB43DAF8BC3E372283E7AE839CD7C58886

   RUN set -xe \
           # Install required packages for build time. Will be removed when build finishes.
           && apk add --no-cache --virtual .build-deps gnupg coreutils curl \

           && curl -SL "$JETTY_TGZ_URL" -o jetty.tar.gz \
           && curl -SL "$JETTY_TGZ_URL.asc" -o jetty.tar.gz.asc \
           && export GNUPGHOME="$(mktemp -d)" \
           && for key in $JETTY_GPG_KEYS; do \
                   gpg --keyserver ha.pool.sks-keyservers.net --recv-keys "$key"; done \
           && gpg --batch --verify jetty.tar.gz.asc jetty.tar.gz \
           && rm -r "$GNUPGHOME" \
           && tar -xvzf jetty.tar.gz \
           && mv jetty-distribution-$JETTY_VERSION/* ./ \
           && sed -i '/jetty-logging/d' etc/jetty.conf \
           && rm -fr demo-base javadoc \
           && rm jetty.tar.gz* \
           && rm -fr jetty-distribution-$JETTY_VERSION/ \

           # Get the list of modules in the default start.ini and build new base with those modules, then add setuid
           && cd $JETTY_BASE \
           && modules="$(grep -- ^--module= "$JETTY_HOME/start.ini" | cut -d= -f2 | paste -d, -s)" \
           && java -jar "$JETTY_HOME/start.jar" --add-to-startd="$modules,setuid" \

           # Remove installed packages and various cleanup
           && apk del .build-deps \
           && rm -fr .build-deps \
           && rm -rf /tmp/hsperfdata_root

   WORKDIR $JETTY_BASE

   ENV TMPDIR /tmp/jetty
   RUN set -xe \
           && mkdir -p "$TMPDIR" \
           && chown -R jetty:jetty "$TMPDIR" "$JETTY_BASE"

   COPY docker-entrypoint.sh /

   EXPOSE 8080
   ENTRYPOINT ["/docker-entrypoint.sh"]
   CMD ["java","-jar","/usr/local/jetty/start.jar"]

说明

这里的Dockerfile是根据官方的jetty9-alpine改写。其实也仅仅是把依赖镜像改成了自己构建的oracle-jdk8而已。

这里还依赖了一个sh文件，具体内容如下：

docker-entrypoint.sh：

#!/bin/sh

   set -e

   if [ "$1" = jetty.sh ]; then
       if ! command -v bash >/dev/null 2>&1 ; then
           cat >&2 <<- 'EOWARN'
               ********************************************************************
               ERROR: bash not found. Use of jetty.sh requires bash.
               ********************************************************************
           EOWARN
           exit 1
       fi
       cat >&2 <<- 'EOWARN'
           ********************************************************************
           WARNING: Use of jetty.sh from this image is deprecated and may
               be removed at some point in the future.

               See the documentation for guidance on extending this image:
               https://github.com/docker-library/docs/tree/master/jetty
           ********************************************************************
       EOWARN
   fi

   if ! command -v -- "$1" >/dev/null 2>&1 ; then
       set -- java -jar "$JETTY_HOME/start.jar" "$@"
   fi

   if [ -n "$TMPDIR" ] ; then
       case "$JAVA_OPTIONS" in
           *-Djava.io.tmpdir=*) ;;
           *) JAVA_OPTIONS="-Djava.io.tmpdir=$TMPDIR $JAVA_OPTIONS" ;;
       esac
   fi

   if [ "$1" = "java" -a -n "$JAVA_OPTIONS" ] ; then
       shift
       set -- java $JAVA_OPTIONS "$@"
   fi

   exec "$@"

注意：docker-entrypoint.sh要和Dockerfile同一目录，且需要设置可执行权限。

build镜像

docker buile -t jetty:9-oraclejdk8 .

测试镜像

docker run –rm jetty:9-oraclejdk8 –list-config

启动镜像

具体如何启动部署镜像，请参考官方说明文档。传送门

保存镜像

docker save -o jetty.tar jetty:9-oraclejdk8

加载镜像

docker -i jetty.tar