4、Dockerfile构建私有镜像

Dockerfile基础知识点

#第一行必须指令基于的基础镜像
From ubutu
#维护者信息
MAINTAINER heyazhou heyazhou@leconginfo.com
#给镜像添加信息。使用docker inspect可查看镜像的相关信息
LABEL <key>=<value> <key>=<value> <key>=<value> ...
#指定一个环节变量
ENV <key> <value>       # 只能设置一个变量
ENV <key>=<value> ...    # 允许一次设置多个变量
#ADD复制本地主机文件、目录或者远程文件 URLS 从 并且添加到容器指定路径中 
ADD <src>... <dest>
#COPY复制新文件或者目录从 并且添加到容器指定路径中 。用法同ADD，唯一的不同是不能指定远程文件 URLS
COPY <src>... <dest>
#RUN在镜像构建之前执行任何命令，并把执行的结果传递给下一步使用
RUN <command>
RUN ["executable", "param1", "param2"]
#VOLUME将宿主机上的目录文件挂在到对应的容器中
VOLUME ["/data"]
#ENTRYPOINT在镜像构建成功之后执行任何命令，并且不可被 docker run 提供的参数覆盖，而CMD是可以被覆盖的。
ENTRYPOINT ["executable", "param1", "param2"] 
ENTRYPOINT command param1 param2
#EXPOSE 容器在运行中对外提供的端口能力，默认是TCP协议，可以指定UDP
EXPOSE 80/tcp
#CMD在镜像构建成功之后执行任何命令
CMD ["executable","param1","param2"] 
CMD ["param1","param2"] 
CMD command param1 param2

构建镜像

编写Dockerfile文件，符合要求规范。Dockerfile文件命名为“Dockerfile”
在Dockerfile所在目录执行构建命令，sudo docker build ``-t 镜像名称:版本号`` ``.

构建初始化SQL脚本的MySQL镜像

Dockerfile内容

#基础镜像
FROM mysql:latest
#作者
MAINTAINER heyazhou <heyazhou@leconginfo.com>
#定义会被容器自动执行的目录
ENV AUTO_RUN_DIR /docker-entrypoint-initdb.d
#定义sql文件名
ENV INIT_FILE init_db.sql
#把要执行的shell文件放到/docker-entrypoint-initdb.d/目录下，容器会自动执行这个shell
COPY ./$INIT_FILE $AUTO_RUN_DIR/
#给执行文件增加可执行权限
RUN chmod a+x $AUTO_RUN_DIR/$INIT_FILE
CMD ["mysqld"]

构建镜像

sudo docker build -t init-mysql .

构建初始化SQL脚本的MySQL+Nginx镜像

Dockerfile内容

#采用构建初始化SQL脚本的MySQL镜像
FROM init-mysql:latest
LABEL maintainer="NGINX Docker Maintainers <docker-maint@nginx.com>"
ENV NGINX_VERSION 1.13.12-1~stretch
ENV NJS_VERSION   1.13.12.0.2.0-1~stretch
RUN set -x \
    && apt-get update \
    && apt-get install --no-install-recommends --no-install-suggests -y gnupg1 apt-transport-https ca-certificates \
    && \
    NGINX_GPGKEY=573BFD6B3D8FBC641079A6ABABF5BD827BD9BF62; \
    found=''; \
    for server in \
        ha.pool.sks-keyservers.net \
        hkp://keyserver.ubuntu.com:80 \
        hkp://p80.pool.sks-keyservers.net:80 \
        pgp.mit.edu \
    ; do \
        echo "Fetching GPG key $NGINX_GPGKEY from $server"; \
        apt-key adv --keyserver "$server" --keyserver-options timeout=10 --recv-keys "$NGINX_GPGKEY" && found=yes && break; \
    done; \
    test -z "$found" && echo >&2 "error: failed to fetch GPG key $NGINX_GPGKEY" && exit 1; \
    apt-get remove --purge --auto-remove -y gnupg1 && rm -rf /var/lib/apt/lists/* \
    && dpkgArch="$(dpkg --print-architecture)" \
    && nginxPackages=" \
        nginx=${NGINX_VERSION} \
        nginx-module-xslt=${NGINX_VERSION} \
        nginx-module-geoip=${NGINX_VERSION} \
        nginx-module-image-filter=${NGINX_VERSION} \
        nginx-module-njs=${NJS_VERSION} \
    " \
    && case "$dpkgArch" in \
        amd64|i386) \
# arches officialy built by upstream
            echo "deb https://nginx.org/packages/mainline/debian/ stretch nginx" >> /etc/apt/sources.list.d/nginx.list \
            && apt-get update \
            ;; \
        *) \
# we're on an architecture upstream doesn't officially build for
# let's build binaries from the published source packages
            echo "deb-src https://nginx.org/packages/mainline/debian/ stretch nginx" >> /etc/apt/sources.list.d/nginx.list \
            \
# new directory for storing sources and .deb files
            && tempDir="$(mktemp -d)" \
            && chmod 777 "$tempDir" \
# (777 to ensure APT's "_apt" user can access it too)
            \
# save list of currently-installed packages so build dependencies can be cleanly removed later
            && savedAptMark="$(apt-mark showmanual)" \
            \
# build .deb files from upstream's source packages (which are verified by apt-get)
            && apt-get update \
            && apt-get build-dep -y $nginxPackages \
            && ( \
                cd "$tempDir" \
                && DEB_BUILD_OPTIONS="nocheck parallel=$(nproc)" \
                    apt-get source --compile $nginxPackages \
            ) \
# we don't remove APT lists here because they get re-downloaded and removed later
            \
# reset apt-mark's "manual" list so that "purge --auto-remove" will remove all build dependencies
# (which is done after we install the built packages so we don't have to redownload any overlapping dependencies)
            && apt-mark showmanual | xargs apt-mark auto > /dev/null \
            && { [ -z "$savedAptMark" ] || apt-mark manual $savedAptMark; } \
            \
# create a temporary local APT repo to install from (so that dependency resolution can be handled by APT, as it should be)
            && ls -lAFh "$tempDir" \
            && ( cd "$tempDir" && dpkg-scanpackages . > Packages ) \
            && grep '^Package: ' "$tempDir/Packages" \
            && echo "deb [ trusted=yes ] file://$tempDir ./" > /etc/apt/sources.list.d/temp.list \
# work around the following APT issue by using "Acquire::GzipIndexes=false" (overriding "/etc/apt/apt.conf.d/docker-gzip-indexes")
#   Could not open file /var/lib/apt/lists/partial/_tmp_tmp.ODWljpQfkE_._Packages - open (13: Permission denied)
#   ...
#   E: Failed to fetch store:/var/lib/apt/lists/partial/_tmp_tmp.ODWljpQfkE_._Packages  Could not open file /var/lib/apt/lists/partial/_tmp_tmp.ODWljpQfkE_._Packages - open (13: Permission denied)
            && apt-get -o Acquire::GzipIndexes=false update \
            ;; \
    esac \
    \
    && apt-get install --no-install-recommends --no-install-suggests -y \
                        $nginxPackages \
                        gettext-base \
    && apt-get remove --purge --auto-remove -y apt-transport-https ca-certificates && rm -rf /var/lib/apt/lists/* /etc/apt/sources.list.d/nginx.list \
    \
# if we have leftovers from building, let's purge them (including extra, unnecessary build deps)
    && if [ -n "$tempDir" ]; then \
        apt-get purge -y --auto-remove \
        && rm -rf "$tempDir" /etc/apt/sources.list.d/temp.list; \
    fi
# forward request and error logs to docker log collector
RUN ln -sf /dev/stdout /var/log/nginx/access.log \
    && ln -sf /dev/stderr /var/log/nginx/error.log
EXPOSE 80
STOPSIGNAL SIGTERM
CMD ["nginx", "-g", "daemon off;"]
CMD ["mysqld"]

构建镜像

sudo docker build -t init-mysql-nginx .