摘要：上一篇容器化开发环境数据库连接和迁移分享了关于如何给容器中的应用创建数据库连接，接下来将分享一下如何将数据库从应用容器中分离出来。
上一篇容器化开发环境 - 数据库连接和迁移分享了关于如何给容器中的应用创建数据库连接，接下来将分享一下如何将数据库从应用容器中分离出来。
为什么要进行分离？当应用和数据库在同一个容器中运行时，也就意味着，应用和数据库的生命周期捆绑在了一起，应用和数据库的运行就会出现相互干扰现象，应用的异常将有可能导致容器的停止，同时也将导致数据库的关闭。更主要的原因是，很多时候需要多个容器中的应用连接一个数据库，为了保证容器之间的运行相互独立，相互不影响，就有必要将数据库隔离在独立的容器中运行，让数据库和容器独处二人世界，同时保证数据库的生命周期不在受其它应用影响。
Setup Codebase
clone hello-dockerie repo
$ git clone https://github.com/aikin/hello-dockerize.git
Separate MySQL Dockerfile
在dockerize目录下创建mysql/Dockerfle
修改mysql/Dockerfile，配置安装MySQL脚本：
FROM ubuntu:14.04
RUN apt-get update
# === Install Mysql ===
RUN groupadd -r mysql && useradd -r -g mysql mysql
RUN mkdir /docker-entrypoint-initdb.d
ENV MYSQL_MAJOR 5.7
ENV MYSQL_VERSION 5.7.11-1ubuntu14.04
# gpg: key 5072E1F5: public key "MySQL Release Engineering " imported
RUN apt-key adv --keyserver ha.pool.sks-keyservers.net --recv-keys A4A9406876FCBD3C456770C88C718D3B5072E1F5
RUN echo "deb http://repo.mysql.com/apt/ubuntu/ trusty mysql-${MYSQL_MAJOR}" > /etc/apt/sources.list.d/mysql.list
# the "/var/lib/mysql" stuff here is because the mysql-server postinst doesn"t have an explicit way to disable the mysql_install_db codepath besides having a database already "configured" (ie, stuff in /var/lib/mysql/mysql)
# also, we set debconf keys to make APT a little quieter
RUN {
echo mysql-community-server mysql-community-server/data-dir select "";
echo mysql-community-server mysql-community-server/root-pass password "";
echo mysql-community-server mysql-community-server/re-root-pass password "";
echo mysql-community-server mysql-community-server/remove-test-db select false;
} | debconf-set-selections
RUN apt-get update && apt-get install -y mysql-server="${MYSQL_VERSION}"
RUN rm -rf /var/lib/apt/lists/*
RUN rm -rf /var/lib/mysql && mkdir -p /var/lib/mysql
# comment out a few problematic configuration values
# don"t reverse lookup hostnames, they are usually another container
RUN sed -Ei "s/^(bind-address|log)/#&/" /etc/mysql/my.cnf
&& echo "skip-host-cache
skip-name-resolve" | awk "{ print } $1 == "[mysqld]" && c == 0 { c = 1; system("cat") }" /etc/mysql/my.cnf > /tmp/my.cnf
&& mv /tmp/my.cnf /etc/mysql/my.cnf
VOLUME /var/lib/mysql
COPY docker-entrypoint.sh /usr/local/bin/
RUN chmod +x /usr/local/bin/docker-entrypoint.sh
RUN ln -s usr/local/bin/docker-entrypoint.sh /entrypoint.sh # backwards compat
ENTRYPOINT ["docker-entrypoint.sh"]
EXPOSE 3306
CMD ["mysqld"]
修改dockerize/Dockerfile，移除安装MySQL的配置：
FROM ubuntu:14.04
RUN apt-get update
ENV VERSION 8
ENV UPDATE 66
ENV BUILD 17
ENV JAVA_HOME /usr/lib/jvm/java-${VERSION}-oracle
ENV JRE_HOME ${JAVA_HOME}/jre
RUN apt-get install ca-certificates curl
gcc libc6-dev libssl-dev make
-y --no-install-recommends
RUN curl --silent --location --retry 3 --cacert /etc/ssl/certs/GeoTrust_Global_CA.pem
--header "Cookie: oraclelicense=accept-securebackup-cookie;"
http://download.oracle.com/otn-pub/java/jdk/"${VERSION}"u"${UPDATE}"-b"${BUILD}"/server-jre-"${VERSION}"u"${UPDATE}"-linux-x64.tar.gz
| tar xz -C /tmp
RUN mkdir -p /usr/lib/jvm && mv /tmp/jdk1.${VERSION}.0_${UPDATE} "${JAVA_HOME}"
RUN apt-get install -y openssl
RUN apt-get remove --purge --auto-remove -y
gcc
libc6-dev
libssl-dev
make
RUN apt-get autoclean && apt-get --purge -y autoremove
RUN rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
RUN update-alternatives --install "/usr/bin/java" "java" "${JRE_HOME}/bin/java" 1 &&
update-alternatives --install "/usr/bin/javac" "javac" "${JAVA_HOME}/bin/javac" 1 &&
update-alternatives --set java "${JRE_HOME}/bin/java" &&
update-alternatives --set javac "${JAVA_HOME}/bin/javac"
WORKDIR /hello-dockerize
EXPOSE 8080
EXPOSE 5005
CMD ["bash"]
将dockerize/docker-entrypoint.sh移动到dockerize/mysql目录下
Startup
修改docker-compose.yml:
web:
build: ./dockerize
environment:
- LANG=C.UTF-8
- TERM=xterm
- DEBUG=true
links:
- mysql:mysql
ports:
- "8080:8080"
- "5005:5005"
volumes:
- .:/hello-dockerize
mysql:
build: ./dockerize/mysql
env_file: ./dockerize/dev.env
ports:
- "3306:3306"
volumes:
- /var/lib/mysql:/var/lib/mysql
启动容器：
$ docker-compose up
查看容器
$ docker-compse ps
######
Name Command State Ports
---------------------------------------------------------------------------------------------------------------
hellodockerize_mysql_1 docker-entrypoint.sh mysqld Up 0.0.0.0:3306->3306/tcp
hellodockerize_web_run_1 bash Up 0.0.0.0:5005->5005/tcp, 0.0.0.0:8080->8080/tcp
######
执行 migrate 命令:
root@6485a7a48988:/hello-dockerize# ./gradlew flywayClean flywayInit flywayMigrate
Check Migrate Result On Intellij IDEA
查看 User 表
原文链接
文章版权归作者所有，未经允许请勿转载,若此文章存在违规行为，您可以联系管理员删除。
转载请注明本文地址：https://www.ucloud.cn/yun/26760.html
