2.基础知识：
1、每个保留关键字（指令）都是必须是----大写字母！！！！！ 2、执行从上到下顺序执行 3、#表示注释 4、每一个指令都会创建提交一个新的镜像层，并提交
- dockerfile是面向开发的，我们以后要发布项目，做镜像，就需要编写dockerfile文件，这个文件十分简单！
- Docker镜像逐渐成为了企业交付的标准，必须要掌握!!!
步骤：开发，部署，运维…缺一不可
- DockerFile：构建文件，定义了一切的步骤，源代码
- DockerImages：
通过DockerFile构建生成的镜像，最终发布和运行的产品 - Docker容器：
容器就是镜像运行起来提供服务的
3.DockerFile 指令
我们可以通过这些指令进行自定义基础镜像
FROM # 基础镜像，一切从这里开始 MAINTAINER # 镜像是谁写的，姓名+邮箱 RUN # 镜像构建的时候需要运行的命令 ADD # 步骤：往里面加东西：tomcat镜像，这个tomcat压缩包，添加内容 WORKDIR # 镜像的工作目录 VOLUME # 挂载的目录 EXPOSE # 暴露端口配置 CMD # 指定容器运行时的shell命令，只有最后一个生效，可被替代 ENTRYPOINT # 指定容器运行时的shell命令，可以追加命令 ONBUILD # 当构建一个被继承DockerFile这个时候就会运行ONBUILD的指令，触发指令 COPY # 类似ADD，将我们文件拷贝到镜像中,但不会自动解压 ENV # 构建的时候设置环境变量
4.实战测试
Docker Hub中99%镜像都是从这个
FROM scratch ADD centos-7-x86_64-docker.tar.xz / LABEL \ org.label-schema.schema-version="1.0" \ org.label-schema.name="CentOS Base Image" \ org.label-schema.vendor="CentOS" \ org.label-schema.license="GPLv2" \ org.label-schema.build-date="20201113" \ org.opencontainers.image.title="CentOS Base Image" \ org.opencontainers.image.vendor="CentOS" \ org.opencontainers.image.licenses="GPL-2.0-only" \ org.opencontainers.image.created="2020-11-13 00:00:00+00:00" CMD ["/bin/bash"]
(1). 创建一个自己的centos
1. 编写一个DockerFile配置文件 FROM centos:7 #来源于哪? MAINTAINER jsxs<2261203961@qq.com> #作者信息 ENV MYPATH /usr/local #设置默认pwd路径 WORKDIR $MYPATH #工作目录 RUN yum -y install vim #安装vim镜像 RUN yum -y install net-tools #安装工具镜像 EXPOSE 80 #暴漏端口80 CMD echo $MYPATH #输出文件 CMD echo "-----end---" CMD /bin/bash #运行中执行这个命令 ------------------------------- 2. 构建镜像 docker build -f mysockerfile -t jsxs-centos:1.0 . 3.测试运行 docker run -it --name jsxs-centos01 jsxs-centos:1.0 4. 研究怎么做的 docker history 0ab761aa5334 IMAGE CREATED CREATED BY SIZE COMMENT 0ab761aa5334 11 minutes ago CMD ["/bin/sh" "-c" "/bin/bash"] 0B buildkit.dockerfile.v0 <missing> 11 minutes ago CMD ["/bin/sh" "-c" "echo \"-----end---\""] 0B buildkit.dockerfile.v0 <missing> 11 minutes ago CMD ["/bin/sh" "-c" "echo $MYPATH"] 0B buildkit.dockerfile.v0 <missing> 11 minutes ago EXPOSE map[80/tcp:{}] 0B buildkit.dockerfile.v0 <missing> 11 minutes ago RUN /bin/sh -c yum -y install net-tools # bu… 25MB buildkit.dockerfile.v0 <missing> 11 minutes ago RUN /bin/sh -c yum -y install vim # buildkit 259MB buildkit.dockerfile.v0 <missing> 11 minutes ago WORKDIR / 0B buildkit.dockerfile.v0 <missing> 11 minutes ago ENV YPATH=/usr/local 0B buildkit.dockerfile.v0 <missing> 11 minutes ago MAINTAINER jsxs<2261203961@qq.com> 0B buildkit.dockerfile.v0 <missing> 18 months ago /bin/sh -c #(nop) CMD ["/bin/bash"] 0B <missing> 18 months ago /bin/sh -c #(nop) LABEL org.label-schema.sc… 0B <missing> 18 months ago /bin/sh -c #(nop) ADD file:b3ebbe8bd304723d4… 204MB
构建镜像
我们发现我们自定义的镜像增加了好多命令
5.CMD 与 ENTRYPOINT 区别
(1).CMD
覆盖
CMD
------------------------ [root@Jsxs dockerfile]# vim dockerfile-cmd-test #编写文件 FROM centos:7 CMD ["ls","-a"] ------- # 构建文件 -f 打包的文件 -t 打包后的镜像标题 [root@Jsxs dockerfile]# docker build -f dockerfile-cmd-test -t cmdtest . [+] Building 0.4s (5/5) FINISHED => [internal] load .dockerignore 0.1s => => transferring context: 2B 0.0s => [internal] load build definition from dockerfile-cmd-test 0.1s => => transferring dockerfile: 76B 0.0s => [internal] load metadata for docker.io/library/centos:7 0.4s => CACHED [1/1] FROM docker.io/library/centos:7@sha256:9d4bcbbb213dfd745b58be38b13b996ebb5ac315fe75711bd618426a630e0987 0.0s => exporting to image 0.0s => => exporting layers 0.0s => => writing image sha256:d53776618e7ca21294bf0d76a1042fa5976f2b0992727c1122ede2900cd8ba93 0.0s => => naming to docker.io/library/cmdtest 0.0s ----- # 创建容器并执行 [root@Jsxs dockerfile]# docker run -it --name testcmd1 cmdtest . .. .dockerenv anaconda-post.log bin dev etc home lib lib64 media mnt opt proc root run sbin srv sys tmp usr var
我们像追加一个命令 -l "ls -al"显示全部数据，-l;不是命令所以报错 [root@Jsxs dockerfile]# docker images REPOSITORY TAG IMAGE ID CREATED SIZE jsxs-centos 1.0 0ab761aa5334 31 minutes ago 488MB nginx latest 605c77e624dd 14 months ago 141MB tomcat 9.0 b8e65a4d736d 15 months ago 680MB mysql 5.7 c20987f18b13 15 months ago 448MB cmdtest latest d53776618e7c 18 months ago 204MB centos latest 5d0da3dc9764 18 months ago 231MB centos-test 1.0 0282d836c4f5 18 months ago 231MB portainer/portainer latest 580c0e4e98b0 2 years ago 79.1MB [root@Jsxs dockerfile]# docker run d53776618e7c -l docker: Error response from daemon: failed to create shim task: OCI runtime create failed: runc create failed: unable to start container process: exec: "-l": executable file not found in $PATH: unknown. 我们需要编写一个完整的命令进行替换- [root@Jsxs ~]# docker run d53776618e7c ls -al total 64 drwxr-xr-x 1 root root 4096 Mar 22 14:38 . drwxr-xr-x 1 root root 4096 Mar 22 14:38 .. -rwxr-xr-x 1 root root 0 Mar 22 14:38 .dockerenv -rw-r--r-- 1 root root 12114 Nov 13 2020 anaconda-post.log lrwxrwxrwx 1 root root 7 Nov 13 2020 bin -> usr/bin drwxr-xr-x 5 root root 340 Mar 22 14:38 dev drwxr-xr-x 1 root root 4096 Mar 22 14:38 etc drwxr-xr-x 2 root root 4096 Apr 11 2018 home lrwxrwxrwx 1 root root 7 Nov 13 2020 lib -> usr/lib lrwxrwxrwx 1 root root 9 Nov 13 2020 lib64 -> usr/lib64 drwxr-xr-x 2 root root 4096 Apr 11 2018 media drwxr-xr-x 2 root root 4096 Apr 11 2018 mnt drwxr-xr-x 2 root root 4096 Apr 11 2018 opt dr-xr-xr-x 225 root root 0 Mar 22 14:38 proc dr-xr-x--- 2 root root 4096 Nov 13 2020 root drwxr-xr-x 11 root root 4096 Nov 13 2020 run lrwxrwxrwx 1 root root 8 Nov 13 2020 sbin -> usr/sbin drwxr-xr-x 2 root root 4096 Apr 11 2018 srv dr-xr-xr-x 13 root root 0 Mar 22 14:38 sys drwxrwxrwt 7 root root 4096 Nov 13 2020 tmp drwxr-xr-x 13 root root 4096 Nov 13 2020 usr drwxr-xr-x 18 root root 4096 Nov 13 2020 var
(2).ENTRYPOINT
追加
vim dockerfile-cmd-entrypoint FROM centos:7 ENTRYPOINT ["ls","-a"] [root@Jsxs dockerfile]# docker build -f dockerfile-cmd-entrypoint -t entrypointtest . [+] Building 15.4s (5/5) FINISHED => [internal] load build definition from dockerfile-cmd-entrypoint 0.0s => => transferring dockerfile: 89B 0.0s => [internal] load .dockerignore 0.0s => => transferring context: 2B 0.0s => [internal] load metadata for docker.io/library/centos:7 15.4s => CACHED [1/1] FROM docker.io/library/centos:7@sha256:9d4bcbbb213dfd745b58be38b13b996ebb5ac315fe75711bd618426a630e0987 0.0s => exporting to image 0.0s => => exporting layers 0.0s => => writing image sha256:dbcf4f99ed1cde79a9a4034b78ca79e0829f3e83bc9830a34065a1918f0dbcfa 0.0s => => naming to docker.io/library/entrypointtest 0.0s [root@Jsxs dockerfile]# docker run "docker run" requires at least 1 argument. See 'docker run --help'. Usage: docker run [OPTIONS] IMAGE [COMMAND] [ARG...] Create and run a new container from an image [root@Jsxs dockerfile]# [root@Jsxs dockerfile]# docker run entrypointtest . .. .dockerenv anaconda-post.log bin dev etc home lib lib64 media mnt opt proc root run sbin srv sys tmp usr var # 拼接 追加 [root@Jsxs dockerfile]# docker run entrypointtest -l total 64 drwxr-xr-x 1 root root 4096 Mar 22 14:46 . drwxr-xr-x 1 root root 4096 Mar 22 14:46 .. -rwxr-xr-x 1 root root 0 Mar 22 14:46 .dockerenv -rw-r--r-- 1 root root 12114 Nov 13 2020 anaconda-post.log lrwxrwxrwx 1 root root 7 Nov 13 2020 bin -> usr/bin drwxr-xr-x 5 root root 340 Mar 22 14:46 dev drwxr-xr-x 1 root root 4096 Mar 22 14:46 etc drwxr-xr-x 2 root root 4096 Apr 11 2018 home lrwxrwxrwx 1 root root 7 Nov 13 2020 lib -> usr/lib lrwxrwxrwx 1 root root 9 Nov 13 2020 lib64 -> usr/lib64 drwxr-xr-x 2 root root 4096 Apr 11 2018 media drwxr-xr-x 2 root root 4096 Apr 11 2018 mnt drwxr-xr-x 2 root root 4096 Apr 11 2018 opt dr-xr-xr-x 223 root root 0 Mar 22 14:46 proc dr-xr-x--- 2 root root 4096 Nov 13 2020 root drwxr-xr-x 11 root root 4096 Nov 13 2020 run lrwxrwxrwx 1 root root 8 Nov 13 2020 sbin -> usr/sbin drwxr-xr-x 2 root root 4096 Apr 11 2018 srv dr-xr-xr-x 13 root root 0 Mar 22 14:46 sys drwxrwxrwt 7 root root 4096 Nov 13 2020 tmp drwxr-xr-x 13 root root 4096 Nov 13 2020 usr drwxr-xr-x 18 root root 4096 Nov 13 2020 var
6.实战Tomcat镜像
(1).准备 tomcat 与 jdk 安装包
(2).编写Dockerfile文件
Dockerfile 是官方名字，我们启动的时候就会自动寻找这个名字。
[root@Jsxs jsxs]# touch readme.md [root@Jsxs jsxs]# vim Dockerfile FROM centos:7 MAINTAINER jsxs<2261203961@qq.com> COPY readme.md /usr/local/readme.md ADD jdk-8u202-linux-x64.tar.gz /usr/local ADD apache-tomcat-9.0.73.tar.gz /usr/local RUN yum -y install vim ENV MYPATH /usr/local WORKDIR $MYPATH ENV JAVA_HOME /usr/local/jdk1.8.0_202 ENV CLASSPATH $JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar ENV CATALINA_HOME /usr/local/apache-tomcat-9.0.73 ENV CATALINA_BASH /usr/local/apache-tomcat-9.0.73 ENV PATH $PATH:$JAVA_HOME/bin:$CATALINA_HOME/lib:$CATALINA_HOME/bin EXPOSE 8080 CMD /usr/local/apache-tomcat-9.0.73/bin/startup.sh && tail -F /usr/local/apache-tomcat-9.0.73/logs/catalina.out
(3).构建镜像
docker build -f Dockerfile -t diytomcat . [+] Building 53.8s (11/11) FINISHED => [internal] load .dockerignore 0.1s => => transferring context: 2B 0.0s => [internal] load build definition from Dockerfile 0.2s => => transferring dockerfile: 665B 0.0s => [internal] load metadata for docker.io/library/centos:7 15.4s => [internal] load build context 4.0s => => transferring context: 190.09MB 3.3s => CACHED [1/6] FROM docker.io/library/centos:7@sha256:9d4bcbbb213dfd745b58be38b13b996ebb5ac315fe75711bd618426a630e0987 0.0s => [2/6] COPY readme.md /usr/local/readme.md 0.2s => [3/6] ADD jdk-8u202-linux-x64.rpm /usr/local 3.6s => [4/6] ADD apache-tomcat-9.0.73.tar.gz /usr/local 1.1s => [5/6] RUN yum -y install vim 20.3s => [6/6] WORKDIR /usr/local 0.2s => exporting to image 8.1s => => exporting layers 7.8s => => writing image sha256:0e1f35086fef111eaeda3d551188b84844a446a49bd6d24ef4319b16f06458ce 0.0s => => naming to docker.io/library/diytomcat
(4).创建容器并开启
docker run -d -p 9090:8080 --name jsxstomcat -v /home/jsxs/test:/usr/local/apache-tomcat-9.0.73/webapps/test -v /home/jsxs/testlog/:/usr/local/apache-tomcat-9.0.73/logs diytomcat ---------------- # 解释，第一个挂载是将webapps下的test映射到本地tomcat下的test -v /home/eric/build/tomcat/test:/usr/local/apache-tomcat-9.0.8/webapps/test # 解释，第二个挂载是将apache-tomcat-9.0.8下的日志映射到本地tomcat下的tomcatlogs -v /home/eric/build/tomcat/tomcatlogs/:/usr/local/apache-tomcat-9.0.8/logs ----------------------
(5).开启容器
[root@Jsxs ~]# docker exec -it 52300f8c0167b2d23726c7acb135081462a1a31cf31d1756654176f6f43c7f32 /bin/bash [root@52300f8c0167 local]# pwd /usr/local [root@52300f8c0167 local]# ls apache-tomcat-9.0.73 bin etc games include jdk1.8.0_202 lib lib64 libexec readme.md sbin share src
外网访问测试成功!!
(6).发布项目
（由于做了卷挂载，我们直接在本地编写项目就可以发布了）
[root@Jsxs test]# mkdir WEB-INF [root@Jsxs test]# ls WEB-INF [root@Jsxs test]# cd WEB-INF/ [root@Jsxs WEB-INF]# vim web.xml [root@Jsxs WEB-INF]# cat web.xml <?xml version="1.0" encoding="UTF-8"?> <web-app version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"> </web-app> [root@Jsxs WEB-INF]# cd .. [root@Jsxs test]# vim index.jsp [root@Jsxs test]# cat index.jsp <%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>hello. xiaofan</title> </head> <body> Hello World!<br/> <% System.out.println("-----my test web logs------"); %> </body> </html> ----------------------------------------------------------------------------------- # 这是web.xml内容 <?xml version="1.0" encoding="UTF-8"?> <web-app version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"> </web-app> ------------------------------------------------------------------------------------- ------------------------------------------------------------------------------------- # 这是index.jsp内容 <%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>hello. xiaofan</title> </head> <body> Hello World!<br/> <% System.out.println("-----my test web logs------"); %> </body> </html> ------------------------------------------------------------------
ls -tail -f #可以动态查看列表
发现：项目部署成功， 可以直接访问ok！
我们以后开发的步骤：需要掌握Dockerfile的编写！ 我们之后的一切都是使用docker进行来发布运行的！
