使用Dockerfile構建自己的tomcat映象
阿新 • • 發佈:2020-08-16
dockerfile 是用來構建docker映象的檔案!命令引數指令碼!
構建步驟:
- 編寫一個dockerfile 檔案
- docker build 構建成一個映象
- docker run 執行映象
- docker push 釋出映象(DockerHub、阿里雲映象倉庫)
# 以contes為例 檢視 dockerhub 上 contes 的 dockerfile 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="20200809" \ org.opencontainers.image.title="CentOS Base Image" \ org.opencontainers.image.vendor="CentOS" \ org.opencontainers.image.licenses="GPL-2.0-only" \ org.opencontainers.image.created="2020-08-09 00:00:00+01:00" CMD ["/bin/bash"]
DockerFile構建過程
基礎知識:
- 每個保留關鍵字(指令)都必須是大寫字母
- 執行順序從上到下順序執行
- 表示註釋
- 每個指令都會建立提交一個新的映象層,並提交
dockerfile是面向開發的,我們以後要釋出專案,做映象,就需要編寫dockerfile檔案,這個檔案十分簡單!
Docker映象逐漸成為企業交付的標準!
DockerFile:構建映象,定義了一切的步驟,原始碼;
DockerImages:通過DockerFile構建生成的一個映象,這個映象就是我們最終釋出和執行的產品!
Docker容器:容器就是映象執行起來提供服務!
DockerFile的指令
FROM # 基礎映象 MAINTAINER # 映象是誰寫的 姓名 + 郵箱 RUN # 映象構建的時候需要執行的命令 ADD # 步驟 eg:tomcat映象---》放入tomcat的壓縮包!新增內容 WORKDIR # 映象的工作目錄 VOLUME # 掛載的目錄位置 EXPOST # 暴露埠配置 CMD # 指定這個容器啟動的時候要執行的命令,只有最後一個會生效,可被替代 ENTRYPOINT # 指定這個容器啟動的時候要執行的命令,可以追加命令 ONBUILD # 當構建一個被繼承的 DockerFile ,這個時候就會執行 ONBUILD 的指令,觸發指令 COPY # 類似ADD,將我們的檔案拷貝到映象中 ENV # 構建的時候設定環境變數
實戰測試
Docker Hub 中 99% 的映象都是從 FROM scratch 這個基礎映象過來的 ,然後配置我們需要的軟體和配置來進行構建
建立一個自己的centos
# 1、編寫DockerFile的檔案 FROM centos # 作者資訊 MAINTAINER yinxiaodong<[email protected]> # 配置環境變數 ENV MYPATH /user/local # 指定映象的工作目錄 WORKDIR $MYPATH RUN yum install -y vim RUN yum install -y net-tools # 暴露80埠 EXPOSE 80 CMD echo $MYPATH CMD echo "---------end--------" CMD /bin/bash # 2、通過檔案構建映象 # 命令 docker build -f dockerfile檔案路徑 -t 映象名:版本號 . [root@localhost dockerfile]# docker build -f mydockerfile-centos -t mycentos:0.1 . Sending build context to Docker daemon 2.048kB Step 1/9 : FROM centos ---> 0d120b6ccaa8 Step 2/9 : MAINTAINER yinxiaodong<[email protected]> ---> Running in f79b12ffb083 Removing intermediate container f79b12ffb083 ---> 8ee53d3f7a65 Step 3/9 : ENV MYPATH /user/local ---> Running in 659a2c96d5f7 Removing intermediate container 659a2c96d5f7 ---> 59ab131ef44c Step 4/9 : WORKDIR $MYPATH ---> Running in 0b4b8f9c65bb Removing intermediate container 0b4b8f9c65bb ---> 408b06671488 Step 5/9 : RUN yum install -y net-tools ---> Running in 151f81148a87 CentOS-8 - AppStream 118 kB/s | 5.8 MB 00:50 CentOS-8 - Base 218 kB/s | 2.2 MB 00:10 CentOS-8 - Extras 1.8 kB/s | 7.3 kB 00:04 Dependencies resolved. ================================================================================ Package Architecture Version Repository Size ================================================================================ Installing: net-tools x86_64 2.0-0.51.20160912git.el8 BaseOS 323 k Transaction Summary ================================================================================ Install 1 Package Total download size: 323 k Installed size: 1.0 M Downloading Packages: net-tools-2.0-0.51.20160912git.el8.x86_64.rpm 219 kB/s | 323 kB 00:01 -------------------------------------------------------------------------------- Total 66 kB/s | 323 kB 00:04 warning: /var/cache/dnf/BaseOS-f6a80ba95cf937f2/packages/net-tools-2.0-0.51.20160912git.el8.x86_64.rpm: Header V3 RSA/SHA256 Signature, key ID 8483c65d: NOKEY CentOS-8 - Base 162 kB/s | 1.6 kB 00:00 Importing GPG key 0x8483C65D: Userid : "CentOS (CentOS Official Signing Key) <[email protected]>" Fingerprint: 99DB 70FA E1D7 CE22 7FB6 4882 05B5 55B3 8483 C65D From : /etc/pki/rpm-gpg/RPM-GPG-KEY-centosofficial Key imported successfully Running transaction check Transaction check succeeded. Running transaction test Transaction test succeeded. Running transaction Preparing : 1/1 Installing : net-tools-2.0-0.51.20160912git.el8.x86_64 1/1 Running scriptlet: net-tools-2.0-0.51.20160912git.el8.x86_64 1/1 Verifying : net-tools-2.0-0.51.20160912git.el8.x86_64 1/1 Installed: net-tools-2.0-0.51.20160912git.el8.x86_64 Complete! Removing intermediate container 151f81148a87 ---> c0a0546c9b2a Step 6/9 : EXPOSE 80 ---> Running in 42000936515d Removing intermediate container 42000936515d ---> fe68114ecf3f Step 7/9 : CMD echo $MYPATH ---> Running in c393fc53a354 Removing intermediate container c393fc53a354 ---> a6924276bf90 Step 8/9 : CMD echo "---------end--------" ---> Running in 5994de56f0a1 Removing intermediate container 5994de56f0a1 ---> a8ba0ebb3770 Step 9/9 : CMD /bin/bash ---> Running in d1fa2d436363 Removing intermediate container d1fa2d436363 ---> 41bb76be4884 Successfully built 41bb76be4884 Successfully tagged mycentos:0.1 [root@localhost dockerfile]# docker images REPOSITORY TAG IMAGE ID CREATED SIZE mycentos 0.1 41bb76be4884 7 seconds ago 246MB centos 1.0 d840628c30a9 6 hours ago 215MB centos latest 0d120b6ccaa8 2 days ago 215MB # 啟動 mycentos 使用 ifconfig 命令檢視ip資訊 [root@localhost dockerfile]# docker run -it mycentos:0.1 [root@494c2bc72263 local]# ifconfig eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 172.17.0.3 netmask 255.255.0.0 broadcast 172.17.255.255 ether 02:42:ac:11:00:03 txqueuelen 0 (Ethernet) RX packets 6 bytes 516 (516.0 B) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 0 bytes 0 (0.0 B) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536 inet 127.0.0.1 netmask 255.0.0.0 loop txqueuelen 1000 (Local Loopback) RX packets 0 bytes 0 (0.0 B) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 0 bytes 0 (0.0 B) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 # 檢視所在目錄 /user/local 正是我們在dockerfile中指定的目錄 [root@494c2bc72263 local]# pwd /user/local
檢視映象的構建歷史記錄
# 命令 docker history 映象id
[root@localhost ~]# docker history 41bb76be4884
IMAGE CREATED CREATED BY SIZE COMMENT
41bb76be4884 16 minutes ago /bin/sh -c #(nop) CMD ["/bin/sh" "-c" "/bin… 0B
a8ba0ebb3770 16 minutes ago /bin/sh -c #(nop) CMD ["/bin/sh" "-c" "echo… 0B
a6924276bf90 16 minutes ago /bin/sh -c #(nop) CMD ["/bin/sh" "-c" "echo… 0B
fe68114ecf3f 16 minutes ago /bin/sh -c #(nop) EXPOSE 80 0B
c0a0546c9b2a 16 minutes ago /bin/sh -c yum install -y net-tools 31.3MB
408b06671488 17 minutes ago /bin/sh -c #(nop) WORKDIR /user/local 0B
59ab131ef44c 17 minutes ago /bin/sh -c #(nop) ENV MYPATH=/user/local 0B
8ee53d3f7a65 17 minutes ago /bin/sh -c #(nop) MAINTAINER yinxiaodong<m1… 0B
0d120b6ccaa8 2 days ago /bin/sh -c #(nop) CMD ["/bin/bash"] 0B
<missing> 2 days ago /bin/sh -c #(nop) LABEL org.label-schema.sc… 0B
<missing> 2 days ago /bin/sh -c #(nop) ADD file:538afc0c5c964ce0d… 215MB
我們平時拿到一個映象,可以研究一下它是怎麼做的---->docker history 映象id
CMD 和 ENTRYPOINT 的區別
CMD 和 ENTRYPOINT 的區別
CMD # 指定這個容器啟動的時候要執行的命令,只有最後一個會生效,可被替代
ENTRYPOINT # 指定這個容器啟動的時候要執行的命令,可以追加命令
# 測試 CMD
# 編寫DockerFile的檔案
[root@localhost dockerfile]# cat dockerfile-cmd-test
FROM centos
CMD ["ls","-a"]
# 根據 DockerFile 構建映象
[root@localhost dockerfile]# docker build -f dockerfile-cmd-test -t testcmd:0.1 .
Sending build context to Docker daemon 3.072kB
Step 1/2 : FROM centos
---> 0d120b6ccaa8
Step 2/2 : CMD ["ls","-a"]
---> Running in b3f8ba72222b
Removing intermediate container b3f8ba72222b
---> 561e47f88730
Successfully built 561e47f88730
Successfully tagged testcmd:0.1 # 構建成功
# 檢視映象
[root@localhost dockerfile]# docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
testcmd 0.1 561e47f88730 6 seconds ago 215MB
centos latest 0d120b6ccaa8 2 days ago 215MB
# 啟動映象 發現ls -a命令生效
[root@localhost dockerfile]# docker run -it testcmd:0.1
. .dockerenv dev home lib64 media opt root sbin sys usr
.. bin etc lib lost+found mnt proc run srv tmp var
# 啟動命令中 追加一個 -l, 我們期望的是 ls -a -l,但是 報錯,這裡將 ls -a 替換成了 -l,最終的命令是 -l 所以報錯。
[root@localhost dockerfile]# docker run -it 561e47f88730 -l
docker: Error response from daemon: OCI runtime create failed: container_linux.go:349: starting container process caused "exec: \"-l\": executable file not found in $PATH": unknown.
# 將啟動命令替換成 docker run -it testcmd:0.1 ls -al, 成功列印詳細資訊;
[root@localhost dockerfile]# docker run -it testcmd:0.1 ls -al
total 0
drwxr-xr-x. 1 root root 6 Aug 13 08:20 .
drwxr-xr-x. 1 root root 6 Aug 13 08:20 ..
-rwxr-xr-x. 1 root root 0 Aug 13 08:20 .dockerenv
lrwxrwxrwx. 1 root root 7 May 11 2019 bin -> usr/bin
drwxr-xr-x. 5 root root 360 Aug 13 08:20 dev
drwxr-xr-x. 1 root root 66 Aug 13 08:20 etc
drwxr-xr-x. 2 root root 6 May 11 2019 home
lrwxrwxrwx. 1 root root 7 May 11 2019 lib -> usr/lib
lrwxrwxrwx. 1 root root 9 May 11 2019 lib64 -> usr/lib64
drwx------. 2 root root 6 Aug 9 21:40 lost+found
drwxr-xr-x. 2 root root 6 May 11 2019 media
drwxr-xr-x. 2 root root 6 May 11 2019 mnt
drwxr-xr-x. 2 root root 6 May 11 2019 opt
dr-xr-xr-x. 123 root root 0 Aug 13 08:20 proc
dr-xr-x---. 2 root root 162 Aug 9 21:40 root
drwxr-xr-x. 11 root root 163 Aug 9 21:40 run
lrwxrwxrwx. 1 root root 8 May 11 2019 sbin -> usr/sbin
drwxr-xr-x. 2 root root 6 May 11 2019 srv
dr-xr-xr-x. 13 root root 0 Aug 11 09:58 sys
drwxrwxrwt. 7 root root 145 Aug 9 21:40 tmp
drwxr-xr-x. 12 root root 144 Aug 9 21:40 usr
drwxr-xr-x. 20 root root 262 Aug 9 21:40 var
# 測試二:現在我們把 DockerFile 中 CMD 替換成 ENTRYPOINT 後重新構建,執行 看看結果
[root@localhost dockerfile]# cat dockerfile-cmd-test
FROM centos
ENTRYPOINT ["ls","-a"]
# 重新構建映象
[root@localhost dockerfile]# docker build -f dockerfile-cmd-test -t testcmd:0.2 .
Sending build context to Docker daemon 3.072kB
Step 1/2 : FROM centos
---> 0d120b6ccaa8
Step 2/2 : ENTRYPOINT ["ls","-a"]
---> Running in c634ca09fabe
Removing intermediate container c634ca09fabe
---> 52d295395f08
Successfully built 52d295395f08
Successfully tagged testcmd:0.2
# 檢視映象
[root@localhost dockerfile]# docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
testcmd 0.2 52d295395f08 7 seconds ago 215MB
testcmd 0.1 561e47f88730 12 minutes ago 215MB
centos latest 0d120b6ccaa8 2 days ago 215MB
# 執行testcmd:0.2映象 並追加 -l ,發現 打印出了詳細資訊
[root@localhost dockerfile]# docker run -it testcmd:0.2 -l
total 0
drwxr-xr-x. 1 root root 6 Aug 13 08:17 .
drwxr-xr-x. 1 root root 6 Aug 13 08:17 ..
-rwxr-xr-x. 1 root root 0 Aug 13 08:17 .dockerenv
lrwxrwxrwx. 1 root root 7 May 11 2019 bin -> usr/bin
drwxr-xr-x. 5 root root 360 Aug 13 08:17 dev
drwxr-xr-x. 1 root root 66 Aug 13 08:17 etc
drwxr-xr-x. 2 root root 6 May 11 2019 home
lrwxrwxrwx. 1 root root 7 May 11 2019 lib -> usr/lib
lrwxrwxrwx. 1 root root 9 May 11 2019 lib64 -> usr/lib64
drwx------. 2 root root 6 Aug 9 21:40 lost+found
drwxr-xr-x. 2 root root 6 May 11 2019 media
drwxr-xr-x. 2 root root 6 May 11 2019 mnt
drwxr-xr-x. 2 root root 6 May 11 2019 opt
dr-xr-xr-x. 121 root root 0 Aug 13 08:17 proc
dr-xr-x---. 2 root root 162 Aug 9 21:40 root
drwxr-xr-x. 11 root root 163 Aug 9 21:40 run
lrwxrwxrwx. 1 root root 8 May 11 2019 sbin -> usr/sbin
drwxr-xr-x. 2 root root 6 May 11 2019 srv
dr-xr-xr-x. 13 root root 0 Aug 11 09:58 sys
drwxrwxrwt. 7 root root 145 Aug 9 21:40 tmp
drwxr-xr-x. 12 root root 144 Aug 9 21:40 usr
drwxr-xr-x. 20 root root 262 Aug 9 21:40 var
DockerFile中很多命令都十分相似,我們需要了解他的區別,最好的學習就是對比進行測試檢視效果!
實戰:Tomcat映象
1、準備映象檔案 tomcat壓縮包 jdk壓縮包
[root@localhost tomcat]# ls
apache-tomcat-8.5.43.tar.gz Dockerfile jdk-8u211-linux-x64.tar.gz read.txt
2、編寫dockerfile檔案, 官方命名Dockerfile
,build會自動尋找這個檔案,不需要 -f 指定!
# 引入基礎
FROM centos
# 作者資訊
MAINTAINER yinxiaodoong<[email protected]>
# copy檔案read.txt到容器的 /usr/local/read.txt 目錄下
COPY read.txt /usr/local/read.txt
# 新增jdk tomcat ---> 自動解壓
ADD jdk-8u211-linux-x64.tar.gz /usr/local/
ADD apache-tomcat-8.5.43.tar.gz /usr/local/
# 安裝 vim 命令
RUN yum install -y vim
# 配置 MYPATH
ENV MYPATH /usr/local/
# 指定 進入容器預設路徑 /user/local/
WORKDIR $MYPATH
# 配置jdk環境變數
ENV JAVA_HOME /usr/local/jdk1.8.0_211
ENV CLASSPATH $JAVA_HOME/lib/dt.jat:$JAVA_HOME/lib/tools.jar
# 配置tomcat環境變數
ENV CATALINA_HOME /usr/local/apache-tomcat-8.5.43
ENV CATALINA_BASH /usr/local/apache-tomcat-8.5.43
ENV PATH $PATH:$JAVA_HOME/bin:$CATALINA_HOME/lib:$CATALINA_HOME/bin
# 暴露8080埠
EXPOSE 8080
# /usr/local/tomcat/webapps#
# 啟動容器時 啟動tomcat
CMD /usr/local/apache-tomcat-8.5.43/bin/startup.sh && tail -f /usr/local/apache-tomcat-8.5.43/logs/catalina.out
# 構建tomcat映象
[root@localhost tomcat]# docker build -t mytomcat
[root@localhost tomcat]# docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
mytomcat latest a9707559afa1 8 seconds ago 693MB
centos latest 0d120b6ccaa8 4 days ago 215MB
[root@localhost tomcat]# docker run -d -p 8081:8080 --name mytomcat--01 -v /home/yinxiaodong/build/tomcat/test:/usr/local/apache-tomcat-8.5.43/webapps/test -v /home/yinxiaodong/build/tomcat/logs:/usr/local/apache-tomcat-8.5.43/logs mytomcat
釋出自己的映象
釋出到 dockerHub
- 地址 https://hub.docker.com/ 註冊自己的賬號
- 確定自己的賬號可以登入
- 在我們的伺服器上提交
[root@localhost logs]# docker login --help
Usage: docker login [OPTIONS] [SERVER]
Log in to a Docker registry.
If no server is specified, the default is defined by the daemon.
Options:
-p, --password string Password
--password-stdin Take the password from stdin
-u, --username string Username
[root@localhost logs]#
[root@localhost logs]# docker login -u xxx -p xxx
WARNING! Using --password via the CLI is insecure. Use --password-stdin.
WARNING! Your password will be stored unencrypted in /root/.docker/config.json.
Configure a credential helper to remove this warning. See
https://docs.docker.com/engine/reference/commandline/login/#credentials-store
Login Succeeded
- 登入完畢後就可以提交映象了
[root@localhost logs]# docker push xxx/mytomcat:1.0