使用DockerFile在Alpine容器中安装python3定制镜像

1. 在一个空白目录中，建立一个文本文件，并命名为 Dockerfile：

$ mkdir test
$ cd test
$ touch Dockerfile

2. 准备好 Dockerfile :

FROM alpine:latest

RUN apk update \
    && apk add python3 \
    && rm -rf /var/cache/apk/*

3. 在 Dockerfile 文件所在目录执行：

$ docker build . -t develop:1.0
[+] Building 333.5s (6/6) FINISHED                                                                                                               
 => [internal] load build definition from Dockerfile                                                                                              
 => => transferring dockerfile: 191B                                                                                                             
 => [internal] load metadata for docker.io/library/alpine:latest                                                                                
 => [internal] load .dockerignore                                                                                                                
 => => transferring context: 2B                                                                                                                 
 => [1/3] FROM docker.io/library/alpine:latest                                                                                                  
 => [2/3] RUN apk update     && apk add python3     && rm -rf /var/cache/apk/*                                                                  
 => exporting to image                                                                                                                       
 => => exporting layers                                                                                                                     
 => => writing image sha256:9ce5ebfba6495ccd8301c7251f53c358a04e6c106ef5cf78d4be8402db6b70fb                                                
 => => naming to docker.io/library/develop:1.0

注意，docker build 命令最后有一个 .。. 表示当前目录

4. 查看结果：

$ docker images
REPOSITORY   TAG       IMAGE ID       CREATED         SIZE
develop      1.0       9ce5ebfba649   1 hours ago     48.4MB