docker - 您如何在遇到第一个错误时取消构建的 dockerfile 镜像？

Question

如果我的 dockerfile 中的 RUN 命令出错，它会继续执行下一个命令。

Answer 1

您确定该命令真的返回错误吗？以下 Dockerfile 未到达 echo foo:

FROM alpine
RUN false
RUN echo foo

它只是得到:

# docker build .
Sending build context to Docker daemon 3.072 kB
Step 0 : FROM alpine
 ---> 0a3b5ba3277d
Step 1 : RUN false
 ---> Running in 22485c5e763c
The command '/bin/sh -c false' returned a non-zero code: 1

要检查你的命令是否真的失败了，你可以尝试这样的事情:

FROM alpine
RUN false || echo failed
RUN echo foo

这让我明白了:

# docker build .
Sending build context to Docker daemon 3.072 kB
Step 0 : FROM alpine
 ---> 0a3b5ba3277d
Step 1 : RUN false || echo failed
 ---> Running in 674f09ae7530
failed
 ---> 232fd66c5729
Removing intermediate container 674f09ae7530
Step 2 : RUN echo foo
 ---> Running in c7b541fdb15c
foo
 ---> dd1bece67e71
Removing intermediate container c7b541fdb15c
Successfully built dd1bece67e71