关于docker：如何将ARG值传递给ENTRYPOINT？

How to pass ARG value to ENTRYPOINT?

Docker 1.9允许将参数传递给dockerfile。请参阅链接：https：//docs.docker.com/engine/reference/builder/#arg

我怎样才能在ENTRYPOINT指令中传递相同的句子？

我的dockerfile有

ARG $Version=3.1
ENTRYPOINT /tmp/folder-$Version/sample.sh start

使用上面的dockerfile创建容器时出错。
请建议在ENTRYPOINT指令中指定参数的正确方法是什么？

相关讨论

像Blake Mitchell sais一样，你不能在ENTRYPOINT中使用ARG。但是，您可以将ARG用作ENV的值，这样就可以将其与ENTRYPOINT一起使用：

Dockerfile

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ARG my_arg
ENV my_env_var=$my_arg

ENTRYPOINT echo $my_env_var

并运行：

1	docker build --build-arg"my_arg=foo" ...

简短回答：你需要使用ENV

ARG和ENV都未在ENTRYPOINT或CMD中展开。 (https://docs.docker.com/engine/reference/builder/#environment-replacement)但是，因为ENV是作为环境的一部分传入的，所以它们在运行时可用，所以shell可以扩展他们。 (这意味着您不能使用ENTRYPOINT或CMD的数组形式。)

这是一个例子：

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$ cat arg/Dockerfile
FROM debian:jessie
ARG FOO=bar
ENTRYPOINT echo ${FOO:-foo}
$ sudo docker build arg
Sending build context to Docker daemon 2.048 kB
Step 1 : FROM debian:jessie
---> f50f9524513f
Step 2 : ARG FOO=bar
---> Using cache
---> 2cfdcb514b62
Step 3 : ENTRYPOINT echo ${FOO:-foo}
---> Running in 21fb9b42c10d
---> 75e5018bad83
Removing intermediate container 21fb9b42c10d
Successfully built 75e5018bad83
$ sudo docker run 75e5018bad83
foo
$ sudo docker run -e FOO=bas 75e5018bad83
bas
$ sudo docker build --build-arg FOO=bas arg
Sending build context to Docker daemon 2.048 kB
Step 1 : FROM debian:jessie
---> f50f9524513f
Step 2 : ARG FOO=bar
---> Using cache
---> 2cfdcb514b62
Step 3 : ENTRYPOINT echo ${FOO:-foo}
---> Using cache
---> 75e5018bad83
Successfully built 75e5018bad83
$ sudo docker run 75e5018bad83
foo
$ cat env/Dockerfile
FROM debian:jessie
ARG FOO=bar
ENV FOO=${FOO}
ENTRYPOINT echo ${FOO:-foo}
$ sudo docker build env
Sending build context to Docker daemon 2.048 kB
Step 1 : FROM debian:jessie
---> f50f9524513f
Step 2 : ARG FOO=bar
---> Using cache
---> 2cfdcb514b62
Step 3 : ENV FOO ${FOO}
---> Running in f157a07c1b3e
---> a5e8c5b65a17
Removing intermediate container f157a07c1b3e
Step 4 : ENTRYPOINT echo ${FOO:-foo}
---> Running in 66e9800ef403
---> 249fe326e9ce
Removing intermediate container 66e9800ef403
Successfully built 249fe326e9ce
$ sudo docker run 249fe326e9ce
bar
$ sudo docker run -e FOO=bas 249fe326e9ce
bas
$ sudo docker build --build-arg FOO=bas env
Sending build context to Docker daemon 2.048 kB
Step 1 : FROM debian:jessie
---> f50f9524513f
Step 2 : ARG FOO=bar
---> Using cache
---> 2cfdcb514b62
Step 3 : ENV FOO ${FOO}
---> Running in 6baf31684b9f
---> 8f77ad154798
Removing intermediate container 6baf31684b9f
Step 4 : ENTRYPOINT echo ${FOO:-foo}
---> Running in 892ac47cabed
---> fa97da85bf8a
Removing intermediate container 892ac47cabed
Successfully built fa97da85bf8a
$ sudo docker run fa97da85bf8a
bas
$