Docker CMD exec-form for multiple command execution
DockerDockerfileDocker Problem Overview
Here is a silly example of running multiple commands via the CMD
instruction in shell-form. I would prefer to use the exec-form, but I don't know how to concatenate the instructions.
shell-form:
CMD mkdir -p ~/my/new/directory/ \
&& cd ~/my/new/directory \
&& touch new.file
exec-form:
CMD ["mkdir","-p","~/my/new/directory/"]
# What goes here?
Can someone provide the equivalent syntax in exec-form?
Docker Solutions
Solution 1 - Docker
The short answer is, you cannot chain together commands in the exec form.
&&
is a function of the shell, which is used to chain commands together. In fact, when you use this syntax in a Dockerfile, you are actually leveraging the shell functionality.
If you want to have multiple commands with the exec form, then you have do use the exec form to invoke the shell as follows...
CMD ["sh","-c","mkdir -p ~/my/new/directory/ && cd ~/my/new/directory && touch new.file"]
Solution 2 - Docker
I would argue though that these commands should be execute with at a RUN step rather than CMD.
RUN mkdir -p ~/my/new/directory/ && \
cd ~/my/new/directory && \
touch new.file