Translate docker run into subcomponents

Question

I have this docker run command:

docker run --rm --name=gitleaks \
   -v "/keys/ssh/values:/root/.ssh"  \
   zricethezav/gitleaks  \
   --ssh-key='bucket' \
   --repo "$line"

I tranlated it to this:

  docker create zricethezav/gitleaks --name=gitleaks
  docker cp /keys/ssh/values gitleaks:/root/.ssh
  docker start gitleaks  --ssh-key='bucket' --repo "$line"

but it gives me this error:

Error: No such container:path: gitleaks:/root
unknown flag: --ssh-key

Does anybody know where I went wrong? Ultimately I am calling docker run from within a running container and am having trouble sharing files, so trying to get docker cp to work.

Answer 1

Issue is with your first and second command syntax.

docker create zricethezav/gitleaks --name=gitleaks 

--name should be before image name, otherwise docker create will interpret it as COMMAND argument instead of OPTIONS flag.

 docker start gitleaks --ssh-key='bucket' --repo "$line"

I understand you want to run the image with parameters --ssh-key and --repo, however it's not possible with docker start command. If you want to have these parameters passed to the process run by the image, you should pas these parameters to docker create or docker run command after the image name.

So you should do:

# Mind the --name before the image name
docker create --name=gitleaks zricethezav/gitleaks --ssh-key='bucket' --repo "$line"
docker cp /keys/ssh/values gitleaks:/root/.ssh
docker start gitleaks

Explanations for docker create:

docker create usage is:

docker create [OPTIONS] IMAGE [COMMAND] [ARG...]

Where OPTIONS flags should be specified before IMAGE, and everything after IMAGE will be interpreted as COMMAND and ARG....

When you are running

docker create zricethezav/gitleaks --name=gitleaks

You are in fact passing --name=gitleaks as COMMAND which will override default image command (the one tipycally provided by CMD in Dockerfile), where you probably want to pass it as OPTIONS. For example, if you run:

docker create alpine --name=foobar
docker create --name=foobar alpine

docker ps -a output will look like:

IMAGE        COMMAND              NAMES
alpine       "/bin/sh"            foobar
alpine       "--name=foobar"      quirky_varahamihira

If you want to pass both OPTIONS and COMMAND, you must specify OPTIONS before the image name and COMMAND after the image name.