import -c 'CMD...' behavior does not match

[vbatts]

/kind bug

Description

comparing the behavior of docker-1.13.1 with podman 1.2.0, the podman import -c 'CMD..' ... behaviour does not match back.
podman is expecting 'CMD=/usr/bin/farts' (the '='), and fails with 'CMD /usr/bin/farts' (the ' '), and fails with brackets 'CMD ["/usr/bin/farts"]'.

[vbatts@knob] {master} ~$ podman import -c 'CMD ["/usr/bin/farts"]' ./farts.tar vbatts/farts
Error: invalid argument "CMD [\"/usr/bin/farts\"]" for "-c, --change" flag: parse error on line 1, column 5: bare " in non-quoted-field
[vbatts@knob] {master} ~$ podman import -c 'CMD /usr/bin/farts' ./farts.tar vbatts/farts
Error: error adding config changes to image "./farts.tar": no value given for instruction "CMD /usr/bin/farts"
[vbatts@knob] {master} ~$ podman import -c 'CMD=/usr/bin/farts' ./farts.tar vbatts/farts
Getting image source signatures
Copying blob 7a230c035746 done
Copying config 66c42e9891 done
Writing manifest to image destination
Storing signatures
66c42e989172c9294213dda7ec4917d285ce6f646f0972b3e4eb7605a65b9dc1

whereas docker-1.13.1 supports ' ' and brackets, but fails with '='.

[vbatts@beats] {master} ~$ docker import -c 'CMD=/usr/bin/farts' ./farts.tar vbatts/farts
Error response from daemon: cmd=/usr/bin/farts is not a valid change command
[vbatts@beats] {master} ~$ docker import -c 'CMD ["/usr/bin/farts"]' ./farts.tar vbatts/farts
sha256:19b84065571402b7844b8866d4cd9d7babf86d350da23338c64ea96446f36b56
[vbatts@beats] {master} ~$ docker import -c 'CMD /usr/bin/farts' ./farts.tar vbatts/farts
sha256:7d6d0a14238fa4ce51c5138537acb95d8c20a6a9f8b54753382a301e00ba59f6

Output of podman version:

Version:            1.2.0
RemoteAPI Version:  1
Go Version:         go1.11.5
Git Commit:         3bd528e583182b4249f3e6bbd8497a8831d89950
Built:              Tue Apr  2 09:59:40 2019
OS/Arch:            linux/amd64

Package info (e.g. output of rpm -q podman or apt list podman):

podman-1.5.1-3.fc29.x86_64

[kunalkushwaha]

currently, the changes are parsed with = only. https://github.com/containers/libpod/blob/a16f63e96e9993a1e2542b6f5c85903cc4659c6e/pkg/util/utils.go#L92

need to be fixed.

[kunalkushwaha]

How about supporting all three syntax.

i.e.

--change CMD=/bin/bash

--change CMD /bin/bash

--change CMD ["/bin/bash"]

[vrothberg]

How about supporting all three syntax.

Good idea. This way we remain backward compatible 👍 @kunalkushwaha, are you interested in working on this?

[kunalkushwaha]

almost there.. shall make a PR soon.