Bug in get_docker_configuration_file_args() causes false positives

[brsolomon-deloitte]

It appears that get_docker_configuration_file_args is not behaving as intended, and causing some false-positive WARN results for release v1.5.0.

This function breaks down to the following, which I've reproduced below:

grep "$OPTION" "$CONFIG_FILE" | sed 's/.*://g' | tr -d '" ',

Simplest reproduction:

$ echo '{"userland-proxy": false, "icc": false, "disable-legacy-registry": true, "live-restore": true}' | sed 's/.*://g'
 true}

More detail:

$ cat /etc/docker/daemon.json
{"userland-proxy": false, "icc": false, "disable-legacy-registry": true, "live-restore": true}
$ grep 'userland-proxy' /etc/docker/daemon.json | sed 's/.*://g' | tr -d '" ',
true}

$ cd /tmp
$ cat << EOF > test-daemon.json
> {
>   "userland-proxy": false,
>   "icc": false,
>   "disable-legacy-registry": true,
>   "live-restore": true
> }
> EOF
$ grep 'userland-proxy' test-daemon.json | sed 's/.*://g' | tr -d '" ',
false

$ grep -F PRETTY_NAME /etc/os-release
PRETTY_NAME="Red Hat Enterprise Linux Server 7.9 (Maipo)"

$ sed --version
sed (GNU sed) 4.2.2
Copyright (C) 2012 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

Written by Jay Fenlason, Tom Lord, Ken Pizzini,
and Paolo Bonzini.
GNU sed home page: <http://www.gnu.org/software/sed/>.
General help using GNU software: <http://www.gnu.org/gethelp/>.
E-mail bug reports to: <bug-sed@gnu.org>.
Be sure to include the word ``sed'' somewhere in the ``Subject:'' field.

$ tr --version
tr (GNU coreutils) 8.22
Copyright (C) 2013 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

Written by Jim Meyering.

So, perhaps the function logic there assumes that daemon.json is prettified (multi-line) rather than minified.

[brsolomon-deloitte]

Verified this further - simply by prettifying daemon.json with jq, the checks are then reported as PASSED.

[brsolomon-deloitte]

Suggestion: make it easy and use (require) jq inside of get_docker_configuration_file_args - or at least attempt to use jq if it is present, then fall back to the existing method.

[konstruktoid]

Thanks for reporting this and submitting a PR @brsolomon-deloitte
I've added a couple of comments to the PR.