checks: update assignment of platform URLs var

[miabbott]

This updates the script to be more ShellCheck compliant around the
assignment of the UPDATE_PLATFORM_URLS variable and the check to see
if the varible is empty. The existing functionality remains unchanged.

Thanks to @alcir for the suggested changes!

Closes: #93

[miabbott]

I haven't tested this (which got us in trouble the first time), so let's hold off on merging until we have confidence in this change.

[pcdubs]

LGTM

[alcir]

I'm not a bash expert, but instead of disable shellcheck, here

greenboot/usr/lib/greenboot/check/wanted.d/01_update_platforms_check.sh

Line 8 in 7ad3ea5

UPDATE_PLATFORM_URLS=$(grep -P -ho 'http[s]?.*' $REPOS_DIRECTORY/*)

we could actually populate the UPDATE_PLATFORM_URLS array simply in this way

UPDATE_PLATFORM_URLS=($(grep -P -ho 'http[s]?.*' $REPOS_DIRECTORY/*))

or

readarray -t UPDATE_PLATFORM_URLS < <(grep -P -ho 'http[s]?.*' $REPOS_DIRECTORY/*)

[miabbott]

I'm not a bash expert, but instead of disable shellcheck, here

greenboot/usr/lib/greenboot/check/wanted.d/01_update_platforms_check.sh

Line 8 in 7ad3ea5

UPDATE_PLATFORM_URLS=$(grep -P -ho 'http[s]?.*' $REPOS_DIRECTORY/*)

we could actually populate the UPDATE_PLATFORM_URLS array simply in this way

UPDATE_PLATFORM_URLS=($(grep -P -ho 'http[s]?.*' $REPOS_DIRECTORY/*))

or

readarray -t UPDATE_PLATFORM_URLS < <(grep -P -ho 'http[s]?.*' $REPOS_DIRECTORY/*)

I tried both methods of assigning the array; the first suggestion introduced an error with Shellcheck related to SC2207 and the second suggestion did not trigger any error.

However, if I remove the comment to disable the SC2048 check on line 16-17, the error returns regardless of how the array is originally assigned.

[alcir]

What about

8     mapfile -t UPDATE_PLATFORM_URLS < <(grep -P -ho 'http[s]?.*' "${REPOS_DIRECTORY}"/*)
9     if [[ ${#UPDATE_PLATFORM_URLS[@]} -eq 0 ]]; then
...
16     for UPDATE_PLATFORM_URL in "${UPDATE_PLATFORM_URLS[@]}"; do

Running shellcheck from command line doesn't return any error and the script works as intended.

[miabbott]

This looks promising...I was heading in this direction but lack of time has kept me from pursuing this fully.

[miabbott]

⬆️ Pushed an update yesterday with the suggestions from @alcir; I did some light testing on a Fedora IoT system and verified it worked with the happy path and unhappy path.

[nullr0ute]

@miabbott so the bats_test is failing, is that a problem or does the test need to be adjusted or is it unrelated to this? Other than that is this ready to review/merge?

[miabbott]

@nullr0ute BATS is failing like this:

not ok 1 Ensure watchdog check is working
# (from function `source' in file /usr/lib/greenboot/check/required.d/02_watchdog.sh, line 47,
#  from function `setup' in test file check_watchdog_support.bats, line 4)
#   `source $GREENBOOT_DEFAULT_CHECK_PATH/required.d/02_watchdog.sh --source-only' failed
# No watchdog on the system, skipping check

Looking at the history of that test on other PRs, it is failing similarly, so I believe it is unrelated to this change.

I believe this is ready for review + merge