submoduleVersionCheck.sh

#!/bin/bash
set -e

# Script checks if commit id of the git submodule in a PR branch is older than the one in a main branch or remote.
# If commit id is older then error is thrown.
# pseudocode:
#   if local_commit_id == main_branch_commit_id
#   then OK
#   else check remote submodule id
#       if local_commit_id == remote_commit_id
#       then OK
#       else throw Error


function create_temp_submodule_folder() {
    temp_dir=$(mktemp -d)
    cp .gitmodules "${temp_dir}"
    cp -R .github "${temp_dir}"
    cp -R .git "${temp_dir}"
    echo "${temp_dir}"
}

function get_submodule_version() {
    git_submodule_name=$1
    IFS=$'\n'
    git_submodules=$(git submodule status)
    for item in $git_submodules
    do
       if [[ $item == *"${git_submodule_name}"* ]]; then
            submodule="${item:1}"
            submodule_id="${submodule%%common-dev-assets*}"
            break
        fi
    done
    echo "${submodule_id}"
}

function submodule_exists(){
    git_submodule_name=$1
    git_submodules=$(git submodule status)
    exists=false
    if [ -e ".gitmodules" ]
    then
        while IFS= read -r line ; do
            if [[ $line == *"${git_submodule_name}"* ]]; then
                exists=true
                break
            fi
        done <<< "${git_submodules}"
    fi
    echo "${exists}"
}

function main() {
    # execute only if repo has common-dev-assets submodule
    git_submodule_name="common-dev-assets"
    git_submodule_exists=$(submodule_exists ${git_submodule_name})

    if [ "${git_submodule_exists}" = true  ]
    then
        temp_dir=$(create_temp_submodule_folder)
        cd "${temp_dir}"

        # current submodule version
        submodule_version_current=$(get_submodule_version ${git_submodule_name})

        # rebase submodule version with main branch
        git submodule update --rebase
        submodule_version_main_branch=$(get_submodule_version ${git_submodule_name})

        if [ "${submodule_version_current}" != "${submodule_version_main_branch}" ]; then
            # update submodule version with remote
            git submodule update --remote --merge
            submodule_version_remote=$(get_submodule_version ${git_submodule_name})

            if [ "${submodule_version_current}" != "${submodule_version_remote}" ]; then
                printf "\nDetected common-dev-assets git submodule commit ID is older than the one in primary branch. Run the following command to sync with primary branch: git submodule update --rebase"
                rm -fr "${temp_dir}"
                exit 1
            fi
        fi
        rm -fr "${temp_dir}"
    fi
}

main