Use shellcheck for better compatibility in mde_installer.sh

[SvenMarquardt5772]

I would suggest to use https://www.shellcheck.net/, to verify that the script works in more environments and also to have some sort of static code analysis.

Here is the current output of shellcheck.

In mde_installer.sh line 64:
    msg="${@:3}"
        ^------^ SC2124: Assigning an array to a string! Assign as array, or use * instead of @ to concatenate.


In mde_installer.sh line 101:
    if [ -n $DEBUG ]; then
            ^----^ SC2070: -n doesn't work with unquoted arguments. Quote or use [[ ]].


In mde_installer.sh line 117:
	    exit $2
                 ^-- SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
	    exit "$2"


In mde_installer.sh line 122:
   if which python3 &> /dev/null; then
      ^---^ SC2230: which is non-standard. Use builtin 'command -v' instead.


In mde_installer.sh line 124:
   elif which python2 &> /dev/null; then
        ^---^ SC2230: which is non-standard. Use builtin 'command -v' instead.


In mde_installer.sh line 133:
   cat <<EOF | /usr/bin/env $(get_python)
                            ^-----------^ SC2046: Quote this to prevent word splitting.


In mde_installer.sh line 172:
    echo $proxy_params
         ^-----------^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
    echo "$proxy_params"


In mde_installer.sh line 177:
    if [ -z $(which mdatp) ]; then
            ^------------^ SC2046: Quote this to prevent word splitting.
              ^---^ SC2230: which is non-standard. Use builtin 'command -v' instead.


In mde_installer.sh line 200:
    local out=$(eval $1 2>&1; echo "$?")
          ^-^ SC2155: Declare and assign separately to avoid masking return values.
                     ^-- SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
    local out=$(eval "$1" 2>&1; echo "$?")


In mde_installer.sh line 201:
    local exit_code=$(echo "$out" | tail -n1)
          ^-------^ SC2155: Declare and assign separately to avoid masking return values.


In mde_installer.sh line 208:
        if [ -n $DEBUG ]; then
                ^----^ SC2070: -n doesn't work with unquoted arguments. Quote or use [[ ]].


In mde_installer.sh line 215:
            log_error $2
                      ^-- SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
            log_error "$2"


In mde_installer.sh line 221:
    return $exit_code
           ^--------^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
    return "$exit_code"


In mde_installer.sh line 237:
    while [ $retries -gt 0 ]
            ^------^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
    while [ "$retries" -gt 0 ]


In mde_installer.sh line 249:
            log_info "[r] $(($1-$retries))/$1"
                                ^------^ SC2004: $/${} is unnecessary on arithmetic variables.


In mde_installer.sh line 266:
        . /etc/os-release
          ^-------------^ SC1091: Not following: /etc/os-release was not specified as input (see shellcheck -x).


In mde_installer.sh line 273:
        elif [[ $(grep -o -i "Red\ Hat" /etc/redhat-release) ]]; then
                ^-- SC2143: Use grep -q instead of comparing output with [ -n .. ].


In mde_installer.sh line 275:
        elif [[ $(grep -o -i "Centos" /etc/redhat-release) ]]; then
                ^-- SC2143: Use grep -q instead of comparing output with [ -n .. ].


In mde_installer.sh line 309:
    if which wget; then
       ^---^ SC2230: which is non-standard. Use builtin 'command -v' instead.


In mde_installer.sh line 311:
    elif which curl; then
         ^---^ SC2230: which is non-standard. Use builtin 'command -v' instead.


In mde_installer.sh line 353:
    if [ $(id -u) -ne 0 ]; then
         ^------^ SC2046: Quote this to prevent word splitting.


In mde_installer.sh line 362:
    local cores=$(nproc --all)
          ^---^ SC2155: Declare and assign separately to avoid masking return values.


In mde_installer.sh line 363:
    if [ $cores -lt $MIN_CORES ]; then
         ^----^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
    if [ "$cores" -lt $MIN_CORES ]; then


In mde_installer.sh line 367:
    local mem_mb=$(free -m | grep Mem | awk '{print $2}')
          ^----^ SC2155: Declare and assign separately to avoid masking return values.


In mde_installer.sh line 368:
    if [ $mem_mb -lt $MIN_MEM_MB ]; then
         ^-----^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
    if [ "$mem_mb" -lt $MIN_MEM_MB ]; then


In mde_installer.sh line 372:
    local disk_space_mb=$(df -m . | tail -1 | awk '{print $4}')
          ^-----------^ SC2155: Declare and assign separately to avoid masking return values.


In mde_installer.sh line 373:
    if [ $disk_space_mb -lt $MIN_DISK_SPACE_MB ]; then
         ^------------^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
    if [ "$disk_space_mb" -lt $MIN_DISK_SPACE_MB ]; then


In mde_installer.sh line 386:
	lines=$(systemctl status $1 2>&1 | grep "Active: active" | wc -l)
                                 ^-- SC2086: Double quote to prevent globbing and word splitting.
                                           ^-------------------^ SC2126: Consider using grep -c instead of grep|wc -l.

Did you mean: 
	lines=$(systemctl status "$1" 2>&1 | grep "Active: active" | wc -l)


In mde_installer.sh line 388:
    if [ $lines -eq 0 ]; then
         ^----^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
    if [ "$lines" -eq 0 ]; then


In mde_installer.sh line 400:
    local conflicting_apps=$(timeout 5m find /proc/*/fdinfo/ -type f -print0 2>/dev/null | xargs -r0 grep -Fl "fanotify mnt_id" 2>/dev/null | xargs -I {} -r sh -c 'cat "$(dirname {})/../cmdline"')
          ^--------------^ SC2155: Declare and assign separately to avoid masking return values.
                                                                                                                                                                   ^-- SC2016: Expressions don't expand in single quotes, use double quotes for that.


In mde_installer.sh line 402:
    if [ ! -z $conflicting_apps ]; then
         ^-- SC2236: Use -n instead of ! -z.
              ^---------------^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
    if [ ! -z "$conflicting_apps" ]; then


In mde_installer.sh line 417:
        set -- $t
               ^-- SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
        set -- "$t"


In mde_installer.sh line 419:
        if find_service $1; then
                        ^-- SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
        if find_service "$1"; then


In mde_installer.sh line 458:
        dpkg -s $1 2> /dev/null | grep Status | grep "install ok installed" 1> /dev/null
                ^-- SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
        dpkg -s "$1" 2> /dev/null | grep Status | grep "install ok installed" 1> /dev/null


In mde_installer.sh line 460:
        rpm --quiet --query $(get_rpm_proxy_params) $1
                            ^---------------------^ SC2046: Quote this to prevent word splitting.
                                                    ^-- SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
        rpm --quiet --query $(get_rpm_proxy_params) "$1"


In mde_installer.sh line 483:
    if [ ! -z "$pkgs_to_be_installed" ]; then
         ^-- SC2236: Use -n instead of ! -z.


In mde_installer.sh line 498:
        lines=$(ps axo pid,comm | grep "$PKG_MGR" | grep -v grep -c)
                ^-- SC2009: Consider using pgrep instead of grepping ps output.


In mde_installer.sh line 512:
    local packages=
          ^------^ SC2178: Variable was used as an array but is now assigned a string.


In mde_installer.sh line 514:
    local success=
          ^-----^ SC2034: success appears unused. Verify use (or export if used externally).


In mde_installer.sh line 524:
    install_required_pkgs ${packages[@]}
                          ^------------^ SC2068: Double quote array expansions to avoid re-splitting elements.


In mde_installer.sh line 553:
    local packages=
          ^------^ SC2178: Variable was used as an array but is now assigned a string.


In mde_installer.sh line 564:
    repo=packages-microsoft-com
         ^--------------------^ SC2100: Use $((..)) for arithmetics, e.g. i=$((i - 2))


In mde_installer.sh line 568:
        packages=($packages deltarpm)
                  ^-------^ SC2128: Expanding an array without an index only gives the first element.
                  ^-------^ SC2206: Quote to prevent word splitting/globbing, or split robustly with mapfile or read -a.


In mde_installer.sh line 571:
    install_required_pkgs ${packages[@]}
                          ^------------^ SC2068: Double quote array expansions to avoid re-splitting elements.


In mde_installer.sh line 575:
        repo=packages-microsoft-com-prod
             ^-------------------------^ SC2100: Use $((..)) for arithmetics, e.g. i=$((i - 2))


In mde_installer.sh line 601:
    local packages=
          ^------^ SC2178: Variable was used as an array but is now assigned a string.


In mde_installer.sh line 611:
    repo=packages-microsoft-com
         ^--------------------^ SC2100: Use $((..)) for arithmetics, e.g. i=$((i - 2))


In mde_installer.sh line 614:
    install_required_pkgs ${packages[@]}
                          ^------------^ SC2068: Double quote array expansions to avoid re-splitting elements.


In mde_installer.sh line 620:
    lines=$($PKG_MGR_INVOKER lr | grep "packages-microsoft-com-$CHANNEL" | wc -l)
                                  ^-- SC2126: Consider using grep -c instead of grep|wc -l.


In mde_installer.sh line 622:
    if [ $lines -eq 0 ]; then
         ^----^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
    if [ "$lines" -eq 0 ]; then


In mde_installer.sh line 648:
    local packages=
          ^------^ SC2178: Variable was used as an array but is now assigned a string.


In mde_installer.sh line 659:
    install_required_pkgs ${packages[@]}
                          ^------------^ SC2068: Double quote array expansions to avoid re-splitting elements.


In mde_installer.sh line 685:
            repo=packages-microsoft-com-prod
                 ^-------------------------^ SC2100: Use $((..)) for arithmetics, e.g. i=$((i - 2))


In mde_installer.sh line 731:
    for version in ${SUPPORTED_RHEL6_VERSIONS[@]}; do
                   ^----------------------------^ SC2068: Double quote array expansions to avoid re-splitting elements.


In mde_installer.sh line 744:
            if rhel6_supported_version $VERSION; then # support versions 6.7+
                                       ^------^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
            if rhel6_supported_version "$VERSION"; then # support versions 6.7+


In mde_installer.sh line 792:
        PYTHON=$(which python || which python3)
                 ^---^ SC2230: which is non-standard. Use builtin 'command -v' instead.
                                 ^---^ SC2230: which is non-standard. Use builtin 'command -v' instead.


In mde_installer.sh line 794:
        if [ -z $PYTHON ]; then
                ^-----^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
        if [ -z "$PYTHON" ]; then


In mde_installer.sh line 824:
    if [ $(mdatp health --field passive_mode_enabled | tail -1) == "false" ]; then
         ^-- SC2046: Quote this to prevent word splitting.


In mde_installer.sh line 838:
        set -- $t
               ^-- SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
        set -- "$t"


In mde_installer.sh line 840:
            local set_tags=$(mdatp health --field edr_device_tags)
                  ^------^ SC2155: Declare and assign separately to avoid masking return values.


In mde_installer.sh line 843:
            local result=$(echo "$set_tags" | grep -q "\"key\":\"$1\""; echo "$?")
                  ^----^ SC2155: Declare and assign separately to avoid masking return values.


In mde_installer.sh line 844:
            if [ $result -eq 0 ]; then
                 ^-----^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
            if [ "$result" -eq 0 ]; then


In mde_installer.sh line 845:
                local value=$(echo "$set_tags" | grep -o "\"key\":\"$1\".*\"" | cut -d '"' -f 8)
                      ^---^ SC2155: Declare and assign separately to avoid masking return values.


In mde_installer.sh line 854:
                local tag_value="\"${@:2}\""
                                ^----------^ SC2124: Assigning an array to a string! Assign as array, or use * instead of @ to concatenate.


In mde_installer.sh line 1076:
if [ ! -z $PASSIVE_MODE ]; then
     ^-- SC2236: Use -n instead of ! -z.


In mde_installer.sh line 1080:
if [ ! -z $ONBOARDING_SCRIPT ]; then
     ^-- SC2236: Use -n instead of ! -z.
          ^----------------^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
if [ ! -z "$ONBOARDING_SCRIPT" ]; then

For more information:
  https://www.shellcheck.net/wiki/SC2068 -- Double quote array expansions to ...
  https://www.shellcheck.net/wiki/SC2070 -- -n doesn't work with unquoted arg...
  https://www.shellcheck.net/wiki/SC2034 -- success appears unused. Verify us...

I would also suggest addressing these warnings and errors.

[agarwalneetu]

@SvenMarquardt5772, is this issue still open? can I start working on this?

[SvenMarquardt5772]

@SvenMarquardt5772, is this issue still open? can I start working on this?

Yes, this is still an issue, This should be part of the pipeline.

[agarwalneetu]

@SvenMarquardt5772, which pipeline you are referring to?

[SvenMarquardt5772]

The one you are using for Continuous Integration. I suppose if you don't have one here on GitHub you have one internally where your tests are running after commits on main. Or whatever QA process you have.