fix(md5): check avaiable and platform fix

BSD uses 'md5', not 'md5sum'

CHANGELOG.md

@@ -24,6 +24,10 @@
 
 ## Unreleased...
 
+* Fix: check for `md5` availability in platform indepedent way.
+  Removes need to install coreutils on Mac.
+  [#642](https://github.com/Kong/kong-pongo/pull/642).
+
 ---
 
 ## 2.15.0 released 17-Dec-2024

pongo.sh

@@ -64,7 +64,7 @@ function globals {
   fi
 
   # create unique projectID based on file-path (on the host machine)
-  PROJECT_ID=$(echo -n "$PONGO_WD" | md5sum)
+  PROJECT_ID=$(echo -n "$PONGO_WD" | $MD5_COMMAND )
   PROJECT_ID="${PROJECT_ID:0:8}"
 
   PROJECT_NAME_PREFIX="pongo-"
@@ -232,6 +232,21 @@ function check_tools {
     missing=true
   fi
 
+  # Detect the MD5 command
+  if command -v md5sum &> /dev/null; then
+    # Unix
+    MD5_COMMAND="md5sum"
+  elif command -v gmd5sum &> /dev/null; then
+    # GNU
+    MD5_COMMAND="gmd5sum"
+  elif command -v md5 &> /dev/null; then
+    # BSD/Mac
+    MD5_COMMAND="md5"
+  else
+    >&2 echo "'md5sum', 'gmd5sum', and 'md5' commands not found, please install anyone of them, and make it available in the path."
+    missing=true
+  fi
+
   if [[ "$missing" == "true" ]]; then
     >&2 echo -e "\033[0;31m[pongo-ERROR] the above dependencies are missing, install and retry.\033[0m"
     exit 1