remove URI components from metadata host service endpoint when genera…

…ting .mlzconfig (#243)

src/scripts/config/append_prereq_endpoints.sh

@@ -31,8 +31,38 @@ mlz_az_cloud_keys['mlz_keyvaultDns']='suffixes.keyvaultDns'
 mlz_az_cloud_keys['mlz_cloudname']='name'
 mlz_az_cloud_keys['mlz_activeDirectory']='endpoints.activeDirectory'
 
-# since we cannot guarantee the results of `az cloud show` for each value we want,
-# we query for them individually when printing to the file to accommodate for empty results
+# if it's the metadatahost, strip it of URI components
+# in some clouds, Terraform allows only the domain name
+format_if_metadatahost() {
+  local mlz_key_name=$1
+  local cloud_key_value=$2
+
+  if [[ $mlz_key_name != "mlz_metadatahost" ]]; then
+    echo "$cloud_key_value"
+  else
+
+    # 1) awk -F/ '{print $3}'
+    #
+    #   -F/ is "using the character / as a field separator"
+    #
+    #   '{print $3}' is "print me the third field"
+    #
+    # 2) for example on https://management.azure.com/
+    #
+    #   $1      $2 $3                    $4
+    #   https: / / management.azure.com /
+    #
+    #   $1 is https:
+    #   $2 is
+    #   $3 is management.azure.com
+    #   $4 is
+
+    echo "$cloud_key_value" | awk -F/ '{print $3}'
+  fi
+}
+
+# since we cannot guarantee the results of `az cloud show` for each value we require,
+# query for values individually and skip printing any empty results
 append_cloud_value() {
   local mlz_key_name=$1
   local cloud_key_name=$2
@@ -42,7 +72,11 @@ append_cloud_value() {
   cloud_key_value=$(az cloud show --query "${cloud_key_name}" --output tsv)
 
   if [[ $cloud_key_value ]]; then
+    cloud_key_value=$(format_if_metadatahost "$mlz_key_name" "$cloud_key_value")
     printf "%s=%s\n" "${mlz_key_name}" "${cloud_key_value}" >> "${file}"
+  else
+    echo "INFO: Oops! Did not find a value for 'az cloud show --query ${cloud_key_name}'..."
+    echo "INFO: There will not be a value for ${mlz_key_name} on the MLZ config file at ${file}..."
   fi
 }