optimize terraform plan

tools/terraform.sh

@@ -141,37 +141,43 @@ function tf_plan {
     export CI_PROJECT_DIR=$(git rev-parse --show-toplevel)
   fi
 
+  set +e
   # shellcheck disable=SC2086
   # shellcheck disable=SC2048
-  if ! terraform plan -out "$output.plan" $* | tee "$output"; then
-    echo "error"
-    return
-  fi
-
-
-  echo "... transforming into json ..."
-  terraform show -json "$output.plan" > "$output.json"
-
-
-  jq < "$output.json" '.resource_changes[] | select(.change.actions[] == "create") | .address' -r | sort > "$output.create"
-  # shellcheck disable=SC1083
-  if [[ $(wc -l "$output".create | awk {'print $1'} ) -gt 0 ]]; then
-    printf "\e[92m\e[1mElements to be created .\e[0m\n"
-    sed -e 's#^#+ #' "$output.create"
-  fi
+  terraform plan -detailed-exitcode -out "$output.plan" $* | tee "$output";
+  exitCode=$?
+  set -e
+  #  -detailed-exitcode         Return detailed exit codes when the command exits.
+  #                             This will change the meaning of exit codes to:
+  #                             0 - Succeeded, diff is empty (no changes)
+  #                             1 - Errored
+  #                             2 - Succeeded, there is a diff
+
+  if [[ $exitCode == 2 ]]; then
+    echo "... transforming into json ..."
+    terraform show -json "$output.plan" > "$output.json"
+
+
+    jq < "$output.json" '.resource_changes[] | select(.change.actions[] == "create") | .address' -r | sort > "$output.create"
+    # shellcheck disable=SC1083
+    if [[ $(wc -l "$output".create | awk {'print $1'} ) -gt 0 ]]; then
+      printf "\e[92m\e[1mElements to be created .\e[0m\n"
+      sed -e 's#^#+ #' "$output.create"
+    fi
 
-  jq < "$output.json" '.resource_changes[] | select(.change.actions[] == "delete") | .address' -r | sort > "$output.delete"
-  # shellcheck disable=SC1083
-  if [[ $(wc -l "$output".delete | awk {'print $1'} ) -gt 0 ]]; then
-    printf "\e[91m\e[1mElements to be deleted (or recreated).\e[0m\n"
-    sed -e 's#^#- #'  "$output.delete"
-  fi
+    jq < "$output.json" '.resource_changes[] | select(.change.actions[] == "delete") | .address' -r | sort > "$output.delete"
+    # shellcheck disable=SC1083
+    if [[ $(wc -l "$output".delete | awk {'print $1'} ) -gt 0 ]]; then
+      printf "\e[91m\e[1mElements to be deleted (or recreated).\e[0m\n"
+      sed -e 's#^#- #'  "$output.delete"
+    fi
 
-  jq < "$output.json" '.resource_changes[] | select(.change.actions[] == "update") | .address' -r | sort > "$output.update"
-  # shellcheck disable=SC1083
-  if [[ $(wc -l "$output".update | awk {'print $1'} ) -gt 0 ]]; then
-    printf "\e[93m\e[1mElements to be updated .\e[0m\n"
-    sed -e 's#^# #'  "$output.update"
+    jq < "$output.json" '.resource_changes[] | select(.change.actions[] == "update") | .address' -r | sort > "$output.update"
+    # shellcheck disable=SC1083
+    if [[ $(wc -l "$output".update | awk {'print $1'} ) -gt 0 ]]; then
+      printf "\e[93m\e[1mElements to be updated .\e[0m\n"
+      sed -e 's#^# #'  "$output.update"
+    fi
   fi
 }