フリー問題

問題文

A mutate rule must add a label only when the resource does not already carry it, leaving an existing value untouched. Which anchor does this?

選択肢

1. The equality anchor, written as an equals sign before the parentheses, because it makes the mutation conditional on the tag being absent and therefore only writes when there is nothing to overwrite.
2. The conditional anchor, written as parentheses around the tag of the container image field.
3. The add-if-not-present anchor, written as a plus sign before the parentheses.
4. No anchor is needed, because a strategic merge patch never overwrites a field whose value is already set and only fills in the fields that are missing from the submitted object.