ReadonlyIF_Overwrite only if source object is newer than destination. Comparison based on Last-Modified timestamp. Recommended for incremental sync scenarios. If touch_unmanaged flag isn't set, we do not overwrite objects that haven't been created by Data Transfer service.
ReadonlyNEVERNever overwrite objects that exist in the destination. If object exists in destination bucket, skip it. Safest option to prevent any data loss.
ReadonlyOVERWRITE_Represents the OVERWRITE_STRATEGY_UNSPECIFIED protobuf enum value.
Defines the static values of TransferSpec_OverwriteStrategy.