dr_check_component()

Extension packages implement this S3 generic alongside their read, transform, quality, target or catalog method. Validate configuration and dependencies; do not fetch data, execute user callbacks or write anything. Return x invisibly or raise an actionable error. Passing preflight does not prove that remote resources are available or that the data meet their contract.

dr_check_component(x, ...)

dr_check_component(dr_quality_rule("nonnegative", ~ amount >= 0))