Wrap a daf with a contract for a computation

When contract enforcement is enabled (env DAF_ENFORCE_CONTRACTS=1 or options(dafr.enforce_contracts = TRUE)), returns a ContractDaf that tracks access and rejects operations outside contract. Otherwise returns daf unchanged.

Usage

contractor(computation, contract, daf, name = NULL, overwrite = FALSE)

Arguments

computation: Name of the computation (character scalar).
contract: A Contract() describing expected inputs and outputs.
daf: The underlying DafReader / DafWriter.
name: Optional name for the wrapper; defaults to <daf-name>.<computation>.
overwrite: If TRUE, pre-existing CreatedOutput properties are allowed.

Value

daf itself, or a ContractDaf wrapping it.

Examples

withr::with_options(list(dafr.enforce_contracts = TRUE), {
    c <- Contract(
        axes = list(cell = list(RequiredInput, "per-cell axis")),
        data = list(contract_vector("cell", "donor",
            RequiredInput, "character", "donor id"))
    )
    d <- memory_daf()
    add_axis(d, "cell", c("c1", "c2"))
    set_vector(d, "cell", "donor", c("d1", "d2"))
    cd <- contractor("demo", c, d)
    class(cd)[[1]]
})
#> [1] "dafr::ContractDaf"