pub type MutationRowGate<'a> = &'a (dyn Fn(&[HashMap<String, Value>]) -> Result<()> + Send + Sync);Expand description
Adjudicates the rows a mutation function returned, from inside the transaction that produced them and before it commits.
Ok(()) commits the transaction; Err(e) rolls it back and e reaches the
caller. See Writer::execute_write for why a write needs a decision seam this late
(#1353).
Synchronous by construction: the only decision taken here today is the field
authorizer’s, whose authorize_field is itself synchronous, and holding an open
transaction across an arbitrary await would pin a pooled connection for as long
as app-supplied policy code chose to take.