Struct AppTransaction 

pub struct AppTransaction { /* private fields */ }

A canonical transaction: operations and preconditions the application contract validates and authorizes, committed atomically.

Implementations

impl AppTransaction

pub fn new(transaction_id: impl Into<String>) -> Self

A transaction with this identity; resubmitting it after an uncertain outcome is safe.

pub fn generated() -> Self

A transaction with a fresh random identity.

pub fn id(&self) -> &str

pub fn insert( self, collection: impl Into<String>, id: impl Into<String>, value: Value, ) -> Self

Create a record that must not exist.

pub fn update( self, collection: impl Into<String>, id: impl Into<String>, value: Value, ) -> Self

Write a record.

pub fn delete( self, collection: impl Into<String>, id: impl Into<String>, ) -> Self

pub fn update_if_version( self, collection: impl Into<String>, id: impl Into<String>, value: Value, version: u64, ) -> Self

Merge value into a record only if its __version is still version. Refused with PRECONDITION_FAILED otherwise; nothing in the transaction is written.

pub fn delete_if_version( self, collection: impl Into<String>, id: impl Into<String>, version: u64, ) -> Self

Delete a record only if its __version is still version. With an AppTransaction::insert of the same id after it, an atomic, fenced replace.

pub fn operation(self, operation: TransactionOperation) -> Self

Any operation of the canonical contract, as the wire document states it.

pub fn precondition(self, precondition: TransactionPrecondition) -> Self

Any precondition of the canonical contract, e.g. a record’s __version:

let tx = AppTransaction::new("tx-1").precondition(TransactionPrecondition::Record {
    collection: "Order".into(),
    id: "o-1".into(),
    require_absent: false,
    expected_version: Some(3),
    expected_epoch: None,
    expected_lease_id: None,
});

pub fn expect_version( self, collection: impl Into<String>, id: impl Into<String>, version: u64, ) -> Self

Commit only if the record’s __version is still version.

pub fn expect_absent( self, collection: impl Into<String>, id: impl Into<String>, ) -> Self

Commit only if the record does not exist.

pub fn fence(self, basis: ReadBasis) -> Self

Commit only if the state basis covers is unchanged since Application::read_basis.

Trait Implementations

impl Clone for AppTransaction

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for AppTransaction

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.