Struct Tx 

pub struct Tx<DB>(/* private fields */);

The delivery’s transaction: the handler’s first Ctx, on a registration mounted with .transactional().

It reads TxContext and yields Tx, which goes back to the delivery when the handler ends. A handler reads it once: a second read for one delivery panics, the transaction lent already.

Examples

use ruststream_sqlx::prelude::*;
use sqlx::{PgPool, Postgres};

#[subscriber(InboxQueue::<Job>::new("shipments"))]
async fn ship(shipment: &Shipment, Ctx(mut tx): Ctx<keys::Tx<Postgres>>) -> HandlerOutcome {
    let shipped = sqlx::query("UPDATE orders SET shipped = true WHERE id = $1")
        .bind(shipment.order)
        .execute(&mut *tx)
        .await;
    if shipped.is_ok() { HandlerOutcome::ack() } else { HandlerOutcome::retry() }
}

pub fn app(pool: PgPool) -> RustStream {
    RustStream::new(AppInfo::new("shipping", "0.1.0")).with_broker(SqlxBroker::new(pool), |b| {
        b.include(ship.transactional());
    })
}

Trait Implementations

impl<DB> Clone for Tx<DB>

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<DB: QueueDatabase> ContextField for Tx<DB>

fn read(self, src: &TxContext<DB>) -> Tx<DB>

Lends the delivery’s transaction: one lock, no allocation.

Panics

When the transaction is lent already: a handler reads it once per delivery.

type Context = TxContext<DB>

The per-delivery context type this key reads from.

type Value = Tx<DB>

The owned value the key yields.

impl<DB> Copy for Tx<DB>

impl<DB> Debug for Tx<DB>

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

Formats the value using the given formatter.

impl<DB> Default for Tx<DB>

fn default() -> Self

Returns the “default value” for a type.