Struct Position 

pub struct Position;

Reads this delivery’s own log coordinates, in the form Seeker::seek takes: seeking to them redelivers exactly this record.

Examples

use ruststream_rdkafka::prelude::*;

/// Rewinds to the record it is holding when a downstream dependency is unavailable, so
/// the partition resumes here rather than from the group's committed position.
#[subscriber("orders")]
async fn place(
    order: &Order,
    Ctx(here): Ctx<Position>,
    Ctx(seeker): Ctx<SeekHandle>,
) -> HandlerOutcome {
    if order.id == 0 && seeker.seek(here).await.is_err() {
        return HandlerOutcome::retry();
    }
    HandlerOutcome::ack()
}

Trait Implementations

impl Clone for Position

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl ContextField for Position

type Context = KafkaContext

The per-delivery context type this key reads from.

type Value = KafkaPosition

The owned value the key yields.

fn read(self, src: &KafkaContext) -> KafkaPosition

Reads this key’s field out of src. Named apart from Field::get so a key implementing both traits stays unambiguous to call.

impl Copy for Position

impl Debug for Position

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

Formats the value using the given formatter.

impl Default for Position

fn default() -> Self

Returns the “default value” for a type.

impl Eq for Position

impl Field<KafkaContext> for Position

type Value<'a> = KafkaPosition

The value read through this key, borrowed from the source for 'a.

fn get(self, src: &KafkaContext) -> KafkaPosition

Reads this key’s field out of src.

impl PartialEq for Position

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for Position