Struct Channel 

pub struct Channel<T> { /* private fields */ }

Defines one durable FIFO queue of typed messages.

Add the Channel to crate::PersistenceSchema. Clients and handlers may publish messages; Steps create Condition values that wait for queue-size bounds and read the messages consumed by the satisfied condition.

Examples

use dex_sdk::{Channel, Wait};

let approvals = Channel::<String>::new("approvals");
let wait = Wait::until(approvals.for_one());

Implementations

impl<T> Channel<T>

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

Defines a Channel with stable name.

pub fn publish(&self, context: &mut Context, value: T) -> HandlerResult<()>

where T: Value,

Stages one message from the current Step or RPC invocation.

Errors

Returns a crate::HandlerError when value cannot be encoded.

pub fn size(&self, context: &Context) -> HandlerResult<usize>

Returns the invocation snapshot’s queued-message count.

pub fn condition_results(&self, context: &Context) -> HandlerResult<Vec<T>>

where T: Value,

Decodes messages consumed by this Channel’s satisfied condition.

Errors

Returns a crate::HandlerError when a message cannot be decoded.

pub fn for_one(&self) -> Condition

Creates a condition that consumes exactly one queued message.

pub fn for_n(&self, count: usize) -> Condition

Creates a condition that consumes exactly count queued messages.

pub fn at_least(&self, count: usize) -> Condition

Creates a condition satisfied when at least count messages are queued.

pub fn at_most(&self, count: usize) -> Condition

Creates a condition satisfied when no more than count messages are queued.

pub fn range( &self, at_least: Option<usize>, at_most: Option<usize>, ) -> Condition

Creates a condition with optional inclusive lower and upper queue-size bounds.

pub fn when_empty(&self) -> ChannelGuard

Creates a guard used by conditional Flow completion to require an empty queue.

Trait Implementations

impl<T> Clone for Channel<T>

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.