Struct Builder 

pub struct Builder { /* private fields */ }

Builder for a weighted channel. Use channel for the common case.

Implementations

impl Builder

pub fn new(buffer: usize, max_weight: usize) -> Self

Create a builder with the two required bounds:

• buffer: the message-count buffer of the underlying tokio channel. It is the backstop for zero- or near-zero-weight messages, which the weight budget alone would not bound. Must be > 0.
• max_weight: the total weight allowed in the channel at once. Must be in 1..=u32::MAX (about 4 GiB).

Defaults: Oversized::Allow, min_weight of 1, and no observer.

pub fn min_weight(self, min_weight: usize) -> Self

Minimum weight counted for any message. A message lighter than this still takes this much budget, so a flood of tiny messages cannot fill the channel without the budget noticing. Defaults to 1; set it to 0 to let zero-weight messages through without taking any budget (then only buffer bounds them).

pub fn oversized(self, policy: Oversized) -> Self

How to handle a message that weighs more than the whole budget. See Oversized.

pub fn on_oversized<F>(self, hook: F) -> Self

where F: Fn(usize, usize) + Send + Sync + 'static,

Register an observer called as (message_weight, max_weight) whenever a message weighs more than the budget, whatever the Oversized choice.

pub fn build<T>(self) -> (WeightedSender<T>, WeightedReceiver<T>)

Build the sender/receiver pair.

Panics

Panics if buffer is 0, or if max_weight is 0 or greater than u32::MAX.

Trait Implementations

impl Clone for Builder

fn clone(&self) -> Builder

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Builder

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

Formats the value using the given formatter.