Crate postage

The feature-rich, portable async channel library.

Why use Postage?

• Includes a rich set of channels.
  • barrier, a oneshot channel that transmits when the sender half is dropped.
  • broadcast, a lossless multi-producer, multi-consumer broadcast channel with backpressure (no lagging!).
  • dispatch, a multi-producer, multi-consumer queue.
  • mpsc, a multi-producer, single-consumer channel.
  • oneshot, a oneshot transfer channel.
  • watch, a state distribution channel with a value that can be borrowed.
• Works with any executor.
  • Currently regressions are written for tokio and async-std.
  • With the futures-traits feature, channels implement the futures Sink/Stream traits.
• Throughly tested.
  • Channels have full unit test coverage, and integration test coverage with multiple async executors.
• Comes with built-in Sink and Stream combinators.
  • Sinks can be chained, and filtered.
  • Streams can be chained, filtered, mapped, and merged.
  • With the logging feature, Sinks and streams can log their values. This is really helpful when debugging applications.

See the readme for benchmarks.

Cargo features:

• blocking (default) - enables Sink::blocking_send and Stream::blocking_recv
• debug - enables extremely verbose internal log statements.
• futures-traits - enables futures::Sink and futures::Stream implementations for the postage channels. Compatible with v0.3.
• logging (default) - enables the enables Sink::log(Level) and Stream::log(Level) combinators.

Modules

barrier

Barriers transmit when the sender half is dropped, and can synchronize events in async tasks.

broadcast

Provides a lossless, MPMC channel. All receivers are guaranteed to recieve each message.

dispatch

A fixed-capacity multi-producer, multi-consumer queue. At most one receiver will observe each value.

mpsc

A fixed-capacity multi-producer, single-consumer channel.

oneshot

Oneshot channels transmit a single value between a sender and a reciever.

prelude

Imports the Sink and Stream traits.

sink

A sink for values which are asynchronously accepted, until the target is closed.

stream

A stream of values which are asynchronously produced, until the source is closed.

watch

A state distribution channel. The internal state can be borrowed or cloned, but receivers do not observe every value.

Structs

Context

The Context of an asynchronous task.