Crate tokio_prometheus_metered_channel 

Metered channels with Prometheus metrics integration.

This crate provides channel implementations that combine Tokio’s asynchronous channels with Prometheus metrics integration. The channels support proper backpressure through permit-based operations and comprehensive metrics tracking.

Features

• Prometheus metrics integration for monitoring channel behavior
• Cancel-safe permit operations for reliable backpressure handling
• Multiple channel types (mpsc, broadcast, watch) with consistent interfaces
• Comprehensive error handling with detailed error types
• Full test coverage ensuring reliability

Channel Types

• mpsc_channel: Multi-producer, single-consumer channel with metrics
• broadcast_channel: Multi-producer, multi-consumer broadcast channel
• watch_channel: Single-producer, multi-consumer watch channel

Example

use tokio_prometheus_metered_channel::{mpsc_channel, ChannelMetrics};
use prometheus::Registry;

#[tokio::main]
async fn main() {
    // Create a new registry and metrics
    let registry = Registry::new();
    let metrics = ChannelMetrics::new_basic("example", "example channel", &registry).unwrap();
     
    // Create a channel with capacity 10
    let (tx, mut rx) = mpsc_channel(10, metrics);
     
    // Send a value
    tx.send(42).await.unwrap();
     
    // Receive the value
    let value = rx.recv().await.unwrap();
    assert_eq!(value, 42);
}

Credits

This implementation is inspired by and builds upon work from:

• Mysten Labs’ Narwhal project
• Diem’s channel implementations

Re-exports

pub use broadcast::channel as broadcast_channel;

pub use watch::channel as watch_channel;

Modules

broadcast

Broadcast channel implementation with prometheus metrics integration.

prelude

Re-exports of commonly used types

watch

Watch channel implementation with prometheus metrics integration.

Structs

ChannelMetrics

Metrics for channel monitoring

MpscReceiver

A receiver handle to a channel

MpscSender

A sender handle to a channel

Enums

SendError

Error type for channel operations.

Traits

WithPermit

Trait for types that support permit-based sending

Functions

mpsc_channel

Creates a new channel with the given buffer size and metrics

mpsc_channel_with_total

Creates a new channel with total message counting