Implementation:Fede1024 Rust rdkafka AsyncStdRuntime Adapter

Knowledge Sources	Fede1024_Rust_rdkafka async-std
Domains	Async_Runtime, Runtime_Abstraction, Integration
Last Updated	2026-02-07 19:00 GMT

Overview

Example implementation of the AsyncRuntime trait that integrates rust-rdkafka with the async-std runtime, demonstrating pluggable async runtime support.

Description

The runtime_async_std example defines a custom AsyncStdRuntime struct that implements rdkafka::util::AsyncRuntime. It maps spawn to async_std::task::spawn and delay_for to async_std::task::sleep, using Pin<Box<dyn Future<Output = ()> + Send>> as the Delay associated type. The main function, annotated with #[async_std::main], sends a single message through a FutureProducer<_, AsyncStdRuntime> and receives it with a StreamConsumer<_, AsyncStdRuntime>, verifying the roundtrip works under async-std.

Usage

Use this as a reference when integrating rust-rdkafka with the async-std runtime instead of the default Tokio. Copy the AsyncStdRuntime struct and trait implementation into your project, then parameterize producers and consumers with it.

Code Reference

Source Location

• Repository: Fede1024_Rust_rdkafka
• File: examples/runtime_async_std.rs
• Lines: 1-108

Signature

pub struct AsyncStdRuntime;

impl AsyncRuntime for AsyncStdRuntime {
    type Delay = Pin<Box<dyn Future<Output = ()> + Send>>;

    fn spawn<T>(task: T)
    where
        T: Future<Output = ()> + Send + 'static,
    {
        async_std::task::spawn(task);
    }

    fn delay_for(duration: Duration) -> Self::Delay {
        Box::pin(async_std::task::sleep(duration))
    }
}

Import

use rdkafka::util::AsyncRuntime;
use std::future::Future;
use std::pin::Pin;
use std::time::Duration;

I/O Contract

Inputs

Name	Type	Required	Description
task	impl Future<Output = ()> + Send + 'static	Yes	Async task to spawn on async-std
duration	Duration	Yes	Sleep duration for delay_for

Outputs

Name	Type	Description
Delay	Pin<Box<dyn Future<Output = ()> + Send>>	Boxed sleep future from async-std

Usage Examples

Using AsyncStdRuntime with Producer and Consumer

use rdkafka::config::ClientConfig;
use rdkafka::consumer::StreamConsumer;
use rdkafka::producer::FutureProducer;

// Define the runtime adapter
pub struct AsyncStdRuntime;
impl rdkafka::util::AsyncRuntime for AsyncStdRuntime {
    type Delay = Pin<Box<dyn Future<Output = ()> + Send>>;
    fn spawn<T: Future<Output = ()> + Send + 'static>(task: T) {
        async_std::task::spawn(task);
    }
    fn delay_for(duration: Duration) -> Self::Delay {
        Box::pin(async_std::task::sleep(duration))
    }
}

// Create producer with async-std runtime
let producer: FutureProducer<_, AsyncStdRuntime> = ClientConfig::new()
    .set("bootstrap.servers", "localhost:9092")
    .create()
    .expect("Producer creation failed");

// Create consumer with async-std runtime
let consumer: StreamConsumer<_, AsyncStdRuntime> = ClientConfig::new()
    .set("bootstrap.servers", "localhost:9092")
    .set("group.id", "my-group")
    .create()
    .expect("Consumer creation failed");

Related Pages

• Environment:Fede1024_Rust_rdkafka_Rust_Librdkafka_Build_Environment