Crate instance_chart

Provides data about other instances on the same machine/network

This crate provides a lightweight alternative to mDNS. It discovers other instances on the same network or (optionally) machine. You provide an Id and some data you want to share. Usually this is a port your service uses. This gives you a live updating chart of all the discovered Ids-data pairs and the corrosponding ip adresses.

The chart can contain instances that are now down. It can not be used to check if a service is up.

Usage

Add a dependency on instance-chart in Cargo.toml:

instance_chart = "0.1"

Now add the following snippet somewhere in your codebase. Discovery will stop when you drop the maintain future.

use std::error::Error;
use instance_chart::{discovery, ChartBuilder};

#[tokio::main]
async fn main() -> Result<(), Box<dyn Error>> {
   let chart = ChartBuilder::new()
       .with_id(1)
       .with_service_port(8042)
       .finish()?;
   let maintain = discovery::maintain(chart.clone());
   let _ = tokio::spawn(maintain); // maintain task will run forever
   Ok(())
}

Modules

discovery

Structs

Chart

The chart keeping track of the discoverd nodes. That a node appears in the chart is no guarentee that it is reachable at this moment.

ChartBuilder

Construct a Chart using a builder-like pattern. You must always set an id. You also need to set service port or service ports and build with finish() or set a custom msg and build using custom_msg(). See the examples of ChartBuilder::custom_msg() or ChartBuilder::finish().

Notify

Wait for notifications of new discoveries, buffering up to 16 discoveries, created using Chart::notify().

Enums

Error