Rust Kuberhealthy Client and Example

This repository provides a minimal library and example check for reporting results back to Kuberhealthy. The reusable client library now lives in the kuberhealthy-client subcrate and can be imported into your own Rust programs. The repository root contains the kuberhealthy-example binary, which demonstrates how to use the client in a check container.

Using the client library

Add the crate to your Cargo.toml:

[dependencies]
kuberhealthy-client = "0.1"

Example usage:

use kuberhealthy_client::KuberhealthyClient;

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let client = KuberhealthyClient::from_env()?;
    // Perform check logic here...
    client.report_success()?;
    Ok(())
}

The client reads the KH_REPORTING_URL and KH_RUN_UUID environment variables provided to every check pod and posts a JSON report with the kh-run-uuid header.

Example check

Run without arguments to report success or with --fail to report a failure.

KH_REPORTING_URL="http://localhost" KH_RUN_UUID="test" cargo run --bin kuberhealthy-example
KH_REPORTING_URL="http://localhost" KH_RUN_UUID="test" cargo run --bin kuberhealthy-example -- --fail

Build and push

Replace the placeholder logic in src/main.rs with your own check logic and then build and publish the container image:

make build          # compile the binary
IMAGE=myrepo/kuberhealthy-rust-example:latest make docker-build
IMAGE=myrepo/kuberhealthy-rust-example:latest make push

Deploy with a KuberhealthyCheck

After the image is pushed, reference it from a KuberhealthyCheck resource:

apiVersion: kuberhealthy.github.io/v2
kind: KuberhealthyCheck
metadata:
  name: rust-example
spec:
  runInterval: 30s
  timeout: 2m
  podSpec:
    containers:
    - name: main
      image: myrepo/kuberhealthy-rust-example:latest
      imagePullPolicy: IfNotPresent

Apply the resource to any cluster where Kuberhealthy is running:

kubectl apply -f khcheck.yaml

Continuous integration and releases

A GitHub Actions workflow builds the example container on every change. When a release is published, another workflow publishes the kuberhealthy-client crate from the subdirectory and pushes the example container image to the GitHub Container Registry.