Expand description
This crate implements a lightweight framework around
kube_runtime::Controller
which provides a simpler interface for common
controller patterns. To use it, you define the data that your controller is
going to operate over, and implement the Context
trait on that struct:
#[derive(Default, Clone)]
struct PodCounter {
pods: Arc<Mutex<BTreeSet<String>>>,
}
impl PodCounter {
fn pod_count(&self) -> usize {
let mut pods = self.pods.lock().unwrap();
pods.len()
}
}
#[async_trait::async_trait]
impl k8s_controller::Context for PodCounter {
type Resource = Pod;
type Error = kube::Error;
const FINALIZER_NAME: &'static str = "example.com/pod-counter";
async fn apply(
&self,
client: Client,
pod: &Self::Resource,
) -> Result<Option<Action>, Self::Error> {
let mut pods = self.pods.lock().unwrap();
pods.insert(pod.meta().uid.as_ref().unwrap().clone());
Ok(None)
}
async fn cleanup(
&self,
client: Client,
pod: &Self::Resource,
) -> Result<Option<Action>, Self::Error> {
let mut pods = self.pods.lock().unwrap();
pods.remove(pod.meta().uid.as_ref().unwrap());
Ok(None)
}
}
Then you can run it against your Kubernetes cluster by creating a
Controller
:
let kube_config = Config::infer().await.unwrap();
let kube_client = Client::try_from(kube_config).unwrap();
let context = PodCounter::default();
let controller = k8s_controller::Controller::namespaced_all(
kube_client,
context.clone(),
watcher::Config::default(),
);
task::spawn(controller.run());
loop {
println!("{} pods running", context.pod_count());
sleep(Duration::from_secs(1));
}
Structs§
- The
Controller
watches a set of resources, calling methods on the providedContext
when events occur.
Traits§
- The
Context
trait should be implemented in order to provide callbacks for events that happen to resources watched by aController
.