kube-discovery

Use case:

"I've got a test setup on my Kubernetes cluster, but I don't want to keep updating my environment variables with locations and authentication info. Can't I just access the cluster and load relevant data from there?"

Limitations

This crate is written for my specific use case, so some of the assumptions it makes might not make sense for other setups.
Note: This crate imports k8s_openapi with a fixed Kubernetes version. Make sure to enable the corresponding v1-feature for that respective version. Also, make sure use kube_discovery::kube as kube crate, and kube_discovery::k8s_openapi as k8s_openapi crate. That way you'll avoid versioning conflicts.

Example (Location Discovery)

use kube_discovery::k8s_openapi::api::core::v1::Service;
use kube_discovery::kube::{
    api::{DeleteParams, PostParams},
    Api, Client, Config,
};
use kube_discovery::*;

#[tokio::main]
async fn main() {
    // doctest setup
    let kube_config = Config::infer().await.unwrap();
    let kube_client = Client::try_from(kube_config.clone()).unwrap();
    let svc_api: Api<Service> = Api::namespaced(kube_client.clone(), "scratch");

    // Say you've got a service like this
    let service_with_nodeport: Service = serde_yaml::from_str(
        "
    apiVersion: v1
    kind: Service
    metadata:
      name: doctest-example
      labels:
        app: doctest-example
    spec:
      type: NodePort
      selector:
        app: example-app
      ports:
      - protocol: TCP
        port: 80
        targetPort: 8080
        nodePort: 31234
    ",
    )
    .unwrap();
    svc_api
        .create(&PostParams::default(), &service_with_nodeport)
        .await
        .unwrap();

    // Instead of storing the service's public url in some environment variable
    // (or, heavens forbid, even hardcoding it), just load the location based
    // on the service's labels.
    let service_uri = LabelSelector("app=doctest-example")
        .load_service_host(&kube_config, &kube_client)
        .await
        .unwrap();

    assert_eq!(service_uri, "162.55.38.94:31234");

    // doctest cleanup
    svc_api
        .delete("doctest-example", &DeleteParams::default())
        .await
        .unwrap();
}

License

MIT OR Apache-2.0