prahaladhchandrahasan/hawtio-kubernetes-api

hawtio plugin that maintains an in-memory model of kubernetes objects

hawtio-kubernetes-api

Hawtio plugin that provides an easy API for working with a Kubernetes or OpenShift API server.

Usage

To use the API, inject it into a service or controller:

  angular.module('my-awesome-stuff', ['KubernetesAPI']).controller('MyController', function($scope, K8SClientFactory) {

  });

The K8SClientFactory service implements this interface for managing client instances:

  export interface K8SClientFactory {
    create(kind:string, namespace?: string):Collection;
    destroy(client:Collection, ...handles:Array<(data:any[]) => void>):void;
  }

create will give you an object that implements this interface:

  export interface Collection {
    wsURL:string;
    restURL:string;
    namespace: string;
    kind: string;
    connected: boolean;
    connect();
    get(cb:(data:any[]) => void):void;
    watch(cb:(data:any[]) => void):void;
    unwatch(cb:(data:any[]) => void):void;
    put(item:any, cb:(data:any) => void, error?:(err:any) => void):void;
    delete(item:any, cb:(data:any) => void, error?:(err:any) => void):void;
    getKey():string;
  }

Supported watch types along with the above interfaces are exported from kubernetesApiInterfaces.ts.

Typical usage would be to create a client, and watch that client for changes. Here's an example:

  angular.module('my-awesome-stuff', ['KubernetesAPI']).controller('MyController', function($scope, $element, K8SClientFactory) {

      $scope.kind = 'pods';
      $scope.namespace = 'default';

      // create our client instance...
      var client = $scope.client = K8SClientFactory.create(kind, namespace);

      // set up a watch here, important to save the returned 'handle' object
      // for cleaning up later...
      var handle = client.watch(function(objects) {
        console.log("Callback fired for kind: ", kind);
        $scope.objects = objects;
        // have to kick off a $digest here
        $scope.$apply();
      });

      // You can use watchCollection to do stuff in angular's event loop if you
      // like
      $scope.$watchCollection('objects', function(newValue) {
        console.log($scope.objectKind + " collection changed");
      });

      $scope.delete = function(obj) {

        // Deleting an object, you just pass the whole object in.
        client.delete(obj, function(obj) {
          console.log("Deleted: ", obj);
        });
      };

      $scope.create = function() {
        var item = _.cloneDeep(_.sample($scope.objects));
        delete item.metadata.resourceVersion;
        delete item.metadata.uid;
        item.metadata.name = "new-" + item.metadata.name;

        // Here we're creating an object...  Since we're watching we'll just let 'watch' update our collection
        client.put(item, function(obj) {
          console.log("Created: ", obj);
        });
      };

      // client instances to an object collection are shared, important to use
      // the factory to destroy instances and avoid leaking memory
      $element.on('$destroy', function {
        $scope.$destroy();
      });
      $scope.$on('$destroy', function {
        K8SClientFactory.destroy(client, handle);
      });

      // This actually connects the client.
      client.connect();
  });

Developing

Output build to a different directory

When developing this plugin in a dependent console you can change the output directory where the compiled .js and .css go. Just use the 'out' flag to set a different output directory, for example:

gulp watch --out=../fabric8-console/libs/hawtio-kubernetes-api/dist/

Whenever the build completes the compiled .js file will be put into the target directory. Don't forget to first do a gulp build without this flag before committing changes!

Turn on source maps generation for debugging TypeScript

If you want to debug .ts using a browser developer tool such as Chrome DevTools, pass the --sourcemap flag:

yarn start --sourcemap

Do not use this flag when you are committing the compiled .js file, as it embeds source maps to the output file. Use this flag only during development.

Minikube

To make the example work, you would need to configure CORS Allowed Origins for the API server so that the Kubernetes endpoints can be invoked from JavaScript.

minikube start --extra-config apiserver.cors-allowed-origins=["http://*"]