no DeepCopyObject() method for watch.Event type

[fatih]

Hi,

We're using the watch.Event type in our internal code base extensively. Some of the places encode it as well. After upgrading to latest client-go it stopped compiling because of the missing method DeepCopyObject. Seems like the following line is missing (https://github.com/kubernetes/apimachinery/blob/master/pkg/watch/watch.go#L54):

// k8s:deepcopy-gen:interfaces=k8s.io/kubernetes/runtime.Object

Can we generate this method for this type as well? I can open a PR but wasn't sure if that was intentionally like this.

[deads2k]

@sttts

[sttts]

@fatih please take a look at kubernetes/client-go#259. Sounds like the same problem, i.e. vendoring of the wrong apimachinery version.

[fatih]

@sttts Thanks for the info. But we're using now the latest apimachinery and I think this type should have this method anyway as it might be needed (we do now). Is there a way we could add these ?

[sttts]

@fatih got it. I am hestitant to turn watch.Event into an object. It is an internal type not meant to be serialized. It misses the GetObjectKind() schema.ObjectKind implementation as well. Why don't you use metav1.WatchEvent?

[fatih]

@sttts sure, but seems like it's not the same struct. It expects a runtime.RawExtension, not a runtime.Object.

It is an internal type not meant to be serialized

I'm using it for testing a Watch() call from the client. An example from the test I use:

ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
	flusher, ok := w.(http.Flusher)
	if !ok {
		panic("need flusher!")
	}

	w.Header().Set("Transfer-Encoding", "chunked")
	w.WriteHeader(http.StatusOK)
	flusher.Flush()

	scheme := runtime.NewScheme()
	jsonSerializer := kubejson.NewSerializer(
		kubejson.DefaultMetaFactory, scheme, scheme, false)

	encoder := streaming.NewEncoder(w, jsonSerializer)
        // this is the place where it doesn't work anymore as `watch.Event()` doesn't have DeepCopyBoject() anymore
	if err := encoder.Encode(watch.Event{
		Type:   watch.Added,
		Object: obj,
	},
	); err != nil {
		panic(err)
	}

	flusher.Flush()
}))
defer ts.Close()

config := &rest.Config{
	Host: ts.URL,
}

client, err := NewClient(config)
if err != nil {
	t.Fatal(err)
}

// Certificates is a TPR we have implemented internally, but same logic applies to other resources
watcher, err := client.Certificates("default").Watch(metav1.ListOptions{})
if err != nil {
	t.Fatal(err)
}

ch := watcher.ResultChan()
event, ok := <-ch
if !ok {
	t.Errorf("should get a response, didn't have anything")
}

If there is any other solutions I'm happy to test it, but adding the DeepObjectObject() at least is useful for reasons like this (testing).

[sttts]

Compare vendor/k8s.io/apiserver/pkg/endpoints/handlers/watch.go:221. That's the http watch server in kube. It converts the watch.Event to a metav1.Event by essentially writing the embedded runtime.Object into the RawExtension's Object field (in Convert_versioned_InternalEvent_to_versioned_Event). Then the encoder will do the serialization normally.

[fatih]

Thanks @sttts.

[sttts]

@fatih does this work for you? Can we close the issue?

[fatih]

@sttts Sure, thanks for the help again.