// convertToDiscoveryAPIGroup takes apiservices in a single group and returns a discovery compatible object.
// if none of the services are available, it will return nil.
func convertToDiscoveryAPIGroup(apiServices []*apiregistrationapi.APIService, serviceLister v1listers.ServiceLister, endpointsLister v1listers.EndpointsLister) *metav1.APIGroup {
apiServicesByGroup := apiregistrationapi.SortedByGroup(apiServices)[0]
var discoveryGroup *metav1.APIGroup
for _, apiService := range apiServicesByGroup {
// skip any API services without actual services
if _, err := serviceLister.Services(apiService.Spec.Service.Namespace).Get(apiService.Spec.Service.Name); err != nil {
continue
}
hasActiveEndpoints := false
endpoints, err := endpointsLister.Endpoints(apiService.Spec.Service.Namespace).Get(apiService.Spec.Service.Name)
// skip any API services without endpoints
if err != nil {
continue
}
for _, subset := range endpoints.Subsets {
if len(subset.Addresses) > 0 {
hasActiveEndpoints = true
break
}
}
if !hasActiveEndpoints {
continue
}
// the first APIService which is valid becomes the default
if discoveryGroup == nil {
discoveryGroup = &metav1.APIGroup{
Name: apiService.Spec.Group,
PreferredVersion: metav1.GroupVersionForDiscovery{
GroupVersion: apiService.Spec.Group + "/" + apiService.Spec.Version,
Version: apiService.Spec.Version,
},
}
}
discoveryGroup.Versions = append(discoveryGroup.Versions,
metav1.GroupVersionForDiscovery{
GroupVersion: apiService.Spec.Group + "/" + apiService.Spec.Version,
Version: apiService.Spec.Version,
},
)
}
return discoveryGroup
}
func (r *apisHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
// if the URL is for OUR api group, serve it normally
if strings.HasPrefix(req.URL.Path+"/", "/apis/"+apiregistrationapi.GroupName+"/") {
r.delegate.ServeHTTP(w, req)
return
}
// don't handle URLs that aren't /apis
if req.URL.Path != "/apis" && req.URL.Path != "/apis/" {
r.delegate.ServeHTTP(w, req)
return
}
discoveryGroupList := &metav1.APIGroupList{
// always add OUR api group to the list first. Since we'll never have a registered APIService for it
// and since this is the crux of the API, having this first will give our names priority. It's good to be king.
Groups: []metav1.APIGroup{discoveryGroup},
}
apiServices, err := r.lister.List(labels.Everything())
if err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
apiServicesByGroup := apiregistrationapi.SortedByGroup(apiServices)
for _, apiGroupServers := range apiServicesByGroup {
// skip the legacy group
if len(apiGroupServers[0].Spec.Group) == 0 {
continue
}
discoveryGroup := convertToDiscoveryAPIGroup(apiGroupServers, r.serviceLister, r.endpointsLister)
if discoveryGroup != nil {
discoveryGroupList.Groups = append(discoveryGroupList.Groups, *discoveryGroup)
}
}
json, err := runtime.Encode(api.Codecs.LegacyCodec(), discoveryGroupList)
if err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
if _, err := w.Write(json); err != nil {
panic(err)
}
}