| /* |
| Copyright 2017 The Kubernetes Authors. |
| |
| Licensed under the Apache License, Version 2.0 (the "License"); |
| you may not use this file except in compliance with the License. |
| You may obtain a copy of the License at |
| |
| http://www.apache.org/licenses/LICENSE-2.0 |
| |
| Unless required by applicable law or agreed to in writing, software |
| distributed under the License is distributed on an "AS IS" BASIS, |
| WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| See the License for the specific language governing permissions and |
| limitations under the License. |
| */ |
| |
| package discovery |
| |
| import ( |
| "net/http" |
| "sync" |
| |
| restful "github.com/emicklei/go-restful" |
| |
| metav1 "k8s.io/apimachinery/pkg/apis/meta/v1" |
| "k8s.io/apimachinery/pkg/runtime" |
| "k8s.io/apimachinery/pkg/runtime/schema" |
| utilnet "k8s.io/apimachinery/pkg/util/net" |
| "k8s.io/apiserver/pkg/endpoints/handlers/negotiation" |
| "k8s.io/apiserver/pkg/endpoints/handlers/responsewriters" |
| ) |
| |
| // GroupManager is an interface that allows dynamic mutation of the existing webservice to handle |
| // API groups being added or removed. |
| type GroupManager interface { |
| AddGroup(apiGroup metav1.APIGroup) |
| RemoveGroup(groupName string) |
| |
| WebService() *restful.WebService |
| } |
| |
| // rootAPIsHandler creates a webservice serving api group discovery. |
| // The list of APIGroups may change while the server is running because additional resources |
| // are registered or removed. It is not safe to cache the values. |
| type rootAPIsHandler struct { |
| // addresses is used to build cluster IPs for discovery. |
| addresses Addresses |
| |
| serializer runtime.NegotiatedSerializer |
| |
| // Map storing information about all groups to be exposed in discovery response. |
| // The map is from name to the group. |
| lock sync.RWMutex |
| apiGroups map[string]metav1.APIGroup |
| // apiGroupNames preserves insertion order |
| apiGroupNames []string |
| } |
| |
| func NewRootAPIsHandler(addresses Addresses, serializer runtime.NegotiatedSerializer) *rootAPIsHandler { |
| // Because in release 1.1, /apis returns response with empty APIVersion, we |
| // use stripVersionNegotiatedSerializer to keep the response backwards |
| // compatible. |
| serializer = stripVersionNegotiatedSerializer{serializer} |
| |
| return &rootAPIsHandler{ |
| addresses: addresses, |
| serializer: serializer, |
| apiGroups: map[string]metav1.APIGroup{}, |
| } |
| } |
| |
| func (s *rootAPIsHandler) AddGroup(apiGroup metav1.APIGroup) { |
| s.lock.Lock() |
| defer s.lock.Unlock() |
| |
| _, alreadyExists := s.apiGroups[apiGroup.Name] |
| |
| s.apiGroups[apiGroup.Name] = apiGroup |
| if !alreadyExists { |
| s.apiGroupNames = append(s.apiGroupNames, apiGroup.Name) |
| } |
| } |
| |
| func (s *rootAPIsHandler) RemoveGroup(groupName string) { |
| s.lock.Lock() |
| defer s.lock.Unlock() |
| |
| delete(s.apiGroups, groupName) |
| for i := range s.apiGroupNames { |
| if s.apiGroupNames[i] == groupName { |
| s.apiGroupNames = append(s.apiGroupNames[:i], s.apiGroupNames[i+1:]...) |
| break |
| } |
| } |
| } |
| |
| func (s *rootAPIsHandler) ServeHTTP(resp http.ResponseWriter, req *http.Request) { |
| s.lock.RLock() |
| defer s.lock.RUnlock() |
| |
| orderedGroups := []metav1.APIGroup{} |
| for _, groupName := range s.apiGroupNames { |
| orderedGroups = append(orderedGroups, s.apiGroups[groupName]) |
| } |
| |
| clientIP := utilnet.GetClientIP(req) |
| serverCIDR := s.addresses.ServerAddressByClientCIDRs(clientIP) |
| groups := make([]metav1.APIGroup, len(orderedGroups)) |
| for i := range orderedGroups { |
| groups[i] = orderedGroups[i] |
| groups[i].ServerAddressByClientCIDRs = serverCIDR |
| } |
| |
| responsewriters.WriteObjectNegotiated(s.serializer, schema.GroupVersion{}, resp, req, http.StatusOK, &metav1.APIGroupList{Groups: groups}) |
| } |
| |
| func (s *rootAPIsHandler) restfulHandle(req *restful.Request, resp *restful.Response) { |
| s.ServeHTTP(resp.ResponseWriter, req.Request) |
| } |
| |
| // WebService returns a webservice serving api group discovery. |
| // Note: during the server runtime apiGroups might change. |
| func (s *rootAPIsHandler) WebService() *restful.WebService { |
| mediaTypes, _ := negotiation.MediaTypesForSerializer(s.serializer) |
| ws := new(restful.WebService) |
| ws.Path(APIGroupPrefix) |
| ws.Doc("get available API versions") |
| ws.Route(ws.GET("/").To(s.restfulHandle). |
| Doc("get available API versions"). |
| Operation("getAPIVersions"). |
| Produces(mediaTypes...). |
| Consumes(mediaTypes...). |
| Writes(metav1.APIGroupList{})) |
| return ws |
| } |