| /* |
| 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 filters |
| |
| import ( |
| "errors" |
| "net/http" |
| |
| utilwaitgroup "k8s.io/apimachinery/pkg/util/waitgroup" |
| "k8s.io/apiserver/pkg/endpoints/handlers/responsewriters" |
| apirequest "k8s.io/apiserver/pkg/endpoints/request" |
| ) |
| |
| // WithWaitGroup adds all non long-running requests to wait group, which is used for graceful shutdown. |
| func WithWaitGroup(handler http.Handler, longRunning apirequest.LongRunningRequestCheck, wg *utilwaitgroup.SafeWaitGroup) http.Handler { |
| return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) { |
| ctx := req.Context() |
| requestInfo, ok := apirequest.RequestInfoFrom(ctx) |
| if !ok { |
| // if this happens, the handler chain isn't setup correctly because there is no request info |
| responsewriters.InternalError(w, req, errors.New("no RequestInfo found in the context")) |
| return |
| } |
| |
| if !longRunning(req, requestInfo) { |
| if err := wg.Add(1); err != nil { |
| http.Error(w, "apiserver is shutting down.", http.StatusInternalServerError) |
| return |
| } |
| defer wg.Done() |
| } |
| |
| handler.ServeHTTP(w, req) |
| }) |
| } |