istio.io/istio@v0.0.0-20240520182934-d79c90f27776/pkg/ctrlz/topics/signals.go (about)

     1  // Copyright 2019 Istio Authors
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package topics
    16  
    17  import (
    18  	"net/http"
    19  	"os"
    20  	"syscall"
    21  
    22  	"istio.io/istio/pkg/ctrlz/fw"
    23  	"istio.io/istio/pkg/ctrlz/topics/assets"
    24  )
    25  
    26  type signalsTopic struct{}
    27  
    28  // SignalsTopic returns a ControlZ topic that sends command signals to the process
    29  func SignalsTopic() fw.Topic {
    30  	return signalsTopic{}
    31  }
    32  
    33  func (signalsTopic) Title() string {
    34  	return "Signals"
    35  }
    36  
    37  func (signalsTopic) Prefix() string {
    38  	return "signal"
    39  }
    40  
    41  func (signalsTopic) Activate(context fw.TopicContext) {
    42  	tmpl := assets.ParseTemplate(context.Layout(), "templates/signals.html")
    43  
    44  	_ = context.HTMLRouter().StrictSlash(true).NewRoute().Path("/").HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
    45  		fw.RenderHTML(w, tmpl, nil)
    46  	})
    47  
    48  	_ = context.JSONRouter().StrictSlash(true).NewRoute().Methods("PUT", "POST").Path("/SIGUSR1").HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
    49  		err := syscall.Kill(os.Getpid(), syscall.SIGUSR1)
    50  		if err != nil {
    51  			w.WriteHeader(http.StatusInternalServerError)
    52  			return
    53  		}
    54  		w.WriteHeader(http.StatusAccepted)
    55  	})
    56  }