istio

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// Copyright Istio Authors
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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//     http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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// Package topics defines several canonical ControlZ topics.
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package topics
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import (
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	"net/http"
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	"runtime"
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	"istio.io/istio/pkg/ctrlz/fw"
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	"istio.io/istio/pkg/ctrlz/topics/assets"
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)
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type memTopic struct{}
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// MemTopic returns a ControlZ topic that allows visualization of process memory usage.
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func MemTopic() fw.Topic {
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	return memTopic{}
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}
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func (memTopic) Title() string {
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	return "Memory Usage"
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}
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func (memTopic) Prefix() string {
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	return "mem"
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}
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func (memTopic) Activate(context fw.TopicContext) {
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	tmpl := assets.ParseTemplate(context.Layout(), "templates/mem.html")
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	_ = context.HTMLRouter().StrictSlash(true).NewRoute().Path("/").HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
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		ms := &runtime.MemStats{}
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		runtime.ReadMemStats(ms)
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		fw.RenderHTML(w, tmpl, ms)
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	})
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	_ = context.JSONRouter().StrictSlash(true).NewRoute().Methods("GET").Path("/").HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
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		ms := &runtime.MemStats{}
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		runtime.ReadMemStats(ms)
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		fw.RenderJSON(w, http.StatusOK, ms)
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	})
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	_ = context.JSONRouter().StrictSlash(true).NewRoute().Methods("PUT").Path("/forcecollection").HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
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		runtime.GC()
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		w.WriteHeader(http.StatusAccepted)
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	})
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}
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