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 fw
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import (
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	"bytes"
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	"encoding/json"
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	"fmt"
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	"html/template"
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	"net/http"
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)
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// RenderError outputs an error message
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func RenderError(w http.ResponseWriter, statusCode int, err error) {
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	w.WriteHeader(statusCode)
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	w.Header().Set("Content-Type", "text/plain; charset=utf-8")
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	_, _ = fmt.Fprintf(w, "%v", err)
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}
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// RenderHTML executes the given template, sending the output to the supplied response writer
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func RenderHTML(w http.ResponseWriter, t *template.Template, data any) {
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	b := &bytes.Buffer{}
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	if err := t.Execute(b, data); err != nil {
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		RenderError(w, http.StatusInternalServerError, err)
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		return
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	}
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	w.WriteHeader(http.StatusOK)
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	w.Header().Set("Content-Type", "text/html; charset=utf-8")
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	_, _ = b.WriteTo(w)
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}
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// RenderJSON outputs the given data as JSON
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func RenderJSON(w http.ResponseWriter, statusCode int, data any) {
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	w.WriteHeader(statusCode)
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	w.Header().Set("Content-Type", "application/json; charset=utf-8")
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	if err := json.NewEncoder(w).Encode(data); err != nil {
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		RenderError(w, http.StatusInternalServerError, err)
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	}
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}
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