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package httperr
// Note: The writer proxies in this file are a heavily modified version of
// code bearing the following message:
//
// Copyright (c) 2014, 2015, 2016 Carl Jackson (carl@avtok.com)
//
// MIT License
//
// Permission is hereby granted, free of charge, to any person obtaining a copy of
// this software and associated documentation files (the "Software"), to deal in
// the Software without restriction, including without limitation the rights to
// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
// the Software, and to permit persons to whom the Software is furnished to do so,
// subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
// FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
// COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
// IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
// CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
import (
"bufio"
"bytes"
"io/ioutil"
"net"
"net/http"
)
// wrapWriter wraps an http.ResponseWriter, returning a proxy that
// tracks the response.
func wrapWriter(w http.ResponseWriter) (*basicWriter, http.ResponseWriter) {
_, isCloseNotifier := w.(http.CloseNotifier)
_, isFlusher := w.(http.Flusher)
_, isHijacker := w.(http.Hijacker)
bw := basicWriter{ResponseWriter: w}
if isCloseNotifier && isFlusher && isHijacker {
rv := fancyWriter{bw}
return &rv.basicWriter, &rv
}
if isFlusher {
rv := flushWriter{bw}
return &rv.basicWriter, &rv
}
return &bw, &bw
}
type basicWriter struct {
http.ResponseWriter
statusCode int
copy *http.Response
body *bytes.Buffer
}
func (b *basicWriter) WriteHeader(code int) {
b.statusCode = code
if code < 400 {
b.ResponseWriter.WriteHeader(code)
return
}
b.copy = &http.Response{
StatusCode: code,
Header: b.ResponseWriter.Header(),
}
}
func (b *basicWriter) Write(buf []byte) (int, error) {
if b.copy == nil {
return b.ResponseWriter.Write(buf)
}
if b.body == nil {
b.body = &bytes.Buffer{}
b.copy.Body = ioutil.NopCloser(b.body)
}
return b.body.Write(buf)
}
type fancyWriter struct {
basicWriter
}
func (f *fancyWriter) CloseNotify() <-chan bool {
cn := f.basicWriter.ResponseWriter.(http.CloseNotifier)
return cn.CloseNotify()
}
func (f *fancyWriter) Flush() {
fl := f.basicWriter.ResponseWriter.(http.Flusher)
fl.Flush()
}
func (f *fancyWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) {
hj := f.basicWriter.ResponseWriter.(http.Hijacker)
return hj.Hijack()
}
var _ http.CloseNotifier = &fancyWriter{}
var _ http.Flusher = &fancyWriter{}
var _ http.Hijacker = &fancyWriter{}
type flushWriter struct {
basicWriter
}
func (f *flushWriter) Flush() {
fl := f.basicWriter.ResponseWriter.(http.Flusher)
fl.Flush()
}
var _ http.Flusher = &flushWriter{}
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