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// +build !go1.8
// Code generated by "httpsnoop/codegen"; DO NOT EDIT
package httpsnoop
import (
"bufio"
"io"
"net"
"net/http"
)
// HeaderFunc is part of the http.ResponseWriter interface.
type HeaderFunc func() http.Header
// WriteHeaderFunc is part of the http.ResponseWriter interface.
type WriteHeaderFunc func(code int)
// WriteFunc is part of the http.ResponseWriter interface.
type WriteFunc func(b []byte) (int, error)
// FlushFunc is part of the http.Flusher interface.
type FlushFunc func()
// CloseNotifyFunc is part of the http.CloseNotifier interface.
type CloseNotifyFunc func() <-chan bool
// HijackFunc is part of the http.Hijacker interface.
type HijackFunc func() (net.Conn, *bufio.ReadWriter, error)
// ReadFromFunc is part of the io.ReaderFrom interface.
type ReadFromFunc func(src io.Reader) (int64, error)
// Hooks defines a set of method interceptors for methods included in
// http.ResponseWriter as well as some others. You can think of them as
// middleware for the function calls they target. See Wrap for more details.
type Hooks struct {
Header func(HeaderFunc) HeaderFunc
WriteHeader func(WriteHeaderFunc) WriteHeaderFunc
Write func(WriteFunc) WriteFunc
Flush func(FlushFunc) FlushFunc
CloseNotify func(CloseNotifyFunc) CloseNotifyFunc
Hijack func(HijackFunc) HijackFunc
ReadFrom func(ReadFromFunc) ReadFromFunc
}
// Wrap returns a wrapped version of w that provides the exact same interface
// as w. Specifically if w implements any combination of:
//
// - http.Flusher
// - http.CloseNotifier
// - http.Hijacker
// - io.ReaderFrom
//
// The wrapped version will implement the exact same combination. If no hooks
// are set, the wrapped version also behaves exactly as w. Hooks targeting
// methods not supported by w are ignored. Any other hooks will intercept the
// method they target and may modify the call's arguments and/or return values.
// The CaptureMetrics implementation serves as a working example for how the
// hooks can be used.
func Wrap(w http.ResponseWriter, hooks Hooks) http.ResponseWriter {
rw := &rw{w: w, h: hooks}
_, i0 := w.(http.Flusher)
_, i1 := w.(http.CloseNotifier)
_, i2 := w.(http.Hijacker)
_, i3 := w.(io.ReaderFrom)
switch {
// combination 1/16
case !i0 && !i1 && !i2 && !i3:
return struct {
Unwrapper
http.ResponseWriter
}{rw, rw}
// combination 2/16
case !i0 && !i1 && !i2 && i3:
return struct {
Unwrapper
http.ResponseWriter
io.ReaderFrom
}{rw, rw, rw}
// combination 3/16
case !i0 && !i1 && i2 && !i3:
return struct {
Unwrapper
http.ResponseWriter
http.Hijacker
}{rw, rw, rw}
// combination 4/16
case !i0 && !i1 && i2 && i3:
return struct {
Unwrapper
http.ResponseWriter
http.Hijacker
io.ReaderFrom
}{rw, rw, rw, rw}
// combination 5/16
case !i0 && i1 && !i2 && !i3:
return struct {
Unwrapper
http.ResponseWriter
http.CloseNotifier
}{rw, rw, rw}
// combination 6/16
case !i0 && i1 && !i2 && i3:
return struct {
Unwrapper
http.ResponseWriter
http.CloseNotifier
io.ReaderFrom
}{rw, rw, rw, rw}
// combination 7/16
case !i0 && i1 && i2 && !i3:
return struct {
Unwrapper
http.ResponseWriter
http.CloseNotifier
http.Hijacker
}{rw, rw, rw, rw}
// combination 8/16
case !i0 && i1 && i2 && i3:
return struct {
Unwrapper
http.ResponseWriter
http.CloseNotifier
http.Hijacker
io.ReaderFrom
}{rw, rw, rw, rw, rw}
// combination 9/16
case i0 && !i1 && !i2 && !i3:
return struct {
Unwrapper
http.ResponseWriter
http.Flusher
}{rw, rw, rw}
// combination 10/16
case i0 && !i1 && !i2 && i3:
return struct {
Unwrapper
http.ResponseWriter
http.Flusher
io.ReaderFrom
}{rw, rw, rw, rw}
// combination 11/16
case i0 && !i1 && i2 && !i3:
return struct {
Unwrapper
http.ResponseWriter
http.Flusher
http.Hijacker
}{rw, rw, rw, rw}
// combination 12/16
case i0 && !i1 && i2 && i3:
return struct {
Unwrapper
http.ResponseWriter
http.Flusher
http.Hijacker
io.ReaderFrom
}{rw, rw, rw, rw, rw}
// combination 13/16
case i0 && i1 && !i2 && !i3:
return struct {
Unwrapper
http.ResponseWriter
http.Flusher
http.CloseNotifier
}{rw, rw, rw, rw}
// combination 14/16
case i0 && i1 && !i2 && i3:
return struct {
Unwrapper
http.ResponseWriter
http.Flusher
http.CloseNotifier
io.ReaderFrom
}{rw, rw, rw, rw, rw}
// combination 15/16
case i0 && i1 && i2 && !i3:
return struct {
Unwrapper
http.ResponseWriter
http.Flusher
http.CloseNotifier
http.Hijacker
}{rw, rw, rw, rw, rw}
// combination 16/16
case i0 && i1 && i2 && i3:
return struct {
Unwrapper
http.ResponseWriter
http.Flusher
http.CloseNotifier
http.Hijacker
io.ReaderFrom
}{rw, rw, rw, rw, rw, rw}
}
panic("unreachable")
}
type rw struct {
w http.ResponseWriter
h Hooks
}
func (w *rw) Unwrap() http.ResponseWriter {
return w.w
}
func (w *rw) Header() http.Header {
f := w.w.(http.ResponseWriter).Header
if w.h.Header != nil {
f = w.h.Header(f)
}
return f()
}
func (w *rw) WriteHeader(code int) {
f := w.w.(http.ResponseWriter).WriteHeader
if w.h.WriteHeader != nil {
f = w.h.WriteHeader(f)
}
f(code)
}
func (w *rw) Write(b []byte) (int, error) {
f := w.w.(http.ResponseWriter).Write
if w.h.Write != nil {
f = w.h.Write(f)
}
return f(b)
}
func (w *rw) Flush() {
f := w.w.(http.Flusher).Flush
if w.h.Flush != nil {
f = w.h.Flush(f)
}
f()
}
func (w *rw) CloseNotify() <-chan bool {
f := w.w.(http.CloseNotifier).CloseNotify
if w.h.CloseNotify != nil {
f = w.h.CloseNotify(f)
}
return f()
}
func (w *rw) Hijack() (net.Conn, *bufio.ReadWriter, error) {
f := w.w.(http.Hijacker).Hijack
if w.h.Hijack != nil {
f = w.h.Hijack(f)
}
return f()
}
func (w *rw) ReadFrom(src io.Reader) (int64, error) {
f := w.w.(io.ReaderFrom).ReadFrom
if w.h.ReadFrom != nil {
f = w.h.ReadFrom(f)
}
return f(src)
}
type Unwrapper interface {
Unwrap() http.ResponseWriter
}
// Unwrap returns the underlying http.ResponseWriter from within zero or more
// layers of httpsnoop wrappers.
func Unwrap(w http.ResponseWriter) http.ResponseWriter {
if rw, ok := w.(Unwrapper); ok {
// recurse until rw.Unwrap() returns a non-Unwrapper
return Unwrap(rw.Unwrap())
} else {
return w
}
}
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