100 lines
2.5 KiB
Go
100 lines
2.5 KiB
Go
|
package negroni
|
||
|
|
||
|
import (
|
||
|
"bufio"
|
||
|
"fmt"
|
||
|
"net"
|
||
|
"net/http"
|
||
|
)
|
||
|
|
||
|
// ResponseWriter is a wrapper around http.ResponseWriter that provides extra information about
|
||
|
// the response. It is recommended that middleware handlers use this construct to wrap a responsewriter
|
||
|
// if the functionality calls for it.
|
||
|
type ResponseWriter interface {
|
||
|
http.ResponseWriter
|
||
|
http.Flusher
|
||
|
// Status returns the status code of the response or 200 if the response has
|
||
|
// not been written (as this is the default response code in net/http)
|
||
|
Status() int
|
||
|
// Written returns whether or not the ResponseWriter has been written.
|
||
|
Written() bool
|
||
|
// Size returns the size of the response body.
|
||
|
Size() int
|
||
|
// Before allows for a function to be called before the ResponseWriter has been written to. This is
|
||
|
// useful for setting headers or any other operations that must happen before a response has been written.
|
||
|
Before(func(ResponseWriter))
|
||
|
}
|
||
|
|
||
|
type beforeFunc func(ResponseWriter)
|
||
|
|
||
|
// NewResponseWriter creates a ResponseWriter that wraps an http.ResponseWriter
|
||
|
func NewResponseWriter(rw http.ResponseWriter) ResponseWriter {
|
||
|
return &responseWriter{
|
||
|
ResponseWriter: rw,
|
||
|
}
|
||
|
}
|
||
|
|
||
|
type responseWriter struct {
|
||
|
http.ResponseWriter
|
||
|
status int
|
||
|
size int
|
||
|
beforeFuncs []beforeFunc
|
||
|
}
|
||
|
|
||
|
func (rw *responseWriter) WriteHeader(s int) {
|
||
|
rw.status = s
|
||
|
rw.callBefore()
|
||
|
rw.ResponseWriter.WriteHeader(s)
|
||
|
}
|
||
|
|
||
|
func (rw *responseWriter) Write(b []byte) (int, error) {
|
||
|
if !rw.Written() {
|
||
|
// The status will be StatusOK if WriteHeader has not been called yet
|
||
|
rw.WriteHeader(http.StatusOK)
|
||
|
}
|
||
|
size, err := rw.ResponseWriter.Write(b)
|
||
|
rw.size += size
|
||
|
return size, err
|
||
|
}
|
||
|
|
||
|
func (rw *responseWriter) Status() int {
|
||
|
return rw.status
|
||
|
}
|
||
|
|
||
|
func (rw *responseWriter) Size() int {
|
||
|
return rw.size
|
||
|
}
|
||
|
|
||
|
func (rw *responseWriter) Written() bool {
|
||
|
return rw.status != 0
|
||
|
}
|
||
|
|
||
|
func (rw *responseWriter) Before(before func(ResponseWriter)) {
|
||
|
rw.beforeFuncs = append(rw.beforeFuncs, before)
|
||
|
}
|
||
|
|
||
|
func (rw *responseWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) {
|
||
|
hijacker, ok := rw.ResponseWriter.(http.Hijacker)
|
||
|
if !ok {
|
||
|
return nil, nil, fmt.Errorf("the ResponseWriter doesn't support the Hijacker interface")
|
||
|
}
|
||
|
return hijacker.Hijack()
|
||
|
}
|
||
|
|
||
|
func (rw *responseWriter) CloseNotify() <-chan bool {
|
||
|
return rw.ResponseWriter.(http.CloseNotifier).CloseNotify()
|
||
|
}
|
||
|
|
||
|
func (rw *responseWriter) callBefore() {
|
||
|
for i := len(rw.beforeFuncs) - 1; i >= 0; i-- {
|
||
|
rw.beforeFuncs[i](rw)
|
||
|
}
|
||
|
}
|
||
|
|
||
|
func (rw *responseWriter) Flush() {
|
||
|
flusher, ok := rw.ResponseWriter.(http.Flusher)
|
||
|
if ok {
|
||
|
flusher.Flush()
|
||
|
}
|
||
|
}
|