/
response_writer.go
55 lines (48 loc) · 1.34 KB
/
response_writer.go
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package sandwich
import (
"bufio"
"fmt"
"net"
"net/http"
)
// WrapResponseWriter creates a ResponseWriter and returns it as both an
// http.ResponseWriter and a *ResponseWriter. The double return is redundant
// for native Go code, but is a necessary hint to the dependency injection.
func WrapResponseWriter(w http.ResponseWriter) (http.ResponseWriter, *ResponseWriter) {
rw := &ResponseWriter{w, 0, 0}
return rw, rw
}
// ResponseWriter wraps http.ResponseWriter to add tracking of the response size
// and response code.
type ResponseWriter struct {
http.ResponseWriter
Size int // The size of the response written so far, in bytes.
Code int // The status code of the response, or 0 if not written yet.
}
func (w *ResponseWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) {
hijacker, ok := w.ResponseWriter.(http.Hijacker)
if !ok {
return nil, nil, fmt.Errorf("the ResponseWriter doesn't support the Hijacker interface")
}
return hijacker.Hijack()
}
func (w *ResponseWriter) Flush() {
flusher, ok := w.ResponseWriter.(http.Flusher)
if ok {
flusher.Flush()
}
}
func (w *ResponseWriter) WriteHeader(code int) {
if w.Code == 0 {
w.Code = code
}
w.ResponseWriter.WriteHeader(code)
}
func (w *ResponseWriter) Write(p []byte) (int, error) {
if w.Code == 0 {
w.Code = 200
}
n, err := w.ResponseWriter.Write(p)
w.Size += n
return n, err
}