in core/response.go [63:77]
func (r *ProxyResponseWriter) Write(body []byte) (int, error) {
if r.status == defaultStatusCode {
r.status = http.StatusOK
}
// if the content type header is not set when we write the body we try to
// detect one and set it by default. If the content type cannot be detected
// it is automatically set to "application/octet-stream" by the
// DetectContentType method
if r.Header().Get(contentTypeHeaderKey) == "" {
r.Header().Add(contentTypeHeaderKey, http.DetectContentType(body))
}
return (&r.body).Write(body)
}