Add GetAllHeaders method to golang HTTP filter

contrib/golang/common/go/api/type.go

@@ -131,6 +131,9 @@ type HeaderMap interface {
 
 	// RangeWithCopy calls f sequentially for each key and value copied from the map.
 	RangeWithCopy(f func(key, value string) bool)
+
+	// GetAllHeaders returns all the headers.
+	GetAllHeaders() map[string][]string
 }
 
 type RequestHeaderMap interface {

contrib/golang/filters/http/source/go/pkg/http/type.go

@@ -155,6 +155,14 @@ func (h *requestOrResponseHeaderMapImpl) RangeWithCopy(f func(key, value string)
 	}
 }
 
+func (h *requestOrResponseHeaderMapImpl) GetAllHeaders() map[string][]string {
+	h.mutex.Lock()
+	defer h.mutex.Unlock()
+	h.initHeaders()
+	copied_headers := h.headers
+	return copied_headers
+}
+
 // api.RequestHeaderMap
 type requestHeaderMapImpl struct {
 	requestOrResponseHeaderMapImpl
@@ -318,6 +326,14 @@ func (h *requestOrResponseTrailerMapImpl) RangeWithCopy(f func(key, value string
 	}
 }
 
+func (h *requestOrResponseTrailerMapImpl) GetAllHeaders() map[string][]string {
+	h.mutex.Lock()
+	defer h.mutex.Unlock()
+	h.initTrailers()
+	copied_headers := h.headers
+	return copied_headers
+}
+
 // api.RequestTrailerMap
 type requestTrailerMapImpl struct {
 	requestOrResponseTrailerMapImpl