feat: add PeekKeys and PeekTrailerKeys (#1405)

* feat: add PeekKeys and PeekTrailerKeys

* Improve warning

Co-authored-by: Erik Dubbelboer <erik@dubbelboer.com>

1 files changed, 51 insertions, 1 deletions

diff --git a/header.go b/header.go
index 89499a3..fe4f669 100644
--- a/header.go
+++ b/header.go
@@ -1801,6 +1801,7 @@ func (h *RequestHeader) peek(key []byte) []byte {
 //
 // The returned value is valid until the request is released,
 // either though ReleaseRequest or your request handler returning.
+// Any future calls to the Peek* will modify the returned value.
 // Do not store references to returned value. Make copies instead.
 func (h *RequestHeader) PeekAll(key string) [][]byte {
 	k := getHeaderKeyBytes(&h.bufKV, key, h.disableNormalizing)
@@ -1847,7 +1848,8 @@ func (h *RequestHeader) peekAll(key []byte) [][]byte {
 // PeekAll returns all header value for the given key.
 //
 // The returned value is valid until the request is released,
-// either though ReleaseRequest or your request handler returning.
+// either though ReleaseResponse or your request handler returning.
+// Any future calls to the Peek* will modify the returned value.
 // Do not store references to returned value. Make copies instead.
 func (h *ResponseHeader) PeekAll(key string) [][]byte {
 	k := getHeaderKeyBytes(&h.bufKV, key, h.disableNormalizing)
@@ -1887,6 +1889,54 @@ func (h *ResponseHeader) peekAll(key []byte) [][]byte {
 	return h.mulHeader
 }
 
+// PeekKeys return all header keys.
+//
+// The returned value is valid until the request is released,
+// either though ReleaseRequest or your request handler returning.
+// Any future calls to the Peek* will modify the returned value.
+// Do not store references to returned value. Make copies instead.
+func (h *RequestHeader) PeekKeys() [][]byte {
+	h.mulHeader = h.mulHeader[:0]
+	h.mulHeader = peekArgsKeys(h.mulHeader, h.h)
+	return h.mulHeader
+}
+
+// PeekTrailerKeys return all trailer keys.
+//
+// The returned value is valid until the request is released,
+// either though ReleaseRequest or your request handler returning.
+// Any future calls to the Peek* will modify the returned value.
+// Do not store references to returned value. Make copies instead.
+func (h *RequestHeader) PeekTrailerKeys() [][]byte {
+	h.mulHeader = h.mulHeader[:0]
+	h.mulHeader = peekArgsKeys(h.mulHeader, h.trailer)
+	return h.mulHeader
+}
+
+// PeekKeys return all header keys.
+//
+// The returned value is valid until the request is released,
+// either though ReleaseResponse or your request handler returning.
+// Any future calls to the Peek* will modify the returned value.
+// Do not store references to returned value. Make copies instead.
+func (h *ResponseHeader) PeekKeys() [][]byte {
+	h.mulHeader = h.mulHeader[:0]
+	h.mulHeader = peekArgsKeys(h.mulHeader, h.h)
+	return h.mulHeader
+}
+
+// PeekTrailerKeys return all trailer keys.
+//
+// The returned value is valid until the request is released,
+// either though ReleaseResponse or your request handler returning.
+// Any future calls to the Peek* will modify the returned value.
+// Do not store references to returned value. Make copies instead.
+func (h *ResponseHeader) PeekTrailerKeys() [][]byte {
+	h.mulHeader = h.mulHeader[:0]
+	h.mulHeader = peekArgsKeys(h.mulHeader, h.trailer)
+	return h.mulHeader
+}
+
 // Cookie returns cookie for the given key.
 func (h *RequestHeader) Cookie(key string) []byte {
 	h.collectCookies()