From 1ab40cd213c3904e3f0e2e392aea9e1511f9f830 Mon Sep 17 00:00:00 2001
From: "hubert.siwik" <hubert.siwik@vodeno.com>
Date: Tue, 9 Jul 2024 13:28:27 +0200
Subject: [PATCH] Header getter/setter should be case in-sensitive

---
 ftwhttp/header.go      | 22 ++++++++++++++++------
 ftwhttp/header_test.go | 12 ++++++++++++
 2 files changed, 28 insertions(+), 6 deletions(-)

diff --git a/ftwhttp/header.go b/ftwhttp/header.go
index cb593321..59b03dd3 100644
--- a/ftwhttp/header.go
+++ b/ftwhttp/header.go
@@ -6,6 +6,7 @@ package ftwhttp
 import (
 	"bytes"
 	"io"
+	"net/textproto"
 	"sort"
 
 	"github.com/rs/zerolog/log"
@@ -34,7 +35,9 @@ func (w stringWriter) WriteString(s string) (n int, err error) {
 
 // Add adds the key, value pair to the header.
 // It appends to any existing values associated with key.
+// The key is case in-sensitive
 func (h Header) Add(key, value string) {
+	key = canonicalHeaderKey(key)
 	if h.Get(key) == "" {
 		h.Set(key, value)
 	}
@@ -43,35 +46,37 @@ func (h Header) Add(key, value string) {
 // Set sets the header entries associated with key to
 // the single element value. It replaces any existing
 // values associated with key.
+// The key is case in-sensitive
 func (h Header) Set(key, value string) {
-	h[key] = value
+	h[canonicalHeaderKey(key)] = value
 }
 
 // Get gets the first value associated with the given key.
-// It is case insensitive;
 // If there are no values associated with the key, Get returns "".
+// The key is case in-sensitive
 func (h Header) Get(key string) string {
 	if h == nil {
 		return ""
 	}
-	v := h[key]
+	v := h[canonicalHeaderKey(key)]
 
 	return v
 }
 
 // Value returns the value associated with the given key.
-// It is case insensitive;
+// The key is case in-sensitive
 func (h Header) Value(key string) string {
 	if h == nil {
 		return ""
 	}
 
-	return h[key]
+	return h[canonicalHeaderKey(key)]
 }
 
 // Del deletes the value associated with key.
+// The key is case in-sensitive
 func (h Header) Del(key string) {
-	delete(h, key)
+	delete(h, canonicalHeaderKey(key))
 }
 
 // Write writes a header in wire format.
@@ -138,3 +143,8 @@ func (h Header) getSortedHeadersByName() []string {
 
 	return keys
 }
+
+// canonicalHeaderKey transform given to the canonical form
+func canonicalHeaderKey(key string) string {
+	return textproto.CanonicalMIMEHeaderKey(key)
+}
diff --git a/ftwhttp/header_test.go b/ftwhttp/header_test.go
index 780c1d4f..0c1b926f 100644
--- a/ftwhttp/header_test.go
+++ b/ftwhttp/header_test.go
@@ -111,6 +111,11 @@ func (s *headerTestSuite) TestHeaderSetGet() {
 	h.Add("Other", "Value")
 	value := h.Get("Other")
 	s.Equalf("Value", value, "got: %s, want: %s\n", value, "Value")
+
+	// Case in-sensitive
+	h.Add("camel-Header", "Value")
+	value = h.Get("Camel-header")
+	s.Equalf("Value", value, "got: %s, want: %s\n", value, "Value")
 }
 
 func (s *headerTestSuite) TestHeaderDel() {
@@ -124,6 +129,13 @@ func (s *headerTestSuite) TestHeaderDel() {
 			s.Equalf("", value, "#%d: got: %s, want: %s\n", i, value, "")
 		}
 	}
+
+	// Case in-sensitive
+	h := Header{}
+	h.Add("content-Type", "Value")
+	h.Del("Content-type")
+	value := h.Get("Content-Type")
+	s.Equalf("", value, "#case: got: %s, want: %s\n", value, "")
 }
 
 func (s *headerTestSuite) TestHeaderClone() {