OPENAPI: the rewrite header key formatting is wrong in code

config/paths.go

@@ -12,9 +12,17 @@ import (
 )
 
 const (
-	RewriteIdHeader = "RewriteId"
+	PascalCaseRewriteIdHeader = "Rewriteid"
+	SnakeCaseRewriteIdHeader  = "Rewrite_id"
+	KebabCaseRewriteIdHeader  = "Rewrite-Id"
 )
 
+var rewriteIdHeaders = []string{
+	PascalCaseRewriteIdHeader,
+	SnakeCaseRewriteIdHeader,
+	KebabCaseRewriteIdHeader,
+}
+
 type PathRewrite struct {
 	RewrittenPath     string
 	PathConfiguration *shared.WiretapPathConfig
@@ -94,13 +102,54 @@ func rewriteTaget(path string, pathConfig *shared.WiretapPathConfig, configurati
 	}
 }
 
+func getRewriteIdHeaderValues(req *http.Request) ([]string, bool) {
+
+	// Let's first try to get the header with expected key names
+	for _, possibleHeaderKey := range rewriteIdHeaders {
+
+		if rewriteIdHeaderValues, ok := req.Header[possibleHeaderKey]; ok {
+			return rewriteIdHeaderValues, true
+		}
+
+		if rewriteIdHeaderValues, ok := req.Header[strings.ToLower(possibleHeaderKey)]; ok {
+			return rewriteIdHeaderValues, true
+		}
+
+	}
+
+	// Let's now try to ignore case ; this may produce collisions if a user has two headers with similar keys,
+	// but different capitalization. This is okay, as this is a last ditch effort to find any possible match
+	loweredHeaders := map[string][]string{}
+
+	for headerKey, headerValues := range req.Header {
+		loweredKey := strings.ToLower(headerKey)
+
+		if _, ok := loweredHeaders[loweredKey]; ok {
+			loweredHeaders[loweredKey] = append(loweredHeaders[loweredKey], headerValues...)
+		} else {
+			loweredHeaders[loweredKey] = headerValues
+		}
+
+	}
+
+	for _, possibleHeaderKey := range rewriteIdHeaders {
+
+		if rewriteIdHeaderValues, ok := loweredHeaders[strings.ToLower(possibleHeaderKey)]; ok {
+			return rewriteIdHeaderValues, true
+		}
+
+	}
+
+	return []string{}, false
+}
+
 func FindPathWithRewriteId(paths []*shared.WiretapPathConfig, req *http.Request) *shared.WiretapPathConfig {
 
 	if req == nil {
 		return nil
 	}
 
-	if rewriteIdHeaderValues, ok := req.Header[RewriteIdHeader]; ok {
+	if rewriteIdHeaderValues, ok := getRewriteIdHeaderValues(req); ok {
 		for _, pathRewriteConfig := range paths {
 
 			// Iterate through header values - since it's a multi-value field

config/paths_test.go

@@ -494,3 +494,96 @@ func TestValidationAllowList_NoPathsRegistered(t *testing.T) {
 	assert.False(t, ignore)
 
 }
+
+func TestGetRewriteHeaderValues(t *testing.T) {
+
+	expectedValue := []string{"ExpectedValue"}
+
+	requestList := []*http.Request{
+		{
+			Header: http.Header{
+				"Rewriteid":    expectedValue,
+				"Other-Header": []string{"another header"},
+				"other-header": []string{"another another header"},
+			},
+		},
+		{
+			Header: http.Header{
+				"Rewrite-Id":   expectedValue,
+				"Other-Header": []string{"another header"},
+				"other-header": []string{"another another header"},
+			},
+		},
+		{
+			Header: http.Header{
+				"Rewrite_id":   expectedValue,
+				"Other-Header": []string{"another header"},
+				"other-header": []string{"another another header"},
+			},
+		},
+		{
+			Header: http.Header{
+				"RewriteId":    expectedValue,
+				"Other-Header": []string{"another header"},
+				"other-header": []string{"another another header"},
+			},
+		},
+		{
+			Header: http.Header{
+				"RewrIte-Id":   expectedValue,
+				"Other-Header": []string{"another header"},
+				"other-header": []string{"another another header"},
+			},
+		},
+		{
+			Header: http.Header{
+				"rewriteid":    expectedValue,
+				"Other-Header": []string{"another header"},
+				"other-header": []string{"another another header"},
+			},
+		},
+		{
+			Header: http.Header{
+				"rewrite-id":   expectedValue,
+				"Other-Header": []string{"another header"},
+				"other-header": []string{"another another header"},
+			},
+		},
+		{
+			Header: http.Header{
+				"rewrite_id":   expectedValue,
+				"Other-Header": []string{"another header"},
+				"other-header": []string{"another another header"},
+			},
+		},
+	}
+
+	for _, request := range requestList {
+		actualValue, found := getRewriteIdHeaderValues(request)
+		assert.Equal(t, expectedValue, actualValue)
+		assert.True(t, found)
+	}
+
+}
+
+func TestGetRewriteHeaderValues_MissingHeader(t *testing.T) {
+
+	requestList := []*http.Request{
+		{
+			Header: http.Header{
+				"Other-Header": []string{"another header"},
+				"other-header": []string{"another another header"},
+			},
+		},
+		{
+			Header: http.Header{},
+		},
+	}
+
+	for _, request := range requestList {
+		actualValue, found := getRewriteIdHeaderValues(request)
+		assert.Equal(t, []string{}, actualValue)
+		assert.False(t, found)
+	}
+
+}