Add websocket support (#962)

* Add websocket support

* Ignore resource not found error in conformance cleanup make command

* Review feedback

Author: ciarams87

conformance/Makefile

@@ -89,7 +89,7 @@ uninstall-nkg: uninstall-k8s-components undo-manifests-update ## Uninstall NKG o
 
 .PHONY: uninstall-k8s-components
 uninstall-k8s-components: ## Uninstall installed components on configured kind cluster
-	kubectl delete -f $(NKG_MANIFEST)
+	-kubectl delete -f $(NKG_MANIFEST)
 	./scripts/uninstall-gateway.sh $(GW_API_VERSION)
 	kubectl delete clusterrole nginx-gateway-provisioner
 	kubectl delete clusterrolebinding nginx-gateway-provisioner

internal/mode/static/nginx/config/maps_template.go

@@ -17,4 +17,11 @@ map $http_host $gw_api_compliant_host {
     '' $host;
     default $http_host;
 }
+
+# Set $connection_header variable to upgrade when the $http_upgrade header is set, otherwise, set it to close. This
+# allows support for websocket connections. See https://nginx.org/en/docs/http/websocket.html.
+map $http_upgrade $connection_upgrade {
+    default upgrade;
+    '' close;
+}
 `

internal/mode/static/nginx/config/maps_test.go

@@ -85,6 +85,7 @@ func TestExecuteMaps(t *testing.T) {
 		"~.* ${http_my_second_add_header},;":                                  1,
 		"map ${http_my_set_header} $my_set_header_header_var {":               0,
 		"map $http_host $gw_api_compliant_host {":                             1,
+		"map $http_upgrade $connection_upgrade {":                             1,
 	}
 
 	maps := string(executeMaps(conf))

internal/mode/static/nginx/config/servers_template.go

@@ -51,6 +51,9 @@ server {
         proxy_set_header {{ $h.Name }} "{{ $h.Value }}";
             {{- end }}
         proxy_set_header Host $gw_api_compliant_host;
+        proxy_http_version 1.1;
+        proxy_set_header Upgrade $http_upgrade;
+        proxy_set_header Connection $connection_upgrade;
         proxy_pass {{ $l.ProxyPass }}$request_uri;
         {{- end }}
     }

internal/mode/static/nginx/config/validation/common.go

@@ -52,19 +52,25 @@ func validateEscapedStringNoVarExpansion(value string, examples []string) error
 }
 
 const (
-	invalidHostHeaderErrMsg string = "redefining the Host request header is not supported"
-	maxHeaderLength         int    = 256
+	invalidHeadersErrMsg string = "unsupported header name configured, unsupported names are: "
+	maxHeaderLength      int    = 256
 )
 
+var invalidHeaders = map[string]struct{}{
+	"host":       {},
+	"connection": {},
+	"upgrade":    {},
+}
+
 func validateHeaderName(name string) error {
 	if len(name) > maxHeaderLength {
 		return errors.New(k8svalidation.MaxLenError(maxHeaderLength))
 	}
 	if msg := k8svalidation.IsHTTPHeaderName(name); msg != nil {
 		return errors.New(msg[0])
 	}
-	if strings.ToLower(name) == "host" {
-		return errors.New(invalidHostHeaderErrMsg)
+	if valid, invalidHeadersAsStrings := validateNoUnsupportedValues(strings.ToLower(name), invalidHeaders); !valid {
+		return errors.New(invalidHeadersErrMsg + strings.Join(invalidHeadersAsStrings, ", "))
 	}
 	return nil
 }

internal/mode/static/nginx/config/validation/common_test.go

@@ -64,6 +64,8 @@ func TestValidateValidHeaderName(t *testing.T) {
 		`$test`,
 		"Host",
 		"host",
+		"connection",
+		"upgrade",
 		"my-header[]",
 		"my-header&",
 		strings.Repeat("very-long-header", 16)+"1",

internal/mode/static/nginx/config/validation/framework.go

@@ -20,6 +20,16 @@ func validateInSupportedValues[T configValue](
 	return false, getSortedKeysAsString(supportedValues)
 }
 
+func validateNoUnsupportedValues[T configValue](
+	value T,
+	unsupportedValues map[T]struct{},
+) (valid bool, unsupportedValuesAsStrings []string) {
+	if _, exist := unsupportedValues[value]; exist {
+		return false, getSortedKeysAsString(unsupportedValues)
+	}
+	return true, nil
+}
+
 func getSortedKeysAsString[T configValue](m map[T]struct{}) []string {
 	keysAsString := make([]string, 0, len(m))
 

internal/mode/static/nginx/config/validation/framework_test.go

@@ -99,6 +99,34 @@ func TestValidateInSupportedValues(t *testing.T) {
 	)
 }
 
+func TestValidateNoUnsupportedValues(t *testing.T) {
+	unsupportedValues := map[string]struct{}{
+		"badvalue1": {},
+		"badvalue2": {},
+		"badvalue3": {},
+	}
+
+	validator := func(value string) (bool, []string) {
+		return validateNoUnsupportedValues(value, unsupportedValues)
+	}
+
+	testValidValuesForSupportedValuesValidator(
+		t,
+		validator,
+		"value1",
+		"value2",
+		"value3",
+	)
+	testInvalidValuesForSupportedValuesValidator(
+		t,
+		validator,
+		unsupportedValues,
+		"badvalue1",
+		"badvalue2",
+		"badvalue3",
+	)
+}
+
 func TestGetSortedKeysAsString(t *testing.T) {
 	values := map[string]struct{}{
 		"value3": {},

internal/mode/static/nginx/config/validation/http_filters_test.go

@@ -74,7 +74,7 @@ func TestValidateRequestHeaderName(t *testing.T) {
 		t,
 		validator.ValidateRequestHeaderName,
 		"Content-Encoding",
-		"Connection",
+		"MyBespokeHeader",
 	)
 
 	testInvalidValuesForSimpleValidator(t, validator.ValidateRequestHeaderName, "$Content-Encoding")

internal/mode/static/state/dataplane/configuration_test.go

@@ -1609,8 +1609,8 @@ func TestCreateFilters(t *testing.T) {
 		RequestHeaderModifier: &v1beta1.HTTPHeaderFilter{
 			Set: []v1beta1.HTTPHeader{
 				{
-					Name:  "Connection",
-					Value: "close",
+					Name:  "MyBespokeHeader",
+					Value: "my-value",
 				},
 			},
 		},