feat: [networkservices] A new field metadata is added to message .google.cloud.networkservices.v1.LbTrafficExtension (#5414)

* feat: A new field `metadata` is added to message `.google.cloud.networkservices.v1.LbTrafficExtension`
feat: A new field `metadata` is added to message `.google.cloud.networkservices.v1.LbRouteExtension`
docs: update the comments for dep resources

PiperOrigin-RevId: 638948066

Source-Link: googleapis/googleapis@2244fe4

Source-Link: googleapis/googleapis-gen@c5ce682
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packages/google-cloud-networkservices/protos/google/cloud/networkservices/v1/dep.proto

@@ -26,6 +26,7 @@ import "google/longrunning/operations.proto";
 import "google/protobuf/duration.proto";
 import "google/protobuf/empty.proto";
 import "google/protobuf/field_mask.proto";
+import "google/protobuf/struct.proto";
 import "google/protobuf/timestamp.proto";
 
 option csharp_namespace = "Google.Cloud.NetworkServices.V1";
@@ -218,8 +219,7 @@ message ExtensionChain {
     // Required. A Common Expression Language (CEL) expression that is used to
     // match requests for which the extension chain is executed.
     //
-    // For more information, see
-    // [CEL matcher language
+    // For more information, see [CEL matcher language
     // reference](https://cloud.google.com/service-extensions/docs/cel-matcher-language-reference).
     string cel_expression = 1 [(google.api.field_behavior) = REQUIRED];
   }
@@ -255,7 +255,7 @@ message ExtensionChain {
 
     // Optional. A set of events during request or response processing for which
     // this extension is called. This field is required for the
-    // `LbTrafficExtension` resource. It's not relevant for the
+    // `LbTrafficExtension` resource. It must not be set for the
     // `LbRouteExtension` resource.
     repeated EventType supported_events = 4
         [(google.api.field_behavior) = OPTIONAL];
@@ -273,6 +273,7 @@ message ExtensionChain {
     // error. Any subsequent extensions in the extension chain are also
     // executed. When set to `FALSE` or the default setting of `FALSE` is used,
     // one of the following happens:
+    //
     // * If response headers have not been delivered to the downstream client,
     // a generic 500 error is returned to the client. The error response can be
     // tailored by configuring a custom error response in the load balancer.
@@ -341,8 +342,8 @@ message LbTrafficExtension {
   // Optional. Set of labels associated with the `LbTrafficExtension` resource.
   //
   // The format must comply with [the requirements for
-  // labels](https://cloud.google.com/compute/docs/labeling-resources#requirements) for Google Cloud
-  // resources.
+  // labels](https://cloud.google.com/compute/docs/labeling-resources#requirements)
+  // for Google Cloud resources.
   map<string, string> labels = 4 [(google.api.field_behavior) = OPTIONAL];
 
   // Required. A list of references to the forwarding rules to which this
@@ -366,6 +367,16 @@ message LbTrafficExtension {
   // balancer](https://cloud.google.com/load-balancing/docs/backend-service).
   LoadBalancingScheme load_balancing_scheme = 8
       [(google.api.field_behavior) = REQUIRED];
+
+  // Optional. The metadata provided here is included in the
+  // `ProcessingRequest.metadata_context.filter_metadata` map field. The
+  // metadata is available under the key
+  // `com.google.lb_traffic_extension.<resource_name>`.
+  // The following variables are supported in the metadata:
+  //
+  // `{forwarding_rule_id}` - substituted with the forwarding rule's fully
+  //   qualified resource name.
+  google.protobuf.Struct metadata = 10 [(google.api.field_behavior) = OPTIONAL];
 }
 
 // Message for requesting list of `LbTrafficExtension` resources.
@@ -459,13 +470,13 @@ message CreateLbTrafficExtensionRequest {
 
 // Message for updating a `LbTrafficExtension` resource.
 message UpdateLbTrafficExtensionRequest {
-  // Required. Used to specify the fields to be overwritten in the
+  // Optional. Used to specify the fields to be overwritten in the
   // `LbTrafficExtension` resource by the update.
   // The fields specified in the update_mask are relative to the resource, not
   // the full request. A field is overwritten if it is in the mask. If the
   // user does not specify a mask, then all fields are overwritten.
   google.protobuf.FieldMask update_mask = 1
-      [(google.api.field_behavior) = REQUIRED];
+      [(google.api.field_behavior) = OPTIONAL];
 
   // Required. `LbTrafficExtension` resource being updated.
   LbTrafficExtension lb_traffic_extension = 2
@@ -553,8 +564,8 @@ message LbRouteExtension {
   // Optional. Set of labels associated with the `LbRouteExtension` resource.
   //
   // The format must comply with [the requirements for
-  // labels](https://cloud.google.com/compute/docs/labeling-resources#requirements) for Google Cloud
-  // resources.
+  // labels](https://cloud.google.com/compute/docs/labeling-resources#requirements)
+  // for Google Cloud resources.
   map<string, string> labels = 4 [(google.api.field_behavior) = OPTIONAL];
 
   // Required. A list of references to the forwarding rules to which this
@@ -578,6 +589,17 @@ message LbRouteExtension {
   // balancer](https://cloud.google.com/load-balancing/docs/backend-service).
   LoadBalancingScheme load_balancing_scheme = 8
       [(google.api.field_behavior) = REQUIRED];
+
+  // Optional. The metadata provided here is included as part of the
+  // `metadata_context` (of type `google.protobuf.Struct`) in the
+  // `ProcessingRequest` message sent to the extension
+  // server. The metadata is available under the namespace
+  // `com.google.lb_route_extension.<resource_name>`.
+  // The following variables are supported in the metadata Struct:
+  //
+  // `{forwarding_rule_id}` - substituted with the forwarding rule's fully
+  //   qualified resource name.
+  google.protobuf.Struct metadata = 10 [(google.api.field_behavior) = OPTIONAL];
 }
 
 // Message for requesting list of `LbRouteExtension` resources.
@@ -671,13 +693,13 @@ message CreateLbRouteExtensionRequest {
 
 // Message for updating a `LbRouteExtension` resource.
 message UpdateLbRouteExtensionRequest {
-  // Required. Used to specify the fields to be overwritten in the
+  // Optional. Used to specify the fields to be overwritten in the
   // `LbRouteExtension` resource by the update.
   // The fields specified in the update_mask are relative to the resource, not
   // the full request. A field is overwritten if it is in the mask. If the
   // user does not specify a mask, then all fields are overwritten.
   google.protobuf.FieldMask update_mask = 1
-      [(google.api.field_behavior) = REQUIRED];
+      [(google.api.field_behavior) = OPTIONAL];
 
   // Required. `LbRouteExtension` resource being updated.
   LbRouteExtension lb_route_extension = 2