Warnings are predefined with a specific code and referenced when adding them to the response.

Author: talanknight

internal/gen/controller/api/warning.pb.go

@@ -32,14 +32,18 @@ message BehaviorWarning {
   string warning = 1;
 }
 
-// Warning is returned by the JSON API when a warning occurs.
+// A warning in the Boundary system.
 message Warning {
-  // Request-field-specific warning details.
-  repeated FieldWarning request_fields = 1 [json_name = "request_fields"];
-
-  // Action specific warning details.
-  repeated ActionWarning actions = 2;
+  uint32 code = 1;
+  oneof warning {
+    FieldWarning request_field = 2 [json_name = "request_fields"];
+    ActionWarning action = 3;
+    BehaviorWarning behavior = 4;
+  }
+}
 
-  // Boundary behavior warning details.
-  repeated BehaviorWarning behaviors = 3;
+// Warning is returned by the JSON API when a warning occurs.
+message WarningResponse {
+  // Request-field-specific warning details.
+  repeated Warning warnings = 1;
 }

internal/proto/controller/api/v1/warning.proto

@@ -0,0 +1,48 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
+package warning
+
+import pb "github.com/hashicorp/boundary/internal/gen/controller/api"
+
+type apiWarning uint32
+
+// The set of warnings that boundary ever returns as a result of API requests.
+// Besides zzzKeepThisLastSentinel, the warnings should keep the numbers they
+// are initially released with because the enumerated number is used to uniquely
+// identify them and potentially provide additional information in documentation.
+const (
+	Unknown                                apiWarning = 0
+	FieldDeprecatedTargetWorkerFilters     apiWarning = 1
+	OidcAuthMethodInactiveCannotBeUsed     apiWarning = 2
+	DeletingKmsLedWorkersMayNotBePermanent apiWarning = 3
+
+	// This is a sentinel value that captures the largest apiWarning id currently
+	// known.  Add all warnings above this line.
+	zzzKeepThisLastSentinel
+)
+
+func (a apiWarning) toProto() *pb.Warning {
+	nw := &pb.Warning{
+		Code: uint32(a),
+	}
+	switch a {
+	case FieldDeprecatedTargetWorkerFilters:
+		nw.Warning = &pb.Warning_RequestField{RequestField: &pb.FieldWarning{
+			Name:    "worker_filter",
+			Warning: "This field is deprecated. Please use ingress_worker_filter and/or egress_worker_filter",
+		}}
+	case OidcAuthMethodInactiveCannotBeUsed:
+		nw.Warning = &pb.Warning_Behavior{Behavior: &pb.BehaviorWarning{
+			Warning: "OIDC Auth Methods cannot be authenticated until they have been made active.",
+		}}
+	case DeletingKmsLedWorkersMayNotBePermanent:
+		nw.Warning = &pb.Warning_Behavior{Behavior: &pb.BehaviorWarning{
+			Warning: "A KMS worker may be automatically recreated after deletion if it is still running.",
+		}}
+	default:
+		// don't add any unknown warning to the warner
+		return nil
+	}
+	return nw
+}