feat: allow a result record to hold a resource in an own<T> field

GUIDE.md

@@ -713,6 +713,27 @@ return StartedWorkflow(
 If a resource constructor field name cannot be found in either, the generator
 raises `InvalidResource`.
 
+**A result record that holds the resource.** An operation can also return a
+proto-backed record with one `own<T>` field and other fields. The resource binds
+from the record's message as above, and the other fields come from the fields of
+the same name. The record is the API model only, and it declares only the fields
+that its caller sees. Its message travels as a wire record that takes the proto
+message's name. Python, TypeScript, .NET and Go generate it. In Python, the
+record lives in its resource's module.
+
+```wit
+/// @nexus.proto "acme.jobs.v1.CreateJobResponse"
+record create-job-result {
+  job: own<job>,
+  created: option<bool>,
+}
+```
+
+```python
+result = await handle  # CreateJobResponse
+return CreateJobResult(job=Job(job_id=result.job_id), created=result.created)
+```
+
 ### Edge Cases and Error Conditions
 
 #### Same field name in constructor and method parameter

advanced/samples/README.md

@@ -206,4 +206,5 @@ protoc -I descriptors -I "$API" --csharp_out=dotnet/proto streamsample/v1/stream
 ```
 
 The TypeScript `typescript/proto/streamsample.d.ts` mirrors the proto by hand,
-with only the `I<Message>` interfaces that the generated code imports.
+with only the `I<Message>` interfaces and the enums that the generated code
+imports.

advanced/samples/descriptors/streamsample/v1/stream_service.proto

@@ -30,9 +30,17 @@ message CreateStreamRequest {
     google.protobuf.Duration retention = 3;
 }
 
+enum StreamStatus {
+    STREAM_STATUS_UNSPECIFIED = 0;
+    STREAM_STATUS_OPEN = 1;
+    STREAM_STATUS_CLOSED = 2;
+    STREAM_STATUS_EXPIRED = 3;
+}
+
 message CreateStreamResponse {
     StreamRef stream = 1;
     bool created = 2;
+    StreamStatus status = 3;
 }
 
 message AppendRecordsRequest {

advanced/samples/dotnet/proto/StreamService.cs

@@ -34,36 +34,40 @@ static StreamServiceReflection() {
             "bXBvcmFsLmFwaS5jb21tb24udjEuUGF5bG9hZCJ/ChNDcmVhdGVTdHJlYW1S",
             "ZXF1ZXN0EhEKCW5hbWVzcGFjZRgBIAEoCRInCgNyZWYYAiABKAsyGi5zdHJl",
             "YW1zYW1wbGUudjEuU3RyZWFtUmVmEiwKCXJldGVudGlvbhgDIAEoCzIZLmdv",
-            "b2dsZS5wcm90b2J1Zi5EdXJhdGlvbiJTChRDcmVhdGVTdHJlYW1SZXNwb25z",
-            "ZRIqCgZzdHJlYW0YASABKAsyGi5zdHJlYW1zYW1wbGUudjEuU3RyZWFtUmVm",
-            "Eg8KB2NyZWF0ZWQYAiABKAgilwEKFEFwcGVuZFJlY29yZHNSZXF1ZXN0EhEK",
-            "CW5hbWVzcGFjZRgBIAEoCRIqCgZzdHJlYW0YAiABKAsyGi5zdHJlYW1zYW1w",
-            "bGUudjEuU3RyZWFtUmVmEhAKCHNlcXVlbmNlGAMgASgDEi4KB3JlY29yZHMY",
-            "BCADKAsyHS5zdHJlYW1zYW1wbGUudjEuQXBwZW5kUmVjb3JkIkIKFUFwcGVu",
-            "ZFJlY29yZHNSZXNwb25zZRIUCgxmaXJzdF9vZmZzZXQYASABKAMSEwoLbGFz",
-            "dF9vZmZzZXQYAiABKAMihAEKEkNsb3NlU3RyZWFtUmVxdWVzdBIRCgluYW1l",
-            "c3BhY2UYASABKAkSKgoGc3RyZWFtGAIgASgLMhouc3RyZWFtc2FtcGxlLnYx",
-            "LlN0cmVhbVJlZhIvCgZyZXN1bHQYAyABKAsyHy50ZW1wb3JhbC5hcGkuY29t",
-            "bW9uLnYxLlBheWxvYWQiFQoTQ2xvc2VTdHJlYW1SZXNwb25zZSK2AQoSUmVh",
-            "ZFJlY29yZHNSZXF1ZXN0EhEKCW5hbWVzcGFjZRgBIAEoCRIqCgZzdHJlYW0Y",
-            "AiABKAsyGi5zdHJlYW1zYW1wbGUudjEuU3RyZWFtUmVmEhMKC2Zyb21fb2Zm",
-            "c2V0GAMgASgDEg4KBnRvcGljcxgEIAMoCRITCgttYXhfcmVjb3JkcxgFIAEo",
-            "BRInCgR3YWl0GAYgASgLMhkuZ29vZ2xlLnByb3RvYnVmLkR1cmF0aW9uImgK",
-            "E1JlYWRSZWNvcmRzUmVzcG9uc2USLgoHcmVjb3JkcxgBIAMoCzIdLnN0cmVh",
-            "bXNhbXBsZS52MS5TdHJlYW1SZWNvcmQSEwoLbmV4dF9vZmZzZXQYAiABKAMS",
-            "DAoEZG9uZRgDIAEoCCJWChVEZXNjcmliZVN0cmVhbVJlcXVlc3QSEQoJbmFt",
-            "ZXNwYWNlGAEgASgJEioKBnN0cmVhbRgCIAEoCzIaLnN0cmVhbXNhbXBsZS52",
-            "MS5TdHJlYW1SZWYiWwoWRGVzY3JpYmVTdHJlYW1SZXNwb25zZRITCgtsYXN0",
-            "X29mZnNldBgBIAEoAxIsCglyZXRlbnRpb24YAiABKAsyGS5nb29nbGUucHJv",
-            "dG9idWYuRHVyYXRpb25CEqoCD1N0cmVhbVNhbXBsZS5WMWIGcHJvdG8z"));
+            "b2dsZS5wcm90b2J1Zi5EdXJhdGlvbiKCAQoUQ3JlYXRlU3RyZWFtUmVzcG9u",
+            "c2USKgoGc3RyZWFtGAEgASgLMhouc3RyZWFtc2FtcGxlLnYxLlN0cmVhbVJl",
+            "ZhIPCgdjcmVhdGVkGAIgASgIEi0KBnN0YXR1cxgDIAEoDjIdLnN0cmVhbXNh",
+            "bXBsZS52MS5TdHJlYW1TdGF0dXMilwEKFEFwcGVuZFJlY29yZHNSZXF1ZXN0",
+            "EhEKCW5hbWVzcGFjZRgBIAEoCRIqCgZzdHJlYW0YAiABKAsyGi5zdHJlYW1z",
+            "YW1wbGUudjEuU3RyZWFtUmVmEhAKCHNlcXVlbmNlGAMgASgDEi4KB3JlY29y",
+            "ZHMYBCADKAsyHS5zdHJlYW1zYW1wbGUudjEuQXBwZW5kUmVjb3JkIkIKFUFw",
+            "cGVuZFJlY29yZHNSZXNwb25zZRIUCgxmaXJzdF9vZmZzZXQYASABKAMSEwoL",
+            "bGFzdF9vZmZzZXQYAiABKAMihAEKEkNsb3NlU3RyZWFtUmVxdWVzdBIRCglu",
+            "YW1lc3BhY2UYASABKAkSKgoGc3RyZWFtGAIgASgLMhouc3RyZWFtc2FtcGxl",
+            "LnYxLlN0cmVhbVJlZhIvCgZyZXN1bHQYAyABKAsyHy50ZW1wb3JhbC5hcGku",
+            "Y29tbW9uLnYxLlBheWxvYWQiFQoTQ2xvc2VTdHJlYW1SZXNwb25zZSK2AQoS",
+            "UmVhZFJlY29yZHNSZXF1ZXN0EhEKCW5hbWVzcGFjZRgBIAEoCRIqCgZzdHJl",
+            "YW0YAiABKAsyGi5zdHJlYW1zYW1wbGUudjEuU3RyZWFtUmVmEhMKC2Zyb21f",
+            "b2Zmc2V0GAMgASgDEg4KBnRvcGljcxgEIAMoCRITCgttYXhfcmVjb3JkcxgF",
+            "IAEoBRInCgR3YWl0GAYgASgLMhkuZ29vZ2xlLnByb3RvYnVmLkR1cmF0aW9u",
+            "ImgKE1JlYWRSZWNvcmRzUmVzcG9uc2USLgoHcmVjb3JkcxgBIAMoCzIdLnN0",
+            "cmVhbXNhbXBsZS52MS5TdHJlYW1SZWNvcmQSEwoLbmV4dF9vZmZzZXQYAiAB",
+            "KAMSDAoEZG9uZRgDIAEoCCJWChVEZXNjcmliZVN0cmVhbVJlcXVlc3QSEQoJ",
+            "bmFtZXNwYWNlGAEgASgJEioKBnN0cmVhbRgCIAEoCzIaLnN0cmVhbXNhbXBs",
+            "ZS52MS5TdHJlYW1SZWYiWwoWRGVzY3JpYmVTdHJlYW1SZXNwb25zZRITCgts",
+            "YXN0X29mZnNldBgBIAEoAxIsCglyZXRlbnRpb24YAiABKAsyGS5nb29nbGUu",
+            "cHJvdG9idWYuRHVyYXRpb24qegoMU3RyZWFtU3RhdHVzEh0KGVNUUkVBTV9T",
+            "VEFUVVNfVU5TUEVDSUZJRUQQABIWChJTVFJFQU1fU1RBVFVTX09QRU4QARIY",
+            "ChRTVFJFQU1fU1RBVFVTX0NMT1NFRBACEhkKFVNUUkVBTV9TVEFUVVNfRVhQ",
+            "SVJFRBADQhKqAg9TdHJlYW1TYW1wbGUuVjFiBnByb3RvMw=="));
       descriptor = pbr::FileDescriptor.FromGeneratedCode(descriptorData,
           new pbr::FileDescriptor[] { global::Google.Protobuf.WellKnownTypes.DurationReflection.Descriptor, global::Temporalio.Api.Common.V1.MessageReflection.Descriptor, },
-          new pbr::GeneratedClrTypeInfo(null, null, new pbr::GeneratedClrTypeInfo[] {
+          new pbr::GeneratedClrTypeInfo(new[] {typeof(global::StreamSample.V1.StreamStatus), }, null, new pbr::GeneratedClrTypeInfo[] {
             new pbr::GeneratedClrTypeInfo(typeof(global::StreamSample.V1.StreamRef), global::StreamSample.V1.StreamRef.Parser, new[]{ "Id", "WorkflowId" }, null, null, null, null),
             new pbr::GeneratedClrTypeInfo(typeof(global::StreamSample.V1.AppendRecord), global::StreamSample.V1.AppendRecord.Parser, new[]{ "Topic", "Body" }, null, null, null, null),
             new pbr::GeneratedClrTypeInfo(typeof(global::StreamSample.V1.StreamRecord), global::StreamSample.V1.StreamRecord.Parser, new[]{ "Offset", "Topic", "Body" }, null, null, null, null),
             new pbr::GeneratedClrTypeInfo(typeof(global::StreamSample.V1.CreateStreamRequest), global::StreamSample.V1.CreateStreamRequest.Parser, new[]{ "Namespace", "Ref", "Retention" }, null, null, null, null),
-            new pbr::GeneratedClrTypeInfo(typeof(global::StreamSample.V1.CreateStreamResponse), global::StreamSample.V1.CreateStreamResponse.Parser, new[]{ "Stream", "Created" }, null, null, null, null),
+            new pbr::GeneratedClrTypeInfo(typeof(global::StreamSample.V1.CreateStreamResponse), global::StreamSample.V1.CreateStreamResponse.Parser, new[]{ "Stream", "Created", "Status" }, null, null, null, null),
             new pbr::GeneratedClrTypeInfo(typeof(global::StreamSample.V1.AppendRecordsRequest), global::StreamSample.V1.AppendRecordsRequest.Parser, new[]{ "Namespace", "Stream", "Sequence", "Records" }, null, null, null, null),
             new pbr::GeneratedClrTypeInfo(typeof(global::StreamSample.V1.AppendRecordsResponse), global::StreamSample.V1.AppendRecordsResponse.Parser, new[]{ "FirstOffset", "LastOffset" }, null, null, null, null),
             new pbr::GeneratedClrTypeInfo(typeof(global::StreamSample.V1.CloseStreamRequest), global::StreamSample.V1.CloseStreamRequest.Parser, new[]{ "Namespace", "Stream", "Result" }, null, null, null, null),
@@ -77,6 +81,16 @@ static StreamServiceReflection() {
     #endregion
 
   }
+  #region Enums
+  public enum StreamStatus {
+    [pbr::OriginalName("STREAM_STATUS_UNSPECIFIED")] Unspecified = 0,
+    [pbr::OriginalName("STREAM_STATUS_OPEN")] Open = 1,
+    [pbr::OriginalName("STREAM_STATUS_CLOSED")] Closed = 2,
+    [pbr::OriginalName("STREAM_STATUS_EXPIRED")] Expired = 3,
+  }
+
+  #endregion
+
   #region Messages
   [global::System.Diagnostics.DebuggerDisplayAttribute("{ToString(),nq}")]
   public sealed partial class StreamRef : pb::IMessage<StreamRef>
@@ -1165,6 +1179,7 @@ public CreateStreamResponse() {
     public CreateStreamResponse(CreateStreamResponse other) : this() {
       stream_ = other.stream_ != null ? other.stream_.Clone() : null;
       created_ = other.created_;
+      status_ = other.status_;
       _unknownFields = pb::UnknownFieldSet.Clone(other._unknownFields);
     }
 
@@ -1198,6 +1213,18 @@ public bool Created {
       }
     }
 
+    /// <summary>Field number for the "status" field.</summary>
+    public const int StatusFieldNumber = 3;
+    private global::StreamSample.V1.StreamStatus status_ = global::StreamSample.V1.StreamStatus.Unspecified;
+    [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
+    [global::System.CodeDom.Compiler.GeneratedCode("protoc", null)]
+    public global::StreamSample.V1.StreamStatus Status {
+      get { return status_; }
+      set {
+        status_ = value;
+      }
+    }
+
     [global::System.Diagnostics.DebuggerNonUserCodeAttribute]
     [global::System.CodeDom.Compiler.GeneratedCode("protoc", null)]
     public override bool Equals(object other) {
@@ -1215,6 +1242,7 @@ public bool Equals(CreateStreamResponse other) {
       }
       if (!object.Equals(Stream, other.Stream)) return false;
       if (Created != other.Created) return false;
+      if (Status != other.Status) return false;
       return Equals(_unknownFields, other._unknownFields);
     }
 
@@ -1224,6 +1252,7 @@ public override int GetHashCode() {
       int hash = 1;
       if (stream_ != null) hash ^= Stream.GetHashCode();
       if (Created != false) hash ^= Created.GetHashCode();
+      if (Status != global::StreamSample.V1.StreamStatus.Unspecified) hash ^= Status.GetHashCode();
       if (_unknownFields != null) {
         hash ^= _unknownFields.GetHashCode();
       }
@@ -1250,6 +1279,10 @@ public void WriteTo(pb::CodedOutputStream output) {
         output.WriteRawTag(16);
         output.WriteBool(Created);
       }
+      if (Status != global::StreamSample.V1.StreamStatus.Unspecified) {
+        output.WriteRawTag(24);
+        output.WriteEnum((int) Status);
+      }
       if (_unknownFields != null) {
         _unknownFields.WriteTo(output);
       }
@@ -1268,6 +1301,10 @@ public void WriteTo(pb::CodedOutputStream output) {
         output.WriteRawTag(16);
         output.WriteBool(Created);
       }
+      if (Status != global::StreamSample.V1.StreamStatus.Unspecified) {
+        output.WriteRawTag(24);
+        output.WriteEnum((int) Status);
+      }
       if (_unknownFields != null) {
         _unknownFields.WriteTo(ref output);
       }
@@ -1284,6 +1321,9 @@ public int CalculateSize() {
       if (Created != false) {
         size += 1 + 1;
       }
+      if (Status != global::StreamSample.V1.StreamStatus.Unspecified) {
+        size += 1 + pb::CodedOutputStream.ComputeEnumSize((int) Status);
+      }
       if (_unknownFields != null) {
         size += _unknownFields.CalculateSize();
       }
@@ -1305,6 +1345,9 @@ public void MergeFrom(CreateStreamResponse other) {
       if (other.Created != false) {
         Created = other.Created;
       }
+      if (other.Status != global::StreamSample.V1.StreamStatus.Unspecified) {
+        Status = other.Status;
+      }
       _unknownFields = pb::UnknownFieldSet.MergeFrom(_unknownFields, other._unknownFields);
     }
 
@@ -1335,6 +1378,10 @@ public void MergeFrom(pb::CodedInputStream input) {
             Created = input.ReadBool();
             break;
           }
+          case 24: {
+            Status = (global::StreamSample.V1.StreamStatus) input.ReadEnum();
+            break;
+          }
         }
       }
     #endif
@@ -1365,6 +1412,10 @@ public void MergeFrom(pb::CodedInputStream input) {
             Created = input.ReadBool();
             break;
           }
+          case 24: {
+            Status = (global::StreamSample.V1.StreamStatus) input.ReadEnum();
+            break;
+          }
         }
       }
     }

advanced/samples/dotnet/wit/stream-service/Models.cs

@@ -10,6 +10,68 @@
 namespace Nexgen.StreamService
 {
 
+    [GeneratedCode("nexgen", null)]
+    public enum StreamStatus
+    {
+        StreamStatusUnspecified = 0,
+        StreamStatusOpen = 1,
+        StreamStatusClosed = 2,
+        StreamStatusExpired = 3,
+    }
+
+    [Temporalio.Converters.TemporalTransferTypeConverter(typeof(CreateStreamResponse.TransferTypeConverter))]
+    [GeneratedCode("nexgen", null)]
+    public record CreateStreamResponse
+    {
+        public StreamRef? Stream { get; init; }
+        public bool? Created { get; init; }
+        public StreamStatus? Status { get; init; }
+
+        internal static CreateStreamResponse FromTransferType(StreamSample.V1.CreateStreamResponse wire)
+        {
+            return new CreateStreamResponse()
+            {
+                Stream = wire.Stream == null ? null : StreamRef.FromTransferType(wire.Stream),
+                Created = wire.Created == false ? null : wire.Created,
+                Status = (int)wire.Status == 0 ? null : (StreamStatus)wire.Status,
+            };
+        }
+
+        internal StreamSample.V1.CreateStreamResponse ToTransferType()
+        {
+            var proto = new StreamSample.V1.CreateStreamResponse();
+            if (Stream is { } stream)
+            {
+                proto.Stream = (StreamSample.V1.StreamRef)stream.ToTransferType();
+            }
+            if (Created is { } created)
+            {
+                proto.Created = created;
+            }
+            if (Status is { } status)
+            {
+                proto.Status = (StreamSample.V1.StreamStatus)status;
+            }
+            return proto;
+        }
+
+        /// <summary>
+        /// Converts this model to and from its generated transfer type.
+        /// </summary>
+        public sealed class TransferTypeConverter : Temporalio.Converters.ITemporalTransferTypeConverter
+        {
+            /// <summary>Gets the generated transfer type.</summary>
+            public System.Type TransferType => typeof(StreamSample.V1.CreateStreamResponse);
+
+            /// <summary>Converts a model value to its transfer type.</summary>
+            public object? ToTransferType(object? value) => value is null ? null : ((CreateStreamResponse)value).ToTransferType();
+
+            /// <summary>Converts a transfer-type value to this model.</summary>
+            public object? FromTransferType(object? transferType) => transferType is null ? null : CreateStreamResponse.FromTransferType((StreamSample.V1.CreateStreamResponse)transferType);
+        }
+
+    }
+
     [Temporalio.Converters.TemporalTransferTypeConverter(typeof(AppendRecord.TransferTypeConverter))]
     [GeneratedCode("nexgen", null)]
     public record AppendRecord
@@ -286,45 +348,20 @@ public sealed class TransferTypeConverter : Temporalio.Converters.ITemporalTrans
 
     }
 
-    [Temporalio.Converters.TemporalTransferTypeConverter(typeof(CreateStreamResult.TransferTypeConverter))]
     [GeneratedCode("nexgen", null)]
     public record CreateStreamResult
     {
-        public StreamRef? Stream { get; init; }
-
-        internal static CreateStreamResult FromTransferType(StreamSample.V1.CreateStreamResponse wire)
-        {
-            return new CreateStreamResult()
-            {
-                Stream = wire.Stream == null ? null : StreamRef.FromTransferType(wire.Stream),
-            };
-        }
-
-        internal StreamSample.V1.CreateStreamResponse ToTransferType()
-        {
-            var proto = new StreamSample.V1.CreateStreamResponse();
-            if (Stream is { } stream)
-            {
-                proto.Stream = (StreamSample.V1.StreamRef)stream.ToTransferType();
-            }
-            return proto;
-        }
-
         /// <summary>
-        /// Converts this model to and from its generated transfer type.
+        /// Initializes a new instance of the <see cref="CreateStreamResult"/> class.
         /// </summary>
-        public sealed class TransferTypeConverter : Temporalio.Converters.ITemporalTransferTypeConverter
+        public CreateStreamResult(Stream stream)
         {
-            /// <summary>Gets the generated transfer type.</summary>
-            public System.Type TransferType => typeof(StreamSample.V1.CreateStreamResponse);
-
-            /// <summary>Converts a model value to its transfer type.</summary>
-            public object? ToTransferType(object? value) => value is null ? null : ((CreateStreamResult)value).ToTransferType();
-
-            /// <summary>Converts a transfer-type value to this model.</summary>
-            public object? FromTransferType(object? transferType) => transferType is null ? null : CreateStreamResult.FromTransferType((StreamSample.V1.CreateStreamResponse)transferType);
+            Stream = stream;
         }
 
+        public Stream Stream { get; init; }
+        public bool? Created { get; init; }
+        public StreamStatus? Status { get; init; }
     }
 
     [Temporalio.Converters.TemporalTransferTypeConverter(typeof(DescribeStreamRequest.TransferTypeConverter))]

advanced/samples/dotnet/wit/stream-service/Operations.cs

@@ -79,16 +79,16 @@ public static class Operations
         private const string StreamServiceEndpoint = "streams";
 
         [GeneratedCode("nexgen", null)]
-        private static async Task<Stream> CreateStreamAsync(CreateStreamRequest request)
+        private static async Task<CreateStreamResult> CreateStreamAsync(CreateStreamRequest request)
         {
             var client = Workflow.CreateNexusWorkflowClient<IStreamService>(StreamServiceEndpoint);
-            var result = await client.ExecuteNexusOperationAsync<CreateStreamResult>(svc => svc.CreateStream(request)).ConfigureAwait(true);
-            return new Stream((result.Stream ?? throw new System.InvalidOperationException("CreateStream answered without `stream`")));
+            var result = await client.ExecuteNexusOperationAsync<CreateStreamResponse>(svc => svc.CreateStream(request)).ConfigureAwait(true);
+            return new CreateStreamResult(new Stream((result.Stream ?? throw new System.InvalidOperationException("CreateStream answered without `stream`")))) { Created = result.Created, Status = result.Status };
         }
 
         /// <param name="options">Options for the operation.</param>
         [GeneratedCode("nexgen", null)]
-        public static Task<Stream> CreateStreamAsync(CreateStreamOptions? options = null)
+        public static Task<CreateStreamResult> CreateStreamAsync(CreateStreamOptions? options = null)
         {
             var request = new CreateStreamRequest()
             {