Adding fields necessary for implementing extended sessions in DTS

protos/backend_service.proto

@@ -71,15 +71,31 @@ service BackendService {
     // Completes an outstanding orchestrator work item, and adds a new event to the target orchestration's inbox.
     rpc CompleteOrchestrationWorkItem (CompleteOrchestrationWorkItemRequest) returns (CompleteOrchestrationWorkItemResponse);
 
+    // Completes an outstanding orchestrator work item, and adds a new event to the target orchestration's inbox.
+    // Immediately returns a CompleteOrchestrationWorkItemResponse upon committal of the work item, and in the case
+    // of an extended session, will continue to stream any new messages to the orchestration until the call is cancelled.
+    rpc CompleteOrchestrationWorkItemWithExtendedSession (CompleteOrchestrationWorkItemRequest) returns (stream CompleteInstanceWorkItemResponse);
+
     // Abandons an outstanding orchestrator work item. Abandoned work items will be delivered again after some delay.
     rpc AbandonOrchestrationWorkItem (AbandonOrchestrationWorkItemRequest) returns (AbandonOrchestrationWorkItemResponse);
 
+    // Releases an orchestration work item.
+    rpc ReleaseOrchestrationWorkItem(ReleaseOrchestrationWorkItemRequest) returns (ReleaseOrchestrationWorkItemResponse);
+
     // Completes an outstanding entity work item.
     rpc CompleteEntityWorkItem (CompleteEntityWorkItemRequest) returns (CompleteEntityWorkItemResponse);
 
+    // Completes an outstanding entity work item.
+    // Immediately returns a CompleteEntityWorkItemResponse upon committal of the work item, and in the case
+    // of an extended session, will continue to stream any new messages to the entity until the call is cancelled.
+    rpc CompleteEntityWorkItemWithExtendedSession (CompleteEntityWorkItemRequest) returns (stream CompleteInstanceWorkItemResponse);
+
     // Abandons an outstanding entity work item. Abandoned work items will be delivered again after some delay.
     rpc AbandonEntityWorkItem (AbandonEntityWorkItemRequest) returns (AbandonEntityWorkItemResponse);
 
+    // Releases an entity work item.
+    rpc ReleaseEntityWorkItem(ReleaseEntityWorkItemRequest) returns (ReleaseEntityWorkItemResponse);
+
     // Sends a health check ping to the backend service.
     rpc Ping (PingRequest) returns (PingResponse);
 
@@ -191,11 +207,18 @@ message CompleteOrchestrationWorkItemRequest {
     // Zero-based position of the current chunk within a chunked completion sequence.
     // This field is omitted for non-chunked completions.
     google.protobuf.Int32Value chunkIndex = 12;
+
+    bool isExtendedSession = 13;
+
+    // Only non-zero in the case of chunked completions or when extended sessions are active, in which case complete
+    // will be called multiple times for the same instance work item. This field is incremented for each completion
+    // call so the backend can identify redundant completion calls for the same chunk or set of instance messages.
+    int32 completionCount = 14;
 }
 
 // Response payload for completing an orchestration work item.
 message CompleteOrchestrationWorkItemResponse {
-	// No fields
+    // No fields
 }
 
 // A message to be delivered to an orchestration by the backend.
@@ -236,6 +259,16 @@ message CompleteEntityWorkItemRequest {
     // The messages that were sent by the executed operations. This must
     // include any responses to the operation calls.
     repeated OrchestratorMessage messages = 5;
+
+    bool isExtendedSession = 6;
+
+    string instanceId = 7;
+
+    // Only non-zero in the case when an extended sessions is active, in which case complete
+    // will be called multiple times for the same instance work item. This field is incremented
+    // for each completion call so the backend can identify redundant completion calls for the same
+    // set of instance messages.
+    int32 completionCount = 8;
 }
 
 // Response payload for completing an entity work item.
@@ -303,3 +336,33 @@ message ConnectedWorkerMetrics {
     // Number of worker instances that are currently connected to the backend
     int32 count = 1 [json_name="count"];
 }
+
+// Request payload for releasing an orchestration work item.
+message ReleaseOrchestrationWorkItemRequest {
+    // The completion token that was provided when the work item was fetched.
+    string completionToken = 1;
+}
+
+// Response payload for releasing an orchestration work item.
+message ReleaseOrchestrationWorkItemResponse {
+	// No fields
+}
+
+// Request payload for releasing an entity work item.
+message ReleaseEntityWorkItemRequest {
+    // The completion token that was provided when the work item was fetched.
+    string completionToken = 1;
+}
+
+// Response payload for releasing an entity work item.
+message ReleaseEntityWorkItemResponse {
+	// No fields
+}
+
+message CompleteInstanceWorkItemResponse {
+    oneof request {
+        CompleteOrchestrationWorkItemResponse orchestratorResponse = 1;
+        CompleteEntityWorkItemResponse entityResponse = 2;
+        HistoryChunk newMessages = 3;
+    }
+}