Update with start (#381)

Fixes #346

README.md

@@ -541,6 +541,9 @@ Some things to note about the above code:
 * A shortcut extension `ExecuteWorkflowAsync` is available that is just `StartWorkflowAsync` + `GetResultAsync`.
 * `SignalWithStart` method is present on the workflow options to make the workflow call a signal-with-start call which
   means it will only start the workflow if it's not running, but send a signal to it regardless.
+* Separate `StartUpdateWithStartWorkflowAsync` and `ExecuteUpdateWithStartWorkflowAsync` methods are present on the
+  client to make the workflow call an update-with-start call which means it may start the workflow if it's not running,
+  but perform an update on it regardless.
 
 #### Invoking Activities
 

src/Temporalio.Extensions.OpenTelemetry/TracingInterceptor.cs

@@ -124,6 +124,27 @@ protected virtual IDictionary<string, Payload> HeadersFromContext(
             return Enumerable.Empty<KeyValuePair<string, object?>>();
         }
 
+        /// <summary>
+        /// Create tag collection for the given workflow and update ID.
+        /// </summary>
+        /// <param name="workflowId">Workflow ID.</param>
+        /// <param name="updateId">Update ID.</param>
+        /// <returns>Tags.</returns>
+        protected virtual IEnumerable<KeyValuePair<string, object?>> CreateUpdateTags(
+            string workflowId, string? updateId)
+        {
+            var ret = new List<KeyValuePair<string, object?>>(2);
+            if (Options.TagNameWorkflowId is string wfName)
+            {
+                ret.Add(new(wfName, workflowId));
+            }
+            if (Options.TagNameUpdateId is string updateName && updateId is { } nonNullUpdateId)
+            {
+                ret.Add(new(updateName, nonNullUpdateId));
+            }
+            return ret;
+        }
+
         /// <summary>
         /// Create tag collection from the current workflow environment. Must be called within a
         /// workflow.
@@ -208,6 +229,48 @@ public override async Task<WorkflowHandle<TWorkflow, TResult>> StartWorkflowAsyn
                 }
             }
 
+            public override async Task<WorkflowUpdateHandle<TUpdateResult>> StartUpdateWithStartWorkflowAsync<TUpdateResult>(
+                StartUpdateWithStartWorkflowInput input)
+            {
+                // Ignore if for some reason the start operation is not set by this interceptor
+                if (input.Options.StartWorkflowOperation == null)
+                {
+                    return await base.StartUpdateWithStartWorkflowAsync<TUpdateResult>(input).ConfigureAwait(false);
+                }
+
+                using (var activity = ClientSource.StartActivity(
+                    $"UpdateWithStartWorkflow:{input.Options.StartWorkflowOperation.Workflow}",
+                    kind: ActivityKind.Client,
+                    parentContext: default,
+                    tags: root.CreateUpdateTags(
+                        workflowId: input.Options.StartWorkflowOperation.Options.Id!,
+                        updateId: input.Options.Id)))
+                {
+                    // We want the header on _both_ start and update
+                    if (HeadersFromContext(input.Headers) is Dictionary<string, Payload> updateHeaders)
+                    {
+                        input = input with { Headers = updateHeaders };
+                    }
+                    if (HeadersFromContext(input.Options.StartWorkflowOperation.Headers) is Dictionary<string, Payload> startHeaders)
+                    {
+                        // We copy the operation but still mutate the existing headers. This is
+                        // similar to what is done by other interceptors (they copy the input
+                        // object but still mutate the original header dictionary if there).
+                        input.Options.StartWorkflowOperation = (WithStartWorkflowOperation)input.Options.StartWorkflowOperation.Clone();
+                        input.Options.StartWorkflowOperation.Headers = startHeaders;
+                    }
+                    try
+                    {
+                        return await base.StartUpdateWithStartWorkflowAsync<TUpdateResult>(input).ConfigureAwait(false);
+                    }
+                    catch (Exception e)
+                    {
+                        RecordExceptionWithStatus(activity, e);
+                        throw;
+                    }
+                }
+            }
+
             public override async Task SignalWorkflowAsync(SignalWorkflowInput input)
             {
                 using (var activity = ClientSource.StartActivity(
@@ -263,7 +326,7 @@ public override async Task<WorkflowUpdateHandle<TResult>> StartWorkflowUpdateAsy
                     $"UpdateWorkflow:{input.Update}",
                     kind: ActivityKind.Client,
                     parentContext: default,
-                    tags: root.CreateWorkflowTags(input.Id)))
+                    tags: root.CreateUpdateTags(workflowId: input.Id, updateId: input.Options.Id)))
                 {
                     if (HeadersFromContext(input.Headers) is Dictionary<string, Payload> headers)
                     {

src/Temporalio.Extensions.OpenTelemetry/TracingInterceptorOptions.cs

@@ -33,6 +33,11 @@ public class TracingInterceptorOptions : ICloneable
         /// </summary>
         public string? TagNameActivityId { get; set; } = "temporalActivityID";
 
+        /// <summary>
+        /// Gets or sets the tag name for update IDs. If null, no tag is created.
+        /// </summary>
+        public string? TagNameUpdateId { get; set; } = "temporalUpdateID";
+
         /// <summary>
         /// Create a shallow copy of these options.
         /// </summary>

src/Temporalio/Client/ITemporalClient.Workflow.cs

@@ -92,6 +92,84 @@ WorkflowHandle<TWorkflow> GetWorkflowHandle<TWorkflow>(
         WorkflowHandle<TWorkflow, TResult> GetWorkflowHandle<TWorkflow, TResult>(
             string id, string? runId = null, string? firstExecutionRunId = null);
 
+        /// <summary>
+        /// Start an update via a call to a WorkflowUpdate attributed method, possibly starting the
+        /// workflow at the same time. Note that in some cases this call may fail but the workflow
+        /// will still be started.
+        /// </summary>
+        /// <typeparam name="TWorkflow">Workflow class type.</typeparam>
+        /// <param name="updateCall">Invocation of workflow update method.</param>
+        /// <param name="options">Update options. Currently <c>WaitForStage</c> is required.</param>
+        /// <returns>Workflow update handle.</returns>
+        /// <exception cref="ArgumentException">Invalid run call or options.</exception>
+        /// <exception cref="Exceptions.WorkflowAlreadyStartedException">
+        /// Workflow was already started according to ID reuse and conflict policy.
+        /// </exception>
+        /// <exception cref="Exceptions.RpcException">Server-side error.</exception>
+        /// <remarks>WARNING: Workflow update with start is experimental and APIs may change.
+        /// </remarks>
+        Task<WorkflowUpdateHandle> StartUpdateWithStartWorkflowAsync<TWorkflow>(
+            Expression<Func<TWorkflow, Task>> updateCall,
+            WorkflowStartUpdateWithStartOptions options);
+
+        /// <summary>
+        /// Start an update via a call to a WorkflowUpdate attributed method, possibly starting the
+        /// workflow at the same time. Note that in some cases this call may fail but the workflow
+        /// will still be started.
+        /// </summary>
+        /// <typeparam name="TWorkflow">Workflow class type.</typeparam>
+        /// <typeparam name="TUpdateResult">Update result type.</typeparam>
+        /// <param name="updateCall">Invocation of workflow update method.</param>
+        /// <param name="options">Update options. Currently <c>WaitForStage</c> is required.</param>
+        /// <returns>Workflow update handle.</returns>
+        /// <exception cref="ArgumentException">Invalid run call or options.</exception>
+        /// <exception cref="Exceptions.WorkflowAlreadyStartedException">
+        /// Workflow was already started according to ID reuse and conflict policy.
+        /// </exception>
+        /// <exception cref="Exceptions.RpcException">Server-side error.</exception>
+        /// <remarks>WARNING: Workflow update with start is experimental and APIs may change.
+        /// </remarks>
+        Task<WorkflowUpdateHandle<TUpdateResult>> StartUpdateWithStartWorkflowAsync<TWorkflow, TUpdateResult>(
+            Expression<Func<TWorkflow, Task<TUpdateResult>>> updateCall,
+            WorkflowStartUpdateWithStartOptions options);
+
+        /// <summary>
+        /// Start an update using its name, possibly starting the workflow at the same time. Note
+        /// that in some cases this call may fail but the workflow will still be started.
+        /// </summary>
+        /// <param name="update">Name of the update.</param>
+        /// <param name="args">Arguments for the update.</param>
+        /// <param name="options">Update options. Currently <c>WaitForStage</c> is required.</param>
+        /// <returns>Workflow update handle.</returns>
+        /// <exception cref="ArgumentException">Invalid run call or options.</exception>
+        /// <exception cref="Exceptions.WorkflowAlreadyStartedException">
+        /// Workflow was already started according to ID reuse and conflict policy.
+        /// </exception>
+        /// <exception cref="Exceptions.RpcException">Server-side error.</exception>
+        /// <remarks>WARNING: Workflow update with start is experimental and APIs may change.
+        /// </remarks>
+        Task<WorkflowUpdateHandle> StartUpdateWithStartWorkflowAsync(
+            string update, IReadOnlyCollection<object?> args, WorkflowStartUpdateWithStartOptions options);
+
+        /// <summary>
+        /// Start an update using its name, possibly starting the workflow at the same time. Note
+        /// that in some cases this call may fail but the workflow will still be started.
+        /// </summary>
+        /// <typeparam name="TUpdateResult">Update result type.</typeparam>
+        /// <param name="update">Name of the update.</param>
+        /// <param name="args">Arguments for the update.</param>
+        /// <param name="options">Update options. Currently <c>WaitForStage</c> is required.</param>
+        /// <returns>Workflow update handle.</returns>
+        /// <exception cref="ArgumentException">Invalid run call or options.</exception>
+        /// <exception cref="Exceptions.WorkflowAlreadyStartedException">
+        /// Workflow was already started according to ID reuse and conflict policy.
+        /// </exception>
+        /// <exception cref="Exceptions.RpcException">Server-side error.</exception>
+        /// <remarks>WARNING: Workflow update with start is experimental and APIs may change.
+        /// </remarks>
+        Task<WorkflowUpdateHandle<TUpdateResult>> StartUpdateWithStartWorkflowAsync<TUpdateResult>(
+            string update, IReadOnlyCollection<object?> args, WorkflowStartUpdateWithStartOptions options);
+
 #if NETCOREAPP3_0_OR_GREATER
         /// <summary>
         /// List workflows with the given query.