.NET: [Feature Branch] Add basic durable workflow support (#3648)

* Add basic durable workflow support. * PR feedback fixes * Add conditional edge sample. * PR feedback fixes. * Minor cleanup. * Minor cleanup * Minor formatting improvements. * Improve comments/documentation on the execution flow.
2026-06-16 21:04:09 +08:00 · 2026-02-06 16:02:42 -08:00
parent 98cd72839e
commit e8d0bd9051
54 changed files with 4863 additions and 505 deletions
@@ -0,0 +1,107 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System.Diagnostics;
+using System.Diagnostics.CodeAnalysis;
+using System.Text.Json;
+using Microsoft.Agents.AI.Workflows;
+
+namespace Microsoft.Agents.AI.DurableTask.Workflows;
+
+/// <summary>
+/// A workflow context for durable activity execution.
+/// </summary>
+/// <remarks>
+/// Some of the methods are returning default for this version. Those method will be updated with real implementations in follow up PRs.
+/// </remarks>
+[DebuggerDisplay("Executor = {_executor.Id}, StateEntries = {_initialState.Count}")]
+internal sealed class DurableActivityContext : IWorkflowContext
+{
+    private readonly Dictionary<string, string> _initialState;
+    private readonly Executor _executor;
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="DurableActivityContext"/> class.
+    /// </summary>
+    /// <param name="initialState">The shared state passed from the orchestration.</param>
+    /// <param name="executor">The executor running in this context.</param>
+    internal DurableActivityContext(Dictionary<string, string>? initialState, Executor executor)
+    {
+        this._executor = executor;
+        this._initialState = initialState ?? [];
+    }
+
+    /// <summary>
+    /// Gets the messages sent during activity execution via <see cref="SendMessageAsync"/>.
+    /// </summary>
+    internal List<SentMessageInfo> SentMessages { get; } = [];
+
+    /// <inheritdoc/>
+    public ValueTask AddEventAsync(
+        WorkflowEvent workflowEvent,
+        CancellationToken cancellationToken = default) => default;
+
+    /// <inheritdoc/>
+    [UnconditionalSuppressMessage("AOT", "IL3050", Justification = "Serializing workflow message types registered at startup.")]
+    [UnconditionalSuppressMessage("Trimming", "IL2026", Justification = "Serializing workflow message types registered at startup.")]
+    public ValueTask SendMessageAsync(
+        object message,
+        string? targetId = null,
+        CancellationToken cancellationToken = default)
+    {
+        if (message is not null)
+        {
+            Type messageType = message.GetType();
+            this.SentMessages.Add(new SentMessageInfo
+            {
+                Message = JsonSerializer.Serialize(message, messageType),
+                TypeName = messageType.FullName ?? messageType.Name
+            });
+        }
+
+        return default;
+    }
+
+    /// <inheritdoc/>
+    public ValueTask YieldOutputAsync(
+        object output,
+        CancellationToken cancellationToken = default) => default;
+
+    /// <inheritdoc/>
+    public ValueTask RequestHaltAsync() => default;
+
+    /// <inheritdoc/>
+    public ValueTask<T?> ReadStateAsync<T>(
+        string key,
+        string? scopeName = null,
+        CancellationToken cancellationToken = default) => default;
+
+    /// <inheritdoc/>
+    public ValueTask<T> ReadOrInitStateAsync<T>(
+        string key,
+        Func<T> initialStateFactory,
+        string? scopeName = null,
+        CancellationToken cancellationToken = default) => default;
+
+    /// <inheritdoc/>
+    public ValueTask<HashSet<string>> ReadStateKeysAsync(
+        string? scopeName = null,
+        CancellationToken cancellationToken = default) => default;
+
+    /// <inheritdoc/>
+    public ValueTask QueueStateUpdateAsync<T>(
+        string key,
+        T? value,
+        string? scopeName = null,
+        CancellationToken cancellationToken = default) => default;
+
+    /// <inheritdoc/>
+    public ValueTask QueueClearScopeAsync(
+        string? scopeName = null,
+        CancellationToken cancellationToken = default) => default;
+
+    /// <inheritdoc/>
+    public IReadOnlyDictionary<string, string>? TraceContext => null;
+
+    /// <inheritdoc/>
+    public bool ConcurrentRunsEnabled => false;
+}