ci: stub to satisfy doc generators

Author: JerrettDavis

src/PatternKit.Examples/Generators/OrchestratorStepFactory.Stub.cs

@@ -0,0 +1,49 @@
+using System;
+using System.Collections.Generic;
+using PatternKit.Generators.Factories;
+
+namespace PatternKit.Examples.Generators;
+
+// NOTE: This is a minimal stub to ensure the examples and docfx metadata build without
+// depending on source generator output. The real implementation may be augmented
+// by the PatternKit.Generators FactoryClass source generator via partial types.
+
+public partial class OrchestratorStepFactory
+{
+    private readonly IServiceProvider _services;
+    private readonly IReadOnlyDictionary<string, Type> _stepTypes;
+
+    public OrchestratorStepFactory(IServiceProvider? services = null)
+    {
+        _services = services ?? throw new ArgumentNullException(nameof(services));
+
+        // These keys must match the [FactoryClassKey] attributes on the step types.
+        _stepTypes = new Dictionary<string, Type>(StringComparer.OrdinalIgnoreCase)
+        {
+            { "seed", typeof(SeedDataStep) },
+            { "warm-cache", typeof(WarmCacheStep) },
+            { "start-workers", typeof(StartWorkersStep) },
+        };
+    }
+
+    // Use a different method name so we don't collide with the source-generated
+    // OrchestratorStepFactory.Create method.
+    public IOrchestratorStep CreateFromKey(string key)
+    {
+        if (key is null) throw new ArgumentNullException(nameof(key));
+
+        if (!_stepTypes.TryGetValue(key, out var type))
+        {
+            throw new KeyNotFoundException($"Unknown orchestrator step key: '{key}'.");
+        }
+
+        // Resolve from the service provider if possible, otherwise fall back to Activator.
+        var instance = _services.GetService(type) ?? Activator.CreateInstance(type);
+        if (instance is not IOrchestratorStep step)
+        {
+            throw new InvalidOperationException($"Type '{type.FullName}' does not implement {nameof(IOrchestratorStep)}.");
+        }
+
+        return step;
+    }
+}