feat(governance-runtime): propagate request metadata into governed mutations

Author: rian-be

src/Governance/Runtime/Execution/Mutation/GovernedMutation.cs

@@ -2,19 +2,26 @@
 using ModularityKit.Mutator.Abstractions.Engine;
 using ModularityKit.Mutator.Abstractions.Intent;
 using ModularityKit.Mutator.Abstractions.Results;
+using ModularityKit.Mutator.Governance.Abstractions.Requests.Model;
 
 namespace ModularityKit.Mutator.Governance.Runtime.Execution.Mutation;
 
 /// <summary>
-/// Wraps a mutation so governance request identifiers flow into core execution audit and history metadata.
+/// Wraps mutation so governance request identifiers flow into core execution audit and history metadata.
 /// </summary>
 internal sealed class GovernedMutation<TState> : IMutation<TState>
 {
+    private const string GovernanceRequestIdMetadataKey = "GovernanceRequestId";
+    private const string GovernanceRequestMetadataKey = "GovernanceRequestMetadata";
+    private const string GovernanceIntentMetadataKey = "GovernanceIntentMetadata";
+    private const string GovernanceEstimatedBlastRadiusMetadataKey = "GovernanceEstimatedBlastRadius";
+
     private readonly IMutation<TState> _inner;
 
-    public GovernedMutation(IMutation<TState> inner, string requestId, string stateId)
+    public GovernedMutation(IMutation<TState> inner, MutationRequest request)
     {
         _inner = inner ?? throw new ArgumentNullException(nameof(inner));
+        ArgumentNullException.ThrowIfNull(request);
 
         Intent = new MutationIntent
         {
@@ -23,17 +30,17 @@ public GovernedMutation(IMutation<TState> inner, string requestId, string stateI
             Description = _inner.Intent.Description,
             RiskLevel = _inner.Intent.RiskLevel,
             IsReversible = _inner.Intent.IsReversible,
-            EstimatedBlastRadius = _inner.Intent.EstimatedBlastRadius,
-            Tags = _inner.Intent.Tags,
+            EstimatedBlastRadius = request.Intent.EstimatedBlastRadius ?? _inner.Intent.EstimatedBlastRadius,
+            Tags = MergeTags(request.Intent.Tags, _inner.Intent.Tags),
             CreatedAt = _inner.Intent.CreatedAt,
-            Metadata = MergeMetadata(_inner.Intent.Metadata, requestId)
+            Metadata = MergeIntentMetadata(request)
         };
 
         Context = _inner.Context with
         {
-            StateId = string.IsNullOrWhiteSpace(_inner.Context.StateId) ? stateId : _inner.Context.StateId,
-            CorrelationId = string.IsNullOrWhiteSpace(_inner.Context.CorrelationId) ? requestId : _inner.Context.CorrelationId,
-            Metadata = MergeMetadata(_inner.Context.Metadata, requestId)
+            StateId = string.IsNullOrWhiteSpace(_inner.Context.StateId) ? request.StateId : _inner.Context.StateId,
+            CorrelationId = string.IsNullOrWhiteSpace(_inner.Context.CorrelationId) ? request.RequestId : _inner.Context.CorrelationId,
+            Metadata = MergeContextMetadata(request)
         };
     }
 
@@ -47,15 +54,40 @@ public GovernedMutation(IMutation<TState> inner, string requestId, string stateI
 
     public MutationResult<TState> Simulate(TState state) => _inner.Simulate(state);
 
-    private static IReadOnlyDictionary<string, object> MergeMetadata(
-        IReadOnlyDictionary<string, object> source,
-        string requestId)
+    private IReadOnlyDictionary<string, object> MergeContextMetadata(MutationRequest request)
     {
-        var metadata = new Dictionary<string, object>(source)
+        var metadata = new Dictionary<string, object>(_inner.Context.Metadata)
         {
-            ["GovernanceRequestId"] = requestId
+            [GovernanceRequestIdMetadataKey] = request.RequestId
         };
 
+        if (request.Metadata.Count > 0)
+            metadata[GovernanceRequestMetadataKey] = request.Metadata;
+
+        if (request.Intent.Metadata.Count > 0)
+            metadata[GovernanceIntentMetadataKey] = request.Intent.Metadata;
+
+        if (request.Intent.EstimatedBlastRadius is not null)
+            metadata[GovernanceEstimatedBlastRadiusMetadataKey] = request.Intent.EstimatedBlastRadius;
+
         return metadata;
     }
+
+    private IReadOnlyDictionary<string, object> MergeIntentMetadata(MutationRequest request)
+    {
+        var metadata = new Dictionary<string, object>(request.Intent.Metadata)
+        {
+            [GovernanceRequestIdMetadataKey] = request.RequestId
+        };
+
+        if (_inner.Intent.Metadata.Count > 0)
+            metadata["ExecutionIntentMetadata"] = _inner.Intent.Metadata;
+
+        return metadata;
+    }
+
+    private static IReadOnlySet<string> MergeTags(
+        IReadOnlySet<string> requestTags,
+        IReadOnlySet<string> executionTags)
+        => new HashSet<string>(requestTags.Concat(executionTags), StringComparer.Ordinal);
 }