Fixed the number of resource definition callbacks for sparse fieldsets

Author: Bart Koelman

benchmarks/Serialization/JsonApiSerializerBenchmarks.cs

@@ -3,6 +3,7 @@
 using JsonApiDotNetCore.Configuration;
 using JsonApiDotNetCore.Middleware;
 using JsonApiDotNetCore.Queries;
+using JsonApiDotNetCore.Queries.Internal;
 using JsonApiDotNetCore.QueryStrings.Internal;
 using JsonApiDotNetCore.Resources;
 using JsonApiDotNetCore.Serialization;
@@ -27,33 +28,29 @@ public class JsonApiSerializerBenchmarks
         public JsonApiSerializerBenchmarks()
         {
             var options = new JsonApiOptions();
+            var request = new JsonApiRequest();
+
             IResourceGraph resourceGraph = _dependencyFactory.CreateResourceGraph(options);
-            IFieldsToSerialize fieldsToSerialize = CreateFieldsToSerialize(resourceGraph);
+
+            var constraintProviders = new IQueryConstraintProvider[]
+            {
+                new SparseFieldSetQueryStringParameterReader(request, resourceGraph)
+            };
+
+            IResourceDefinitionAccessor resourceDefinitionAccessor = new Mock<IResourceDefinitionAccessor>().Object;
+            var sparseFieldSetCache = new SparseFieldSetCache(constraintProviders, resourceDefinitionAccessor);
 
             IMetaBuilder metaBuilder = new Mock<IMetaBuilder>().Object;
             ILinkBuilder linkBuilder = new Mock<ILinkBuilder>().Object;
             IIncludedResourceObjectBuilder includeBuilder = new Mock<IIncludedResourceObjectBuilder>().Object;
 
-            var resourceObjectBuilder = new ResourceObjectBuilder(resourceGraph, options);
+            IFieldsToSerialize fieldsToSerialize =
+                new FieldsToSerialize(resourceGraph, constraintProviders, resourceDefinitionAccessor, request, sparseFieldSetCache);
 
-            IResourceDefinitionAccessor resourceDefinitionAccessor = new Mock<IResourceDefinitionAccessor>().Object;
+            var resourceObjectBuilder = new ResourceObjectBuilder(resourceGraph, options);
 
             _jsonApiSerializer = new ResponseSerializer<BenchmarkResource>(metaBuilder, linkBuilder, includeBuilder, fieldsToSerialize, resourceObjectBuilder,
-                resourceDefinitionAccessor, options);
-        }
-
-        private static FieldsToSerialize CreateFieldsToSerialize(IResourceGraph resourceGraph)
-        {
-            var request = new JsonApiRequest();
-
-            var constraintProviders = new IQueryConstraintProvider[]
-            {
-                new SparseFieldSetQueryStringParameterReader(request, resourceGraph)
-            };
-
-            IResourceDefinitionAccessor accessor = new Mock<IResourceDefinitionAccessor>().Object;
-
-            return new FieldsToSerialize(resourceGraph, constraintProviders, accessor, request);
+                resourceDefinitionAccessor, sparseFieldSetCache, options);
         }
 
         [Benchmark]

src/JsonApiDotNetCore/AtomicOperations/OperationsProcessor.cs

@@ -1,12 +1,12 @@
 using System;
 using System.Collections.Generic;
-using System.Net;
 using System.Threading;
 using System.Threading.Tasks;
 using JetBrains.Annotations;
 using JsonApiDotNetCore.Configuration;
 using JsonApiDotNetCore.Errors;
 using JsonApiDotNetCore.Middleware;
+using JsonApiDotNetCore.Queries.Internal;
 using JsonApiDotNetCore.Resources;
 using JsonApiDotNetCore.Serialization.Objects;
 
@@ -22,24 +22,28 @@ public class OperationsProcessor : IOperationsProcessor
         private readonly IResourceGraph _resourceGraph;
         private readonly IJsonApiRequest _request;
         private readonly ITargetedFields _targetedFields;
+        private readonly ISparseFieldSetCache _sparseFieldSetCache;
         private readonly LocalIdValidator _localIdValidator;
 
         public OperationsProcessor(IOperationProcessorAccessor operationProcessorAccessor, IOperationsTransactionFactory operationsTransactionFactory,
-            ILocalIdTracker localIdTracker, IResourceGraph resourceGraph, IJsonApiRequest request, ITargetedFields targetedFields)
+            ILocalIdTracker localIdTracker, IResourceGraph resourceGraph, IJsonApiRequest request, ITargetedFields targetedFields,
+            ISparseFieldSetCache sparseFieldSetCache)
         {
             ArgumentGuard.NotNull(operationProcessorAccessor, nameof(operationProcessorAccessor));
             ArgumentGuard.NotNull(operationsTransactionFactory, nameof(operationsTransactionFactory));
             ArgumentGuard.NotNull(localIdTracker, nameof(localIdTracker));
             ArgumentGuard.NotNull(resourceGraph, nameof(resourceGraph));
             ArgumentGuard.NotNull(request, nameof(request));
             ArgumentGuard.NotNull(targetedFields, nameof(targetedFields));
+            ArgumentGuard.NotNull(sparseFieldSetCache, nameof(sparseFieldSetCache));
 
             _operationProcessorAccessor = operationProcessorAccessor;
             _operationsTransactionFactory = operationsTransactionFactory;
             _localIdTracker = localIdTracker;
             _resourceGraph = resourceGraph;
             _request = request;
             _targetedFields = targetedFields;
+            _sparseFieldSetCache = sparseFieldSetCache;
             _localIdValidator = new LocalIdValidator(_localIdTracker, _resourceGraph);
         }
 
@@ -67,6 +71,8 @@ public virtual async Task<IList<OperationContainer>> ProcessAsync(IList<Operatio
                     results.Add(result);
 
                     await transaction.AfterProcessOperationAsync(cancellationToken);
+
+                    _sparseFieldSetCache.Reset();
                 }
 
                 await transaction.CommitAsync(cancellationToken);

src/JsonApiDotNetCore/Configuration/JsonApiApplicationBuilder.cs

@@ -157,6 +157,7 @@ public void ConfigureServiceContainer(ICollection<Type> dbContextTypes)
             _services.AddScoped(typeof(IResourceChangeTracker<>), typeof(ResourceChangeTracker<>));
             _services.AddScoped<IPaginationContext, PaginationContext>();
             _services.AddScoped<IEvaluatedIncludeCache, EvaluatedIncludeCache>();
+            _services.AddScoped<ISparseFieldSetCache, SparseFieldSetCache>();
             _services.AddScoped<IQueryLayerComposer, QueryLayerComposer>();
             _services.AddScoped<IInverseNavigationResolver, InverseNavigationResolver>();
         }

src/JsonApiDotNetCore/Queries/Internal/ISparseFieldSetCache.cs

@@ -0,0 +1,40 @@
+using System.Collections.Immutable;
+using JsonApiDotNetCore.Configuration;
+using JsonApiDotNetCore.Resources;
+using JsonApiDotNetCore.Resources.Annotations;
+
+namespace JsonApiDotNetCore.Queries.Internal
+{
+    /// <summary>
+    /// Takes sparse fieldsets from <see cref="IQueryConstraintProvider" />s and invokes
+    /// <see cref="IResourceDefinition{TResource,TId}.OnApplySparseFieldSet" /> on them.
+    /// </summary>
+    /// <remarks>
+    /// This cache ensures that for each request (or operation per request), the resource definition callback is executed only twice per resource type. The
+    /// first invocation is used to obtain the fields to retrieve from the underlying data store, while the second invocation is used to determine which
+    /// fields to write to the response body.
+    /// </remarks>
+    public interface ISparseFieldSetCache
+    {
+        /// <summary>
+        /// Gets the set of sparse fields to retrieve from the underlying data store. Returns an empty set to retrieve all fields.
+        /// </summary>
+        IImmutableSet<ResourceFieldAttribute> GetSparseFieldSetForQuery(ResourceContext resourceContext);
+
+        /// <summary>
+        /// Gets the set of attributes to retrieve from the underlying data store for relationship endpoints. This always returns 'id', along with any additional
+        /// attributes from resource definition callback.
+        /// </summary>
+        IImmutableSet<AttrAttribute> GetIdAttributeSetForRelationshipQuery(ResourceContext resourceContext);
+
+        /// <summary>
+        /// Gets the evaluated set of sparse fields to serialize into the response body.
+        /// </summary>
+        IImmutableSet<ResourceFieldAttribute> GetSparseFieldSetForSerializer(ResourceContext resourceContext);
+
+        /// <summary>
+        /// Resets the cached results from resource definition callbacks.
+        /// </summary>
+        void Reset();
+    }
+}

src/JsonApiDotNetCore/Queries/Internal/QueryLayerComposer.cs

@@ -23,11 +23,11 @@ public class QueryLayerComposer : IQueryLayerComposer
         private readonly IPaginationContext _paginationContext;
         private readonly ITargetedFields _targetedFields;
         private readonly IEvaluatedIncludeCache _evaluatedIncludeCache;
-        private readonly SparseFieldSetCache _sparseFieldSetCache;
+        private readonly ISparseFieldSetCache _sparseFieldSetCache;
 
         public QueryLayerComposer(IEnumerable<IQueryConstraintProvider> constraintProviders, IResourceGraph resourceGraph,
             IResourceDefinitionAccessor resourceDefinitionAccessor, IJsonApiOptions options, IPaginationContext paginationContext,
-            ITargetedFields targetedFields, IEvaluatedIncludeCache evaluatedIncludeCache)
+            ITargetedFields targetedFields, IEvaluatedIncludeCache evaluatedIncludeCache, ISparseFieldSetCache sparseFieldSetCache)
         {
             ArgumentGuard.NotNull(constraintProviders, nameof(constraintProviders));
             ArgumentGuard.NotNull(resourceGraph, nameof(resourceGraph));
@@ -36,6 +36,7 @@ public QueryLayerComposer(IEnumerable<IQueryConstraintProvider> constraintProvid
             ArgumentGuard.NotNull(paginationContext, nameof(paginationContext));
             ArgumentGuard.NotNull(targetedFields, nameof(targetedFields));
             ArgumentGuard.NotNull(evaluatedIncludeCache, nameof(evaluatedIncludeCache));
+            ArgumentGuard.NotNull(sparseFieldSetCache, nameof(sparseFieldSetCache));
 
             _constraintProviders = constraintProviders;
             _resourceGraph = resourceGraph;
@@ -44,7 +45,7 @@ public QueryLayerComposer(IEnumerable<IQueryConstraintProvider> constraintProvid
             _paginationContext = paginationContext;
             _targetedFields = targetedFields;
             _evaluatedIncludeCache = evaluatedIncludeCache;
-            _sparseFieldSetCache = new SparseFieldSetCache(_constraintProviders, resourceDefinitionAccessor);
+            _sparseFieldSetCache = sparseFieldSetCache;
         }
 
         /// <inheritdoc />

src/JsonApiDotNetCore/Queries/Internal/SparseFieldSetCache.cs

@@ -2,20 +2,15 @@
 using System.Collections.Generic;
 using System.Collections.Immutable;
 using System.Linq;
-using JetBrains.Annotations;
 using JsonApiDotNetCore.Configuration;
 using JsonApiDotNetCore.Queries.Expressions;
 using JsonApiDotNetCore.Resources;
 using JsonApiDotNetCore.Resources.Annotations;
 
 namespace JsonApiDotNetCore.Queries.Internal
 {
-    /// <summary>
-    /// Takes sparse fieldsets from <see cref="IQueryConstraintProvider" />s and invokes
-    /// <see cref="IResourceDefinition{TResource,TId}.OnApplySparseFieldSet" /> on them.
-    /// </summary>
-    [PublicAPI]
-    public sealed class SparseFieldSetCache
+    /// <inheritdoc />
+    public sealed class SparseFieldSetCache : ISparseFieldSetCache
     {
         private readonly IResourceDefinitionAccessor _resourceDefinitionAccessor;
         private readonly Lazy<IDictionary<ResourceContext, IImmutableSet<ResourceFieldAttribute>>> _lazySourceTable;
@@ -73,6 +68,7 @@ private static void AddSparseFieldsToSet(IImmutableSet<ResourceFieldAttribute> s
             }
         }
 
+        /// <inheritdoc />
         public IImmutableSet<ResourceFieldAttribute> GetSparseFieldSetForQuery(ResourceContext resourceContext)
         {
             ArgumentGuard.NotNull(resourceContext, nameof(resourceContext));
@@ -95,6 +91,7 @@ public IImmutableSet<ResourceFieldAttribute> GetSparseFieldSetForQuery(ResourceC
             return _visitedTable[resourceContext];
         }
 
+        /// <inheritdoc />
         public IImmutableSet<AttrAttribute> GetIdAttributeSetForRelationshipQuery(ResourceContext resourceContext)
         {
             ArgumentGuard.NotNull(resourceContext, nameof(resourceContext));
@@ -113,6 +110,7 @@ public IImmutableSet<AttrAttribute> GetIdAttributeSetForRelationshipQuery(Resour
             return outputAttributes;
         }
 
+        /// <inheritdoc />
         public IImmutableSet<ResourceFieldAttribute> GetSparseFieldSetForSerializer(ResourceContext resourceContext)
         {
             ArgumentGuard.NotNull(resourceContext, nameof(resourceContext));

src/JsonApiDotNetCore/Serialization/AtomicOperationsResponseSerializer.cs

@@ -23,6 +23,7 @@ public sealed class AtomicOperationsResponseSerializer : BaseSerializer, IJsonAp
         private readonly IFieldsToSerialize _fieldsToSerialize;
         private readonly IResourceDefinitionAccessor _resourceDefinitionAccessor;
         private readonly IEvaluatedIncludeCache _evaluatedIncludeCache;
+        private readonly ISparseFieldSetCache _sparseFieldSetCache;
         private readonly IJsonApiRequest _request;
         private readonly IJsonApiOptions _options;
 
@@ -31,14 +32,15 @@ public sealed class AtomicOperationsResponseSerializer : BaseSerializer, IJsonAp
 
         public AtomicOperationsResponseSerializer(IResourceObjectBuilder resourceObjectBuilder, IMetaBuilder metaBuilder, ILinkBuilder linkBuilder,
             IFieldsToSerialize fieldsToSerialize, IResourceDefinitionAccessor resourceDefinitionAccessor, IEvaluatedIncludeCache evaluatedIncludeCache,
-            IJsonApiRequest request, IJsonApiOptions options)
+            ISparseFieldSetCache sparseFieldSetCache, IJsonApiRequest request, IJsonApiOptions options)
             : base(resourceObjectBuilder)
         {
             ArgumentGuard.NotNull(metaBuilder, nameof(metaBuilder));
             ArgumentGuard.NotNull(linkBuilder, nameof(linkBuilder));
             ArgumentGuard.NotNull(fieldsToSerialize, nameof(fieldsToSerialize));
             ArgumentGuard.NotNull(resourceDefinitionAccessor, nameof(resourceDefinitionAccessor));
             ArgumentGuard.NotNull(evaluatedIncludeCache, nameof(evaluatedIncludeCache));
+            ArgumentGuard.NotNull(sparseFieldSetCache, nameof(sparseFieldSetCache));
             ArgumentGuard.NotNull(request, nameof(request));
             ArgumentGuard.NotNull(options, nameof(options));
 
@@ -47,6 +49,7 @@ public AtomicOperationsResponseSerializer(IResourceObjectBuilder resourceObjectB
             _fieldsToSerialize = fieldsToSerialize;
             _resourceDefinitionAccessor = resourceDefinitionAccessor;
             _evaluatedIncludeCache = evaluatedIncludeCache;
+            _sparseFieldSetCache = sparseFieldSetCache;
             _request = request;
             _options = options;
         }
@@ -117,7 +120,7 @@ private AtomicResultObject SerializeOperation(OperationContainer operation)
             if (operation != null)
             {
                 _request.CopyFrom(operation.Request);
-                _fieldsToSerialize.ResetCache();
+                _sparseFieldSetCache.Reset();
                 _evaluatedIncludeCache.Set(null);
 
                 _resourceDefinitionAccessor.OnSerialize(operation.Resource);

src/JsonApiDotNetCore/Serialization/Building/IncludedResourceObjectBuilder.cs

@@ -22,25 +22,26 @@ public class IncludedResourceObjectBuilder : ResourceObjectBuilder, IIncludedRes
         private readonly ILinkBuilder _linkBuilder;
         private readonly IResourceDefinitionAccessor _resourceDefinitionAccessor;
         private readonly IRequestQueryStringAccessor _queryStringAccessor;
-        private readonly SparseFieldSetCache _sparseFieldSetCache;
+        private readonly ISparseFieldSetCache _sparseFieldSetCache;
 
         public IncludedResourceObjectBuilder(IFieldsToSerialize fieldsToSerialize, ILinkBuilder linkBuilder, IResourceGraph resourceGraph,
             IEnumerable<IQueryConstraintProvider> constraintProviders, IResourceDefinitionAccessor resourceDefinitionAccessor,
-            IRequestQueryStringAccessor queryStringAccessor, IJsonApiOptions options)
+            IRequestQueryStringAccessor queryStringAccessor, IJsonApiOptions options, ISparseFieldSetCache sparseFieldSetCache)
             : base(resourceGraph, options)
         {
             ArgumentGuard.NotNull(fieldsToSerialize, nameof(fieldsToSerialize));
             ArgumentGuard.NotNull(linkBuilder, nameof(linkBuilder));
             ArgumentGuard.NotNull(constraintProviders, nameof(constraintProviders));
             ArgumentGuard.NotNull(resourceDefinitionAccessor, nameof(resourceDefinitionAccessor));
             ArgumentGuard.NotNull(queryStringAccessor, nameof(queryStringAccessor));
+            ArgumentGuard.NotNull(sparseFieldSetCache, nameof(sparseFieldSetCache));
 
             _included = new HashSet<ResourceObject>(ResourceIdentityComparer.Instance);
             _fieldsToSerialize = fieldsToSerialize;
             _linkBuilder = linkBuilder;
             _resourceDefinitionAccessor = resourceDefinitionAccessor;
             _queryStringAccessor = queryStringAccessor;
-            _sparseFieldSetCache = new SparseFieldSetCache(constraintProviders, resourceDefinitionAccessor);
+            _sparseFieldSetCache = sparseFieldSetCache;
         }
 
         /// <inheritdoc />

src/JsonApiDotNetCore/Serialization/Building/ResponseResourceObjectBuilder.cs

@@ -21,26 +21,27 @@ public class ResponseResourceObjectBuilder : ResourceObjectBuilder
         private readonly IIncludedResourceObjectBuilder _includedBuilder;
         private readonly IResourceDefinitionAccessor _resourceDefinitionAccessor;
         private readonly IEvaluatedIncludeCache _evaluatedIncludeCache;
-        private readonly SparseFieldSetCache _sparseFieldSetCache;
+        private readonly ISparseFieldSetCache _sparseFieldSetCache;
 
         private RelationshipAttribute _requestRelationship;
 
         public ResponseResourceObjectBuilder(ILinkBuilder linkBuilder, IIncludedResourceObjectBuilder includedBuilder,
             IEnumerable<IQueryConstraintProvider> constraintProviders, IResourceGraph resourceGraph, IResourceDefinitionAccessor resourceDefinitionAccessor,
-            IJsonApiOptions options, IEvaluatedIncludeCache evaluatedIncludeCache)
+            IJsonApiOptions options, IEvaluatedIncludeCache evaluatedIncludeCache, ISparseFieldSetCache sparseFieldSetCache)
             : base(resourceGraph, options)
         {
             ArgumentGuard.NotNull(linkBuilder, nameof(linkBuilder));
             ArgumentGuard.NotNull(includedBuilder, nameof(includedBuilder));
             ArgumentGuard.NotNull(constraintProviders, nameof(constraintProviders));
             ArgumentGuard.NotNull(resourceDefinitionAccessor, nameof(resourceDefinitionAccessor));
             ArgumentGuard.NotNull(evaluatedIncludeCache, nameof(evaluatedIncludeCache));
+            ArgumentGuard.NotNull(sparseFieldSetCache, nameof(sparseFieldSetCache));
 
             _linkBuilder = linkBuilder;
             _includedBuilder = includedBuilder;
             _resourceDefinitionAccessor = resourceDefinitionAccessor;
             _evaluatedIncludeCache = evaluatedIncludeCache;
-            _sparseFieldSetCache = new SparseFieldSetCache(constraintProviders, resourceDefinitionAccessor);
+            _sparseFieldSetCache = sparseFieldSetCache;
         }
 
         public RelationshipObject Build(IIdentifiable resource, RelationshipAttribute requestRelationship)