Add CultMesh document registry helpers

src/GameCult.Mesh/CultMeshDocumentRegistries.cs

@@ -0,0 +1,111 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using GameCult.Caching;
+using GameCult.Networking;
+
+namespace GameCult.Mesh
+{
+    public static partial class CultMesh
+    {
+        /// <summary>
+        /// Creates a CultCache document registry and resolves the supplied document types into it.
+        /// </summary>
+        public static CultDocumentRegistry CreateCultCacheDocumentRegistry(params Type[] documentTypes)
+        {
+            return CreateCultCacheDocumentRegistry((IEnumerable<Type>)documentTypes);
+        }
+
+        /// <summary>
+        /// Creates a CultCache document registry and resolves the supplied document types into it.
+        /// </summary>
+        public static CultDocumentRegistry CreateCultCacheDocumentRegistry(IEnumerable<Type> documentTypes)
+        {
+            if (documentTypes == null)
+            {
+                throw new ArgumentNullException(nameof(documentTypes));
+            }
+
+            var registry = new CultDocumentRegistry();
+            foreach (var documentType in DistinctDocumentTypes(documentTypes))
+            {
+                registry.GetRequired(documentType);
+            }
+
+            return registry;
+        }
+
+        /// <summary>
+        /// Creates a CultNet document registry with default bindings for the supplied document types.
+        /// </summary>
+        public static CultNetDocumentRegistry CreateCultNetDocumentRegistry(params Type[] documentTypes)
+        {
+            return CreateCultNetDocumentRegistry((IEnumerable<Type>)documentTypes);
+        }
+
+        /// <summary>
+        /// Creates a CultNet document registry with default bindings for the supplied document types.
+        /// </summary>
+        public static CultNetDocumentRegistry CreateCultNetDocumentRegistry(IEnumerable<Type> documentTypes)
+        {
+            return CreateCultNetDocumentRegistry(documentTypes, null);
+        }
+
+        /// <summary>
+        /// Creates a CultNet document registry with default bindings for the supplied document types.
+        /// </summary>
+        public static CultNetDocumentRegistry CreateCultNetDocumentRegistry(
+            IEnumerable<Type> documentTypes,
+            CultDocumentRegistry? documents)
+        {
+            if (documentTypes == null)
+            {
+                throw new ArgumentNullException(nameof(documentTypes));
+            }
+
+            documents ??= CreateCultCacheDocumentRegistry(documentTypes);
+            var registry = new CultNetDocumentRegistry(documents);
+            var descriptors = DistinctDocumentTypes(documentTypes)
+                .Select(documentType => documents.GetRequired(documentType))
+                .ToArray();
+            foreach (var descriptorGroup in descriptors.GroupBy(descriptor => descriptor.SchemaId, StringComparer.Ordinal))
+            {
+                foreach (var descriptor in descriptorGroup.Reverse())
+                {
+                    registry.Register(CultNetDocumentBinding.ForDocument(descriptor.DocumentType, documents));
+                }
+            }
+
+            return registry;
+        }
+
+        /// <summary>
+        /// Creates a CultNet document registry with default bindings for the supplied document types.
+        /// </summary>
+        public static CultNetDocumentRegistry CreateCultNetDocumentRegistry(
+            CultDocumentRegistry documents,
+            params Type[] documentTypes)
+        {
+            return CreateCultNetDocumentRegistry(documentTypes, documents);
+        }
+
+        /// <summary>
+        /// Creates a CultNet document registry with default bindings for the supplied document types.
+        /// </summary>
+        public static CultNetDocumentRegistry CreateCultNetDocumentRegistry(
+            CultDocumentRegistry documents,
+            IEnumerable<Type> documentTypes)
+        {
+            return CreateCultNetDocumentRegistry(documentTypes, documents);
+        }
+
+        private static IEnumerable<Type> DistinctDocumentTypes(IEnumerable<Type> documentTypes)
+        {
+            return documentTypes
+                .Select(documentType => documentType ?? throw new ArgumentException(
+                    "Document type collections cannot contain null entries.",
+                    nameof(documentTypes)))
+                .Distinct();
+        }
+    }
+}

src/GameCult.Networking/CultNetDocumentRegistry.cs

@@ -94,6 +94,42 @@ namespace GameCult.Networking
                     ? payloadDeserializer(payload)
                     : CultDocumentMessagePackSerialization.Deserialize<T>(payload));
         }
+
+        /// <summary>
+        /// Creates a document binding for a CultCache document type discovered at runtime.
+        /// </summary>
+        public static CultNetDocumentBinding ForDocument(
+            Type documentType,
+            CultDocumentRegistry? registry = null,
+            string? schemaId = null,
+            Func<object, byte[]>? payloadSerializer = null,
+            Func<byte[], object>? payloadDeserializer = null)
+        {
+            if (documentType == null)
+            {
+                throw new ArgumentNullException(nameof(documentType));
+            }
+
+            var descriptor = (registry ?? CultDocumentRegistry.Shared).GetRequired(documentType);
+            return new CultNetDocumentBinding(
+                documentType,
+                string.IsNullOrWhiteSpace(schemaId) ? descriptor.SchemaId : schemaId!,
+                document =>
+                {
+                    if (!documentType.IsInstanceOfType(document))
+                    {
+                        throw new InvalidOperationException(
+                            $"Document payload type {document.GetType().FullName} is not assignable to {documentType.FullName}.");
+                    }
+
+                    return payloadSerializer != null
+                        ? payloadSerializer(document)
+                        : CultDocumentMessagePackSerialization.SerializeUntyped(document, documentType);
+                },
+                payload => payloadDeserializer != null
+                    ? payloadDeserializer(payload)
+                    : CultDocumentMessagePackSerialization.DeserializeUntyped(documentType, payload));
+        }
     }
 
     /// <summary>

tests/GameCult.Mesh.Tests/CultMeshStreamingTests.cs

@@ -1101,6 +1101,43 @@ public sealed class CultMeshStreamingTests
             request.MessageId.StartsWith("mesh-test-scoped-snapshot:", StringComparison.Ordinal));
     }
 
+    [Test]
+    public async Task DocumentRegistryHelpers_CreateTypedNetworkRegistriesForAliases()
+    {
+        var sourceCache = new CultCache();
+        var cacheRegistry = CultMesh.CreateCultCacheDocumentRegistry(
+            typeof(MeshNoteDocument),
+            typeof(MeshNoteAliasDocument));
+        var networkRegistry = CultMesh.CreateCultNetDocumentRegistry(
+            new[] { typeof(MeshNoteDocument), typeof(MeshNoteAliasDocument) },
+            cacheRegistry);
+        var key = new CultRecordKey("mesh-note:registry-helper");
+        await sourceCache.UpsertAsync(new MeshNoteDocument
+        {
+            Schema = "tests.mesh_note.v1",
+            Text = "registry-helper",
+            Revision = 23
+        }, new CultRecordHandle<MeshNoteDocument>(key));
+        var endpoint = "cultnet://registry-helper.test:3077";
+
+        var documents = await CultMesh.FetchSnapshotDocumentsAsync<MeshNoteAliasDocument>(
+            endpoint,
+            new CultMeshSnapshotRequestOptions
+            {
+                RecordKeys = new[] { key.Value },
+                CreateClient = () => new MeshSnapshotSchemaClient(request =>
+                    networkRegistry.CreateRawSnapshotResponse(sourceCache, request.MessageId, request))
+            },
+            networkRegistry);
+
+        var schemaId = cacheRegistry.GetRequired<MeshNoteDocument>().SchemaId;
+        cacheRegistry.GetRequired<MeshNoteAliasDocument>().SchemaId.Should().Be(schemaId);
+        networkRegistry.GetByDocumentType(typeof(MeshNoteDocument)).Should().NotBeNull();
+        networkRegistry.GetByDocumentType(typeof(MeshNoteAliasDocument)).Should().NotBeNull();
+        networkRegistry.GetBySchemaId(schemaId)!.DocumentType.Should().Be(typeof(MeshNoteDocument));
+        documents.Should().ContainSingle().Which.Text.Should().Be("registry-helper");
+    }
+
     [Test]
     public async Task SnapshotEndpoint_ProvidesTypedHandlesAndSchemaAliases()
     {