fix: Use string JSON payloads across oplog and stores

Change Oplog payload representation from JsonElement to string and adapt persistence/network layers accordingly. OplogEntry.Payload is now a string? and callers only deserialize to JsonElement when needed (Document, conflict resolvers). Persisted entities now store normalized JSON strings; BLite/EF stores write payload via GetRawText(). Snapshot, sync handlers, and TCP client now pass JsonData as strings. EntityMappers adds ComputeContentHash(string?) and CreateDocumentMetadata helpers for string content. Tests updated to use string payloads. Also bump BLite packages to 4.3.1.

Author: mrdevrobot

samples/EntglDb.Demo.Game/EntglDb.Demo.Game.csproj

@@ -15,8 +15,8 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="BLite" Version="4.3.0" />
-    <PackageReference Include="BLite.SourceGenerators" Version="4.3.0">
+    <PackageReference Include="BLite" Version="4.3.1" />
+    <PackageReference Include="BLite.SourceGenerators" Version="4.3.1">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>

samples/EntglDb.Sample.Shared/EntglDb.Sample.Shared.csproj

@@ -13,7 +13,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="BLite.SourceGenerators" Version="4.3.0">
+    <PackageReference Include="BLite.SourceGenerators" Version="4.3.1">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>

src/EntglDb.Core/Document.cs

@@ -31,7 +31,7 @@ public void Merge(OplogEntry oplogEntry, IConflictResolver? resolver = null)
             //last wins
             if(UpdatedAt <= oplogEntry.Timestamp)
             {
-                Content = oplogEntry.Payload ?? default;
+                Content = string.IsNullOrEmpty(oplogEntry.Payload) ? default : JsonSerializer.Deserialize<JsonElement>(oplogEntry.Payload);
                 UpdatedAt = oplogEntry.Timestamp;
                 IsDeleted = oplogEntry.Operation == OperationType.Delete;
             }

src/EntglDb.Core/Sync/LastWriteWinsConflictResolver.cs

@@ -11,7 +11,7 @@ public ConflictResolutionResult Resolve(Document? local, OplogEntry remote)
         if (local == null)
         {
             // Construct new document from oplog entry
-            var content = remote.Payload ?? default;
+            var content = string.IsNullOrEmpty(remote.Payload) ? default : JsonSerializer.Deserialize<JsonElement>(remote.Payload);
             var newDoc = new Document(remote.Collection, remote.Key, content, remote.Timestamp, remote.Operation == OperationType.Delete);
             return ConflictResolutionResult.Apply(newDoc);
         }
@@ -20,7 +20,7 @@ public ConflictResolutionResult Resolve(Document? local, OplogEntry remote)
         if (remote.Timestamp.CompareTo(local.UpdatedAt) > 0)
         {
             // Remote is newer, apply it
-            var content = remote.Payload ?? default;
+            var content = string.IsNullOrEmpty(remote.Payload) ? default : JsonSerializer.Deserialize<JsonElement>(remote.Payload);
             var newDoc = new Document(remote.Collection, remote.Key, content, remote.Timestamp, remote.Operation == OperationType.Delete);
             return ConflictResolutionResult.Apply(newDoc);
         }

src/EntglDb.Core/Sync/RecursiveNodeMergeConflictResolver.cs

@@ -26,7 +26,7 @@ public ConflictResolutionResult Resolve(Document? local, OplogEntry remote)
     {
         if (local == null)
         {
-            var content = remote.Payload ?? default;
+            var content = string.IsNullOrEmpty(remote.Payload) ? default : JsonSerializer.Deserialize<JsonElement>(remote.Payload);
             var newDoc = new Document(remote.Collection, remote.Key, content, remote.Timestamp, remote.Operation == OperationType.Delete);
             return ConflictResolutionResult.Apply(newDoc);
         }
@@ -42,7 +42,7 @@ public ConflictResolutionResult Resolve(Document? local, OplogEntry remote)
         }
 
         var localJson = local.Content;
-        var remoteJson = remote.Payload ?? default;
+        var remoteJson = string.IsNullOrEmpty(remote.Payload) ? default : JsonSerializer.Deserialize<JsonElement>(remote.Payload);
         var localTs = local.UpdatedAt;
         var remoteTs = remote.Timestamp;
 

src/EntglDb.Network/CoreTypes/OplogEntry.cs

@@ -1,5 +1,4 @@
 using System;
-using System.Text.Json;
 
 namespace EntglDb.Core;
 
@@ -111,12 +110,12 @@ public class OplogEntry
     public string Collection { get; }
     public string Key { get; }
     public OperationType Operation { get; }
-    public JsonElement? Payload { get; }
+    public string? Payload { get; }
     public HlcTimestamp Timestamp { get; }
     public string Hash { get; }
     public string PreviousHash { get; }
 
-    public OplogEntry(string collection, string key, OperationType operation, JsonElement? payload, HlcTimestamp timestamp, string previousHash, string? hash = null)
+    public OplogEntry(string collection, string key, OperationType operation, string? payload, HlcTimestamp timestamp, string previousHash, string? hash = null)
     {
         Collection = collection;
         Key = key;

src/EntglDb.Persistence.BLite/BLiteDocumentStore.cs

@@ -329,7 +329,7 @@ public async Task<Document> MergeAsync(Document incoming, CancellationToken canc
             incoming.Collection,
             incoming.Key,
             OperationType.Put,
-            incoming.Content,
+            incoming.Content.GetRawText(),
             incoming.UpdatedAt,
             ""));
 

src/EntglDb.Persistence.BLite/EntglDb.Persistence.BLite.csproj

@@ -17,8 +17,8 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="BLite" Version="4.3.0" />
-    <PackageReference Include="BLite.SourceGenerators" Version="4.3.0">
+    <PackageReference Include="BLite" Version="4.3.1" />
+    <PackageReference Include="BLite.SourceGenerators" Version="4.3.1">
       <PrivateAssets>all</PrivateAssets>
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
     </PackageReference>

src/EntglDb.Persistence.BLite/Entities/EntityMappers.cs

@@ -27,7 +27,7 @@ public static OplogEntity ToEntity(this OplogEntry entry)
             Key = entry.Key,
             Operation = (int)entry.Operation,
             // Store normalized (key-sorted) JSON so cross-node payload comparisons are reliable
-            PayloadJson = entry.Payload.HasValue ? NormalizeJson(entry.Payload.Value) : "",
+            PayloadJson = string.IsNullOrEmpty(entry.Payload) ? "" : NormalizeJson(JsonSerializer.Deserialize<JsonElement>(entry.Payload)),
             TimestampPhysicalTime = entry.Timestamp.PhysicalTime,
             TimestampLogicalCounter = entry.Timestamp.LogicalCounter,
             TimestampNodeId = entry.Timestamp.NodeId,
@@ -41,18 +41,11 @@ public static OplogEntity ToEntity(this OplogEntry entry)
     /// </summary>
     public static OplogEntry ToDomain(this OplogEntity entity)
     {
-        JsonElement? payload = null;
-        // Treat empty string as null payload (Delete operations)
-        if (!string.IsNullOrEmpty(entity.PayloadJson))
-        {
-            payload = JsonSerializer.Deserialize<JsonElement>(entity.PayloadJson);
-        }
-
         return new OplogEntry(
             entity.Collection,
             entity.Key,
             (OperationType)entity.Operation,
-            payload,
+            string.IsNullOrEmpty(entity.PayloadJson) ? null : entity.PayloadJson,
             new HlcTimestamp(entity.TimestampPhysicalTime, entity.TimestampLogicalCounter, entity.TimestampNodeId),
             entity.PreviousHash,
             entity.Hash);
@@ -208,6 +201,36 @@ public static string ComputeContentHashFromNormalized(string normalizedJson)
         return Convert.ToHexString(hash).ToLowerInvariant();
     }
 
+    /// <summary>
+    /// Computes a SHA-256 hash of the canonical (key-sorted) JSON representation of a document.
+    /// Returns an empty string for null/empty content (deletes).
+    /// </summary>
+    public static string ComputeContentHash(string? contentJson)
+    {
+        if (string.IsNullOrEmpty(contentJson)) return "";
+        return ComputeContentHash(JsonSerializer.Deserialize<JsonElement>(contentJson));
+    }
+
+    /// <summary>
+    /// Creates a DocumentMetadataEntity from collection, key, timestamp, deleted state, and optional raw JSON content.
+    /// Used for tracking document sync state when content is available as a string.
+    /// </summary>
+    public static DocumentMetadataEntity CreateDocumentMetadata(
+        string collection, string key, HlcTimestamp timestamp, bool isDeleted, string? contentJson)
+    {
+        return new DocumentMetadataEntity
+        {
+            Id = $"{collection}/{key}",
+            Collection = collection,
+            Key = key,
+            HlcPhysicalTime = timestamp.PhysicalTime,
+            HlcLogicalCounter = timestamp.LogicalCounter,
+            HlcNodeId = timestamp.NodeId,
+            IsDeleted = isDeleted,
+            ContentHash = isDeleted ? "" : ComputeContentHash(contentJson)
+        };
+    }
+
     /// <summary>
     /// Computes a SHA-256 hash of the canonical (key-sorted) JSON representation of a document.
     /// Returns an empty string for null content (deletes).

src/EntglDb.Persistence.BLite/PendingChangesFlushService.cs

@@ -90,7 +90,7 @@ private async Task ProcessOneChangeAsync(PendingChange change, CancellationToken
 
         // For Put: read current content from the application document store.
         var operationType = change.OperationType;
-        JsonElement? content = null;
+        string? content = null;
 
         if (operationType == OperationType.Put)
         {
@@ -102,7 +102,7 @@ private async Task ProcessOneChangeAsync(PendingChange change, CancellationToken
             }
             else
             {
-                content = doc.Content;
+                content = doc.Content.GetRawText();
             }
         }