Fix scan pagination (#118)

AllocZero · Apr 13, 2021 · 5cc5cc6 · 5cc5cc6
1 parent 371178f
commit 5cc5cc6
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Showing 3 changed files with 4 additions and 2 deletions.
diff --git a/src/EfficientDynamoDb/Internal/Core/PooledByteBufferWriter.cs b/src/EfficientDynamoDb/Internal/Core/PooledByteBufferWriter.cs
@@ -103,7 +103,6 @@ public void Dispose()
         public void Advance(int count)
         {
             Debug.Assert(_rentedBuffer != null);
-            Debug.Assert(count >= 0);
             Debug.Assert(_index <= _rentedBuffer.Length - count);
 
             _index += count;

diff --git a/src/EfficientDynamoDb/Internal/ErrorHandler.cs b/src/EfficientDynamoDb/Internal/ErrorHandler.cs
@@ -67,7 +67,7 @@ public static async ValueTask ProcessErrorAsync(DynamoDbContextMetadata metadata
                                 "ValidationException" => new ValidationException(error.Message),
                                 "IdempotentParameterMismatchException" => new IdempotentParameterMismatchException(error.Message),
                                 "TransactionInProgressException" => new TransactionInProgressException(error.Message),
-                                _ => new DdbException(error.Message)
+                                _ => new DdbException(error.Message ?? type ?? string.Empty)
                             };
                         case HttpStatusCode.InternalServerError:
                             throw new InternalServerErrorException(error.Message);

diff --git a/src/EfficientDynamoDb/Internal/Extensions/DdbWriterExtensions.cs b/src/EfficientDynamoDb/Internal/Extensions/DdbWriterExtensions.cs
@@ -42,9 +42,12 @@ public static void WritePaginationToken(this DdbWriter writer, string pagination
         {
             writer.JsonWriter.WritePropertyName("ExclusiveStartKey");
 
+            writer.JsonWriter.WriteNullValue();
             // Flush to make sure our changes don't overlap with pending changes
             writer.JsonWriter.Flush();
 
+            // Dirty hack until System.Text.Json supports writing raw json
+            writer.BufferWriter.Advance(-4);
             var bytesSize = Encoding.UTF8.GetByteCount(paginationToken);
 
             var bytesWritten = Encoding.UTF8.GetBytes(paginationToken, writer.BufferWriter.GetSpan(bytesSize));