Changelog v3.4.6 (2025-01-21)

Version 3.4.6 (2025-01-21)

Full Changelog

Endpoint Execution Performance Optimizations

Reduced memory allocations and CPU overhead in the hot path of endpoint execution through several optimizations:

StringBuilder Pooling

Added a thread-safe StringBuilderPool to reuse StringBuilder instances across requests instead of allocating new ones:

• cmdLog - command logging
• cacheKeys - cache key building
• rowBuilder - response row building
• compositeFieldBuffer - nested JSON composite handling
• commandTextBuilder - SQL command text building

The pool maintains up to 64 instances with lock-free rent/return operations.

Avoid Query String Dictionary Allocation

Changed from context.Request.Query.ToDictionary() to using IQueryCollection directly, eliminating a dictionary allocation on every request. The IQueryCollection interface already provides TryGetValue(), Count, and ContainsKey() methods.

StringBuilder for Command Text Building

Replaced ~18 string.Concat(commandText, ...) calls with StringBuilder.Append() operations, reducing intermediate string allocations when building SQL commands for non-formattable routines.

HashSet for Path Parameter Lookup

Added FindMatchingPathParameter() method with lazy-initialized HashSet<string> for O(1) case-insensitive lookups instead of O(n) array iteration when matching path parameters.

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Comprehensive CancellationToken Propagation

Improved cancellation token propagation throughout the entire request pipeline. The CancellationToken parameter is now properly passed to all async operations, enabling proper request cancellation and resource cleanup when clients disconnect or requests are aborted.

Changes:

• NpgsqlRestEndpoint: Fixed missing cancellation token propagation to ReadToEndAsync, ReadAsync, WriteAsync, FlushAsync, BeginTransactionAsync, CommitAsync, and helper methods (PrepareCommand, OpenConnectionAsync, ValidateParametersAsync, ReturnErrorAsync).

• Auth Handlers: Added CancellationToken parameter to BasicAuthHandler.HandleAsync, LoginHandler.HandleAsync, and LogoutHandler.HandleAsync. All database operations and response writes now respect cancellation.

• Upload Handlers: Updated IUploadHandler.UploadAsync interface and all implementations (DefaultUploadHandler, FileSystemUploadHandler, LargeObjectUploadHandler, CsvUploadHandler, ExcelUploadHandler) to accept and propagate cancellation tokens to file I/O and database operations.

• Proxy Handler: Added CancellationToken parameter to ProxyRequestHandler.WriteResponseAsync for cancellable response body writes.

Benefits:

• Immediate cleanup when HTTP clients disconnect mid-request
• Proper cancellation of long-running database queries
• Reduced resource consumption from abandoned requests
• Better handling of upload/download operations that can be cancelled
• Prevents request storms: When users repeatedly refresh the browser during slow endpoint execution, each refresh creates a new request while the previous one continues running. Without proper cancellation token propagation, these abandoned requests continue executing database queries, potentially choking the database. With this fix, abandoned requests are properly cancelled, freeing up database connections immediately.

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