KeysetEngine

High-performance, database-agnostic keyset pagination and universal search library for .NET 8, .NET 9, and .NET 10 with Entity Framework Core.

Keyset pagination avoids the $O(N)$ execution degradation inherent to SQL OFFSET on deep datasets by establishing stable, indexed boundaries using composite keys and opaque cursors.

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Packages

Package	NuGet	Description
KeysetEngine.Core		Core contracts, expression builders, $N+1$ slicing, universal search, and IQueryable<T> extensions.
KeysetEngine.DataProtection		Cryptographic ASP.NET Core Data Protection cursor tokens with purpose isolation.
KeysetEngine.PostgreSql		PostgreSQL search adapter with EF.Functions.ILike and tsvector full-text search.
KeysetEngine.SqlServer		SQL Server search adapter with EF.Functions.FreeText / CONTAINS and collation strategies.

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Features

• True $O(1)$ Keyset Pagination: No slow OFFSET scans; uses nested boolean comparison trees compatible with SQL Server, PostgreSQL, and SQLite.
• Bidirectional Traversal: Seamless forward and backward page navigation with automated in-memory ordering reversal.
• Tamper-Proof Opaque Cursors: Cryptographic protection via ASP.NET Core Data Protection with purpose and entity isolation.
• Dynamic Multi-Column Search: Search across multiple properties without breaking keyset boundaries or client-side evaluation.
• Multi-Targeting Support: Native support for modern LTS and Current .NET runtimes (net8.0, net9.0, net10.0).

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Quickstart

1. Register Services

// In Program.cs / Startup.cs
builder.Services.AddKeysetPagination();

// Optional: Register database-specific search strategy
builder.Services.AddKeysetPostgreSqlSearch(); // or AddKeysetSqlServerSearch()

2. Configure Entity Keyset

var config = new KeysetConfigBuilder<Order>()
    .SortBy(x => x.CreatedAt, ascending: false)
    .TieBreakBy(x => x.Id)
    .SearchIn(x => x.CustomerName, x => x.OrderNumber)
    .Build();

3. Query Paginated Data

app.MapGet("/orders", async (
    [AsParameters] KeysetRequest request,
    AppDbContext db,
    ICursorProtector protector,
    CancellationToken ct) =>
{
    var page = await db.Orders
        .AsNoTracking()
        .ToKeysetPageAsync(request, config, protector, ct);

    return Results.Ok(page);
});

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Semantic Versioning & Releases

KeysetEngine adheres strictly to Semantic Versioning 2.0.0. Releases and packages are tagged and published automatically using MinVer and NuGet Trusted Publishing (OIDC).

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License

This project is licensed under the MIT License.