DKNet

Compose reusable queries

Part of DKNet.EfCore.Specifications. Replace the Quick Start specification with a mixed-order, bounded read:

public sealed class MinimumPrice : Specification<Product>
{
    public MinimumPrice(int minimum)
    {
        WithFilter(p => p.Price >= minimum);
        AddOrderByDescending(p => p.Price);
        AddOrderBy(p => p.Id);
        AsNoTracking();
        Take(20);
    }
}

A Specification stores its filter, includes and ordered clauses, and ApplySpecs folds them into an IQueryable before applying tracking and offset-window flags.

Derive from Specification<TEntity> and use the protected builders in your constructor. WithFilter replaces the previous FilterQuery; combine predicates yourself when several conditions belong together. CreatePredicate returns a LinqKit starter, optionally initialized with an expression.

AddInclude(Expression<Func<TEntity, object?>>) supports single-navigation and filtered includes. AddInclude(Func<IQueryable<TEntity>, IQueryable<TEntity>>) supports Include/ThenInclude chains and deeper filtering. Ascending and descending order clauses are applied in declaration order as OrderBy followed by ThenBy.

ISpecification<TEntity> exposes FilterQuery, IncludeQueries, IncludeBuilders and IsIgnoreQueryFilters. Ordering, tracking and window state are recognized only on the Specification<TEntity> base. Its copy constructor accepts an existing specification and copies all base state, including flags and windowing when available.

⚙️ Configuration reference

Builder	Type	Default	Effect
`AsNoTracking()`	Flag	Tracking	Read-only entity query.
`IgnoreQueryFilters()`	Flag	`false`	Disable only named filters registered as ignorable.
`Skip(count)` / `Take(count)`	Positive `int`	Unset	Offset/limit applied during query composition; `count <= 0` throws.
`AddOrderBy(name, direction)`	`string`, `ListSortDirection`	No order	Normalize a runtime property name and construct an ordering expression.

There is no options object. A null specification is rejected by query composition.

🧱 Where it fits

The query architecture shows the repository applying these inert declarations. DataAuthorization marks ownership filters non-ignorable, so the specification bypass flag preserves them.

⚠️ Gotchas & limits

ApplySpecs is internal; consumers execute via IRepositorySpec.Query or its public materialization helpers.
A runtime sort name is not the validated dynamic-filter path. Unknown names can throw; dotted paths are not built as chained member access by this ordering overload. Validate sort choices in the caller.
Tracking navigation fixup can reattach previously tracked children outside a filtered include. Use a no-tracking query or projection for exact filtered children.
Reading only FilterQuery ignores includes, ordering and flags. Execute the full specification rather than reconstructing part of it.

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