Goldpath.Data 0.1.0-preview.8

Goldpath.Data

Data-path floor of the Goldpath enterprise asset: the keyset cursor-pagination executor, the save-contributor seam Ring B modules plug into, and money/time-safe model conventions. Provider-neutral — Npgsql/SqlServer/Oracle are wired by the template from the manifest.

Getting started

builder.AddGoldpathData<WebApplicationBuilder, OrdersDbContext>(o => o.UseNpgsql(connectionString));

public class OrdersDbContext : DbContext
{
    protected override void ConfigureConventions(ModelConfigurationBuilder b)
        => b.ApplyGoldpathConventions();          // string 256, decimal 18,4, TenantId conversion

    protected override void OnModelCreating(ModelBuilder b)
        => b.ApplyGoldpathModelDefaults();        // enums stored as strings
}

Configuration

Deliberately minimal — conventions are the configuration. Explicit per-property settings always win over the defaults.

Advanced

Keyset pagination (the executor of the Goldpath.ApiDefaults wire contract — never OFFSET):

Page<OrderDto> page = await db.Orders
    .Where(o => o.Status == OrderStatus.Confirmed)
    .Select(o => new OrderDto(o.Id, o.CreatedAt, ...))
    .ToPageAsync(request, o => o.CreatedAt, o => o.Id, cancellationToken: ct);   // (timestamp, id) canonical pair

• Ordering is applied BY the executor from the key selectors — a mismatched manual order-by (the classic skipped-rows bug) cannot happen.
• Keys must be unique (single) or unique-together (pair). 1–2 keys, per-key direction.
• Projection rule: project with member-init records/types (new Dto { X = o.X }). Positional-constructor projections cannot be traced back to columns by EF, so the keyset ORDER BY fails to translate (found by the golden-path walking skeleton).
• A tampered/invalid cursor throws GoldpathInvalidCursorException → map to HTTP 400 (the golden-path template wires this mapping).

Save-contributor seam (for Ring B modules, not application code): implement IEntitySaveContributor, register it, and every save runs it over Added/Modified/Deleted entries with GoldpathSaveContext (clock + tenant). AuditTrail/SoftDelete/MultiTenancy attach here.

Migrations (RFC D1): Development auto-migrates (template wiring); every other environment applies the CI-produced dotnet ef migrations bundle artifact as an explicit pipeline step. Runtime Migrate() outside Development is forbidden (GP0302).

Providers

Chosen in the manifest (providers.db), wired by the template: postgresql (Npgsql), sqlserver, oracle. This package references only Microsoft.EntityFrameworkCore.Relational.