Expose an entity as a query model

[TraxQueryModel] serves an EF Core entity under discover with paging, filtering, sorting and projection.

Mark your entity with [TraxQueryModel]:

using Trax.Effect.Attributes;
 
[TraxAuthorize] // or [TraxAllowAnonymous]: without a posture the host refuses to start (see Authorization)
[TraxQueryModel(Description = "Player profiles")]
public class PlayerRecord
{
    public long Id { get; set; }
    public string PlayerId { get; set; } = "";
    public string DisplayName { get; set; } = "";
    public int Rating { get; set; }
}

Add the entity to a DbSet<T> on a DbContext:

using Microsoft.EntityFrameworkCore;
 
public class GameDbContext(DbContextOptions<GameDbContext> options) : DbContext(options)
{
    public DbSet<PlayerRecord> Players { get; set; } = null!;
}

using Microsoft.EntityFrameworkCore;
using Trax.Api.GraphQL.Extensions;
 
builder.Services.AddDbContextFactory<GameDbContext>(options =>
    options.UseNpgsql(connectionString));
 
builder.Services.AddTraxGraphQL(graphql =>
    graphql.AddDbContext<GameDbContext>());

For an application's own data, the base to use is a DomainDataContext registered with AddDomainDataContext, and it works here unchanged: AddDbContext<T>() names the concrete context type, and the pooled factory AddDomainDataContext registers serves it.

using Microsoft.EntityFrameworkCore;
using Trax.Effect.Data.Services.DomainContext;
 
public interface IGameDbContext
{
    DbSet<PlayerRecord> Players { get; }
}
 
public class GameDbContext(DbContextOptions<GameDbContext> options)
    : DomainDataContext<GameDbContext>(options), IGameDbContext
{
    public DbSet<PlayerRecord> Players => Set<PlayerRecord>();
    protected override string Schema => "game";
    protected override void ConfigureModel(ModelBuilder modelBuilder) { }
}

using Microsoft.EntityFrameworkCore;
using Trax.Api.GraphQL.Extensions;
using Trax.Effect.Data.Services.DomainContext;
 
builder.Services.AddDomainDataContext<IGameDbContext, GameDbContext>(o => o.UseNpgsql(connectionString));
builder.Services.AddTraxGraphQL(graphql => graphql.AddDbContext<GameDbContext>());

The Bookworm sample serves its catalog this way.

This generates a playerRecords query field under discover:

query {
  discover {
    playerRecords(first: 10, where: { rating: { gte: 1500 } }, order: { rating: DESC }) {
      nodes {
        playerId
        displayName
        rating
      }
      pageInfo {
        hasNextPage
        endCursor
      }
      totalCount
    }
  }
}

SDK Reference

TraxQueryModel | AddTraxGraphQL | TraxAuthorize