Aspire with MongoDB and EFCore

[JohnnyDevCraft]

I'm trying to get EFCore running with MongoDB in Aspire, but I'm hitting a wall.

First, It took some digging to figure out compatible versions:

  <ItemGroup>
      <PackageReference Include="Aspire.MongoDB.Driver" Version="9.1.0" />
        <PackageReference Include="Aspire.Hosting.Redis" Version="9.1.0" />
        <PackageReference Include="MongoDB.Driver" Version="2.30.0" />
        <PackageReference Include="MongoDB.EntityFrameworkCore" Version="8.1.0"/>
        <PackageReference Include="Microsoft.EntityFrameworkCore" Version="8.0.14" />
    </ItemGroup>

Then I had to try and get a context wired up. I have a single entity:

public class Ship
{
    public Guid Id { get; set; }
    public required string Name { get; set; }
    public required string Identifier { get; set; }
    public DateTime DateCreated { get; set; }
    public required string Owner { get; set; }
}

... which is set up in a context using this extension:

public static ModelBuilder AddShipsModel(this ModelBuilder mb)
    {

        mb.Entity<Entities.Ship>(entity =>
        {
            entity.ToCollection("ships");
        });

        return mb;
    }

And this is my Context Class:

public class ShipsContext(DbContextOptions<ShipsContext> options) : DbContext(options)
{
    public DbSet<Entities.Ship> Ships { get; init; }

 

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        base.OnModelCreating(modelBuilder);
        modelBuilder.AddShipsModel();
    }
}

All of this is utilizing Aspire for Connection Strings, and my builder code looks like this:

public static void AddShipsMigration(this HostApplicationBuilder? builder)
{
    if(builder is null) return;
    builder.AddMongoDBClient(Defaults.ShipModule.ShipsDb);
    builder.Services.AddScoped(sp =>
    {
        var  logger = sp.GetRequiredService<ILogger<ShipsContext>>();
        logger.LogInformation("Creating ShipsContext");
        var client = sp.GetRequiredService<IMongoClient>();
        logger.LogInformation("Got MongoClient with databases: {databases}", string.Join(", ", client.ListDatabaseNames().ToList()));
        var db = client.GetDatabase(Defaults.ShipModule.ShipsDb);
        logger.LogInformation("Got database {database}", db.DatabaseNamespace.DatabaseName);
        
        var options = new DbContextOptionsBuilder<ShipsContext>()
            .UseMongoDB(db.Client, db.DatabaseNamespace.DatabaseName)
            .Options;
        logger.LogInformation("Created options, now adding context.");
        return new ShipsContext(options);
    });
    
    MigratorExtensions.AddMigrationApplicator(MigrateDatabase);
}

private static void MigrateDatabase(IServiceProvider obj)
{
    var context = obj.GetRequiredService<ShipsContext>();
    context.Database.EnsureCreated();
}

I can get the IMongoClient and the database, but when I call Ensure created it gives me the following error message:

Method not found: 'Void Microsoft.EntityFrameworkCore.Metadata.Conventions.RelationshipDiscoveryConvention..ctor(Microsoft.EntityFrameworkCore.Metadata.Conventions.Infrastructure.ProviderConventionSetBuilderDependencies)'.

I can't figure out what's causing the issue and I would love some advice.

[eyjolfurgudnivatne]

Maybe this can help?

• References:

  <ItemGroup>
	  <PackageReference Include="Aspire.MongoDB.Driver.v3" Version="9.2.0" />
	  <PackageReference Include="Microsoft.AspNetCore.OpenApi" Version="9.0.4" />
	  <PackageReference Include="MongoDB.EntityFrameworkCore" Version="8.2.3" />
  </ItemGroup>

• MyDbContext:

public class MyDbContext(DbContextOptions<MyDbContext> options) : DbContext(options)
{
    public DbSet<MyCakes> MyCakes { get; init; }

    // https://www.mongodb.com/docs/entity-framework/current/fundamentals/indexes/
    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        base.OnModelCreating(modelBuilder);

        modelBuilder.Entity<MyCakes>(p =>
        {
            p.HasIndex(x => x.TasteScore);
            p.ToCollection("mycakes");
        });
    }
}

• Program.cs:

...

const string databaseName = "mydb";

// register IMongoClient and IMongoDatabase instances
builder.AddMongoDBClient(databaseName);

// register DbContext
// blazor? use factory: https://learn.microsoft.com/nb-no/ef/core/dbcontext-configuration/#use-a-dbcontext-factory
builder.Services.AddDbContext<MyDbContext>((sp, dbBuilder) =>
    dbBuilder.UseMongoDB(sp.GetRequiredService<IMongoClient>(), databaseName));

var app = builder.Build();

// trigger OnModelCreating in MyDbContext
using var scope = app.Services.CreateScope();
var db = scope.ServiceProvider.GetRequiredService<MyDbContext>();
await db.Database.EnsureCreatedAsync();

...

app.MapGroup("/cakes").MapCakeEndpoints();

• Api:

internal static class CakeEndpoints
{
    public static RouteGroupBuilder MapCakeEndpoints(this RouteGroupBuilder group)
    {
        group.MapGet("", GetCakes)
            .WithName("GetCakes")
            .Produces<MyCakes[]>(StatusCodes.Status200OK);

        return group;
    }

    public static async Task<IResult> GetCakes(MyDbContext db)
    {
        var cakes = await db.MyCakes.AsNoTracking().ToListAsync();
        return Results.Ok(cakes);
    }
}