Registering a LocalDb instance via MS DI.

RegisterLocalDb.cs

static void RegisterDbContext<TContext>(IServiceCollection services)
        where TContext : DbContext
{
    services.AddSingleton<SqlInstance<TContext>>(p => new SqlInstance<TContext>(builder => (TContext)ActivatorUtilities.CreateInstance<TContext>(p, builder.Options)));

    services.AddScoped<SqlDatabase<TContext>>(p =>
    {
        SqlInstance<TContext> sqlInstance = p.GetRequiredService<SqlInstance<TContext>>();

        // Safe excecution of async via dedicated factory and unwrapping.
        return RunSync(() => sqlInstance.Build(typeof(TContext).Name));
    });

    services.AddScoped<TContext>(p =>
    {
        SqlDatabase<TContext> database = p.GetRequiredService<SqlDatabase<TContext>>();
        return database.NewDbContext();
    });
}

sorry for the delay

SqlInstance maps to a sql server instance. it should be called once per appdomain. so eg in a module init, in a static ctor of a test base class, in a testfixture global [startup]. i find the static ctor of a test base class to be the most common since u only pay the startup cost on test that use the db. so if u run a non-db test in isolation, the db interaction wont inpact it.

it is a unique db per test method. they are not cleaned up, but left running after a test so u can debug the db instance if necessary. u can opt in to delete the db https://github.com/SimonCropp/LocalDb/blob/master/src/LocalDb/SqlDatabase.cs#L55

Database files older than a day will be purged from the data directory.