C#•2y ago

❔ ✅ AddSingleton and AddDbConnection are not running whatsoever

I have this code

services.AddSingleton<DbConnection>(_ =>
{
    SqliteConnectionStringBuilder stringBuilder = new()
    {
        DataSource = "MemoryDb",
        Mode = SqliteOpenMode.Memory
    };
    SqliteConnection connection = new(stringBuilder.ToString());
    connection.Open();

    return connection;
});

services.AddDbContext<MerpieContext>((serviceProvider, options) =>
{
    var connection = serviceProvider.GetRequiredService<DbConnection>();
    options.UseSqlite(connection, sqliteOptions =>
    {
        sqliteOptions.UseNodaTime();
    });
});

services.AddSingleton<DbConnection>(_ =>
{
    SqliteConnectionStringBuilder stringBuilder = new()
    {
        DataSource = "MemoryDb",
        Mode = SqliteOpenMode.Memory
    };
    SqliteConnection connection = new(stringBuilder.ToString());
    connection.Open();

    return connection;
});

services.AddDbContext<MerpieContext>((serviceProvider, options) =>
{
    var connection = serviceProvider.GetRequiredService<DbConnection>();
    options.UseSqlite(connection, sqliteOptions =>
    {
        sqliteOptions.UseNodaTime();
    });
});

The configuration lambdas are not running. I have no idea why. The DbConnection and MerpieContext are being added to the services, but they're not being configured. I've tried setting breakpoints inside the lambdas but they're never hit.

28 Replies

Tvde1•2y ago

Is the line services.AddSingleton<DbConnection>(_ => hit?

ThinkerOP•2y ago

Yes.

Tvde1•2y ago

are you really calling this method? alright what kind of an instance do you get if DI provides you with a MerpieContext?

ThinkerOP•2y ago

wdym?

Tvde1•2y ago

do you ever request a MerpieContext in a controller or such

ThinkerOP•2y ago

Yes

private void RunMigrations()
{
    using var scope = Services.CreateScope();
    var context = scope.ServiceProvider.GetRequiredService<MerpieContext>();
    
    context.Database.Migrate();
}

private void RunMigrations()
{
    using var scope = Services.CreateScope();
    var context = scope.ServiceProvider.GetRequiredService<MerpieContext>();
    
    context.Database.Migrate();
}

Tvde1•2y ago

and this runs fine?

ThinkerOP•2y ago

Well I get an error on context.Database.Migrate(); that EF can't find the DB file, which I assume is because the connection string is never set. But the first two lines run fine.

Tvde1•2y ago

I suppose you're not accidentally adding MerpieContext to the services somewhere else e.g. a previous configuration I'm not sure what happens if a context is added twice

ThinkerOP•2y ago

Before that I'm actually removing all MerpieContext because this is supposed to replace any previous configuration.

Tvde1•2y ago

as a sanity check, what happens if you run it with services.AddDbContext<MerpieContext>((serviceProvider, options) commented out? hmm And also check whether break points are on. E.g. you're running debug in rider and not just "Run"

ThinkerOP•2y ago

Well other breakpoints are being hit at least

Mayor McCheese•2y ago

Hmm I think I ran into this issue a couple years back and had run an ensure db created method Ultimately I switched over to a file but I forget why

ThinkerOP•2y ago

at this point a file would probably be like lightyears easier lol

Mayor McCheese•2y ago

Oh yeah I remember now why https://stackoverflow.com/questions/56319638/entityframeworkcore-sqlite-in-memory-db-tables-are-not-created I generally don’t bother with SQLite tbh unless it’s really throw away. I know I’m a loner there

ThinkerOP•2y ago

This is exactly what I'm trying to do, as seen above I'm trying to create a connection, but the configuration is not being run Moving the connection stuff outside the configuration lambda does nothing Still getting that exception The file doesn't exist It can't find it But it shouldn't even be looking for a file So the DB is still not being configured BUT WHY Like is this about EF or about MSDI? Is the DI stuff just not working?? Is this some arcane bug that literally no one has reported

phaseshift•2y ago

Suggest: Put only that service registration bit in a service collection in a unit test and verify the behaviour with a minimal example

ThinkerOP•2y ago

Okay. So I put all that into a separate test, ran it... and it works. The breakpoints are being hit, the DB context is being resolved, the Migrate() call works. So... that's weird. Then perhaps the issue is that some service descriptors already exist in the service collection which causes it to not create it through the configuration.

djmurp•2y ago

could you put a breakpoint in the constructor of your context, then look at stacktrace to see where it's being created?

ThinkerOP•2y ago

can try that

djmurp•2y ago

if it's not your lambda above then it must be somewhere else

ThinkerOP•2y ago

Okay so the constructor is being hit twice, which is expected. Once from Program.cs and once from my WebApplicationFactory. So I again suspect that there's some service I haven't properly cleared out which causes it to not run the configuration. okay I think I have an idea what the problem is

djmurp•2y ago

nice Is it because a servicedescriptor<MerpieContext> is added (the factory), but you were clearing out all MerpieContext even though there's none, so it's using the descriptor from Program.cs instead?

ThinkerOP•2y ago

Okay, the issue was that I was clearing MerpieContext but not DbContextOptions or DbContextOptions<MerpieContext>, so it didn't re-create those. works fine now catsleep

phaseshift•2y ago

Mark closed then rulesowo

ThinkerOP•2y ago

yes

Tvde1•2y ago

nice

Accord•2y ago

Looks like nothing has happened here. I will mark this as stale and this post will be archived until there is new activity.

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❔ ✅ AddSingleton and AddDbConnection are not running whatsoever