Upsert all in one db roundtrip

BulkUpsert.cs

public async Task<IActionResult> Upsert(BulkUpsertRequest request)
{
    request.Devices.ForEach(d =>
    {
        var device = new Device(d.Id, d.Name, d.Metadata.Select(...));
        _dbContext.Entry(device).IsModified = true;
    })

    await _dbContext.SaveAsync();
}