Applying Runtime Migrations . Net Core

Question

The question is exactly as in the title of this topic, but all the help I found related to the subject is running the code on the application startup requiring arguments to be passed to the host.

I would like to run the Migrations in a method of my controller after the user login in the system because I have a Multi Tenant scheme where I work with several banks and direct the user to your bank after the login changing the Connection String in memory.

References:

https://stackoverflow.com/questions/41090881/migrating-at-runtime-with-entity-framework-core https://docs.microsoft.com/en-us/ef/core/managing-schemas/migrations/applying?tabs=dotnet-core-cli

Code found to place on startup:

public void ConfigureServices(IServiceCollection services)
{
    // Wire up whatever your equivalent DbContext class is here
    services.AddDbContext<ApplicationDbContext>();
}

public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
{
    using (var scope = app.ApplicationServices.GetRequiredService<IServiceScopeFactory>().CreateScope())
    {
        scope.ServiceProvider.GetService<ApplicationDbContext>().Database.Migrate();
    }
}

My Login Method:

 public IActionResult Login(LoginViewModel loginVm)
{
            Constants.ConnectionString = config.GetConnectionString("ConnString_Generica").Replace("[CLIENTE]", loginVm.Cnpj);

            try
            {
                using (var connection = new SqlConnection(Constants.ConnectionString))
                {
                    connection.Open();
                }
            }
            catch (Exception)
            {
                loginVm.MessageValidation = Resources.Resources.TentativaInvalida;
                return View(loginVm);
            }
            
            ///Após isso aplicar os migrations
}

Answer 1

If you are already doing the injection of ApplicationDbContext in the dependencies injection container by means of the services.AddDbContext<ApplicationDbContext>() inside ConfigureServices, you can get it from the controller builder:

public class LoginController : ControllerBase
{
    private readonly ApplicationDbContext _dbContext;

    public LoginController(
        ApplicationDbContext applicationDbContext)
    {
        _dbContext = applicationDbContext;
    }

    public IActionResult Login(LoginViewModel loginVm)
    {
        Constants.ConnectionString = config.GetConnectionString("ConnString_Generica").Replace("[CLIENTE]", loginVm.Cnpj);

        try
        {
            using (var connection = new SqlConnection(Constants.ConnectionString))
            {
                connection.Open();
            }
        }
        catch (Exception)
        {
            loginVm.MessageValidation = Resources.Resources.TentativaInvalida;
            return View(loginVm);
        }

        _dbContext.Database.Migrate();
    }
}

as shown above, you could apply Migration inside the controller: _dbContext.Database.Migrate()