ASP - Core Migrate EF Core SQL DB on Startup

Question

Is it possible to have my ASP Core Web API ensure the DB is migrated to the latest migration using EF Core? I know this can be done through the command line, but I want to

Answer 1

Use below code to run migration at

public async void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
{
    using (var serviceScope = app.ApplicationServices.GetRequiredService<IServiceScopeFactory>().CreateScope())
    {
        var context = serviceScope.ServiceProvider.GetService<YourContext`enter code here`>();
        context.Database.Migrate();
    }
}

Answer 2

You can use

db.Database.EnsureCreated();

to get your db up to date with your current model. If you want to enable migrations (If subsequent migrations are suspected), then use

db.Database.Migrate();

and put your subsequent migrations over time.

Answer 3

Based on chintan310's answer, here is how I migrate the database. This ensures separation of database-related tasks into Program.cs:

    public static void Main(string[] args)
    {
        var host = BuildWebHost(args);

        using (var scope = host.Services.CreateScope())
        {
            var services = scope.ServiceProvider;

            try
            {
                var context = services.GetService<AppDbContext>();
                context.Database.Migrate();

                var seeder = scope.ServiceProvider.GetService<AppSeeder>();
                seeder.Seed().Wait();
            }
            catch (Exception ex)
            {
                var logger = services.GetRequiredService<ILogger<Program>>();
                logger.LogError(ex, "An error occurred seeding the DB.");
            }
        }

        host.Run();
    }

    private static IWebHost BuildWebHost(string[] args) =>
        WebHost.CreateDefaultBuilder(args)
            .UseStartup<Startup>()
            .Build();

Answer 4

This code works in .NET core 3.0

 using (var scope = app.ApplicationServices.CreateScope())
 {
     var dbContext = scope.ServiceProvider.GetService<T>();
     dbContext.Database.Migrate();
 }

Answer 5

Based on the answer of @steamrolla I would propose the following improvement:

public static class EnsureMigration
{
    public static void EnsureMigrationOfContext<T>(this IApplicationBuilder app) where T:DbContext
    {
        var context = app.ApplicationServices.GetService<T>();
        context.Database.Migrate();
    }
}

With this you can also ensure the migration of different contexts, e.g. if you have a Identity database.

Usage:

app.EnsureMigrationOfContext<context>();

Answer 6

I did this to migrate programmatically with EF Core 2.1.2 & SQL Server, based on previous answers here and bailando bailando's answer on "How and where to call Database.EnsureCreated and Database.Migrate?":

Startup.cs

using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.EntityFrameworkCore;

namespace MyApp
{
    public class Startup
    {
        // ... (only relevant code included) ...

        public void ConfigureServices(IServiceCollection services)
        {
            services.AddDbContext<MyAppContext>(options => 
                options.UseSqlServer(Configuration.GetConnectionString("MyAppContext")));
            // ...
        }

        public void Configure(IApplicationBuilder app, IHostingEnvironment env)
        {
            using (var serviceScope = app.ApplicationServices.CreateScope())
            {
                var context = serviceScope.ServiceProvider.GetService<MyAppContext>();
                context.Database.Migrate();
            }
            // ...
        }
    }
}

The project using this code is available at Github.