实体框架代码优先-更新不同项目中的数据库

Question

I have a test dbcontext which I use for integration tests, which have pending changes. It's in this project: app.WebApi.Integration

using System.Data.Entity;
using System.Data.Entity.Infrastructure;
using app.Web.Data;
using app.Web.Model.Entities;

namespace app.WebApi.Integration.Data
{
    public class IntegrationTestDbContext : DbContext, IDbContextFactory<IntegrationTestDbContext>
    {
        public IntegrationTestDbContext(string conn = "DefaultConnection")
            : base(conn)
        {
            Configuration.LazyLoadingEnabled = false;
        }

        public IntegrationTestDbContext() { }

        public virtual IDbSet<Question> Questions { get; set; }
        public virtual IDbSet<Answer> Answers { get; set; }


        public virtual void MarkAs(object item, EntityState entityState)
        {
            Entry(item).State = entityState;
        }

        public IntegrationTestDbContext Create()
        {
            return new IntegrationTestDbContext();
        }
    }
}

But my migrations are in a seperate project: app.Web.Data. Does anyone know an ef command where I can update IntegrationTestDbContext with the migrations from the other project?

Answer 1

You need a custom DbMigrationsConfiguration :

namespace MyProgram.Migrations
{
    using System;
    using System.Data.Entity;
    using System.Data.Entity.Migrations;
    using System.Linq;
    using System.Reflection;
    using MyProgram;

    internal sealed class MyConfiguration : DbMigrationsConfiguration<MyProgram.MyDbContext>
    {
        public Configuration()
        {
            AutomaticMigrationsEnabled = false;

            // This is the assembly where your real migration are (Your DbContext not for test!)
            MigrationsAssembly = Assembly.GetExecutingAssembly();
            MigrationsNamespace = "AssemblyNamespace.Migrations";
        }
    }
}

After that you can create the migration from the code by using DbMigrator or use the NuGet console like that:

Update-Database [-SourceMigration ] [-TargetMigration ] [-Script] [-Force] [-ProjectName ] [-StartUpProjectName ] [-ConfigurationTypeName ] [-ConnectionStringName ] []

Update-Database will create and update the used database.

Update-Database -TargetMigration YourId -ProjectName MyProject -ConfigurationTypeName MyProject.Migrations.MyConfiguration

You can pass the connection string as parameter for the update-database command if the the startup project(app.config) does not contains the connection string

Answer 2

This is the command what I use for .net core (.net 5)

dnx ef migrations add ClassLibraryMigration -c ClassLibraryContext -p ClassLibrary

dnx ef database update -c ClassLibaryContext