NopCommerce 多数据库方案

本文转自：http://www.cnblogs.com/YUTOUYUWEI/p/5538200.html

有时候一个项目需要连接多个数据库，以实现不同数据库的数据在同个项目的共享。

如果已经安装了nop，则需要在第二个数据库新建一个表，nop现在无法自动通过迁移来实现第二个或者更多数据库，所以这点需要我们手动去操作。

1、在SQLServer新建一个数据库，我这里新建的是TestDb，表为TestTable。

USE [TestDb]
GO

SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

CREATE TABLE [dbo].[TestTable](
       [Id] [int] IDENTITY(1,1) NOT NULL,
       [Name] [nvarchar](255) NOT NULL,
       [CreatedOnUtc] [datetime] NULL,
 CONSTRAINT [PK_TestTable] PRIMARY KEY CLUSTERED
(
       [Id] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
GO

2、添加实体，在Nop.Core下的Domain添加一个文件夹OtherDb，在OtherDb添加一个TestTable类，继承BaseEntity

TestTable：

namespace Nop.Core.Domain.OtherDb
{
    public class TestTable : BaseEntity
    {
        public string Name { get; set; }

        public DateTime CreatedOnUtc { get; set; }
    }
}

3、添加映射，在Nop.Data下的Mapping添加一个OtherDb文件夹，在OtherDb添加一个TestTableMap映射类，继承NopEntityTypeConfiguration< TestTable >

TestTableMap：

namespace Nop.Data.Mapping.OtherDb
{
    public class TestTableMap : NopEntityTypeConfiguration<TestTable>
    {
        public TestTableMap()
        {
            ToTable("TestTable");

            HasKey(t => t.Id);

            Property(t => t.Name).IsRequired().HasMaxLength(255);
        }
    }
}

4、添加新的DbContext，在Nop.Data添加一个OhterDb，里面添加一个OtherDbObjectContext类继承DbContext和IDbContext，添加一个OtherDbEfStartUpTask继承IStartTask

OtherDbObjectContext：

namespace Nop.Data.OtherDb
{
    public class OtherDbObjectContext : DbContext, IDbContext
    {
        public OtherDbObjectContext(string nameOrConnectionString)

            : base(nameOrConnectionString)
        {

        }

        protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {
            modelBuilder.Configurations.Add(new TestTableMap());
 
            base.OnModelCreating(modelBuilder);
        }

        public string CreateDatabaseScript()
        {
            return ((IObjectContextAdapter)this).ObjectContext.CreateDatabaseScript();
        }

        public new IDbSet<TEntity> Set<TEntity>() where TEntity : Core.BaseEntity
        {
            return base.Set<TEntity>();
        }

        public IList<TEntity> ExecuteStoredProcedureList<TEntity>(string commandText, params object[] parameters) where TEntity : Core.BaseEntity, new()
        {
            throw new NotImplementedException();
        }

        public IEnumerable<TElement> SqlQuery<TElement>(string sql, params object[] parameters)
        {
            throw new NotImplementedException();
        }

        public int ExecuteSqlCommand(string sql, bool doNotEnsureTransaction = false, int? timeout = null, params object[] parameters)
        {
            throw new NotImplementedException();
        }

        public void Detach(object entity)
        {
            throw new NotImplementedException();
        }

        public bool ProxyCreationEnabled
        {
            get { return this.Configuration.ProxyCreationEnabled; }

            set { this.Configuration.ProxyCreationEnabled = value; }
        }

        public bool AutoDetectChangesEnabled
        {
            get { return this.Configuration.AutoDetectChangesEnabled; }

            set { this.Configuration.AutoDetectChangesEnabled = value; }
        }
    }
}

OtherDbEfStartUpTask：

namespace Nop.Data.OtherDb
{
    public class OtherDbEfStartUpTask : IStartupTask
    {
        public void Execute()
        {
            Database.SetInitializer<OtherDbObjectContext>(null);
        }

        public int Order
        {
            get { return -1000; }
        }
    }
}

5、添加新的数据库连接字符串文本文件，用于连接TestDb数据库，在Nop.Web下面的App_Data下面添加一个文本文件命名OtherDbSetting.txt里面添加连接字符串

DataProvider: sqlserver

DataConnectionString: Data Source=.;Initial Catalog=TestDb;Integrated Security=False;Persist Security Info=False;User ID=登陆身份;Password=登陆密码

改变数据库连接名即可

6、在autofac注入新的OtherDbObjectContext，在Nop.WebFramework新建一个OtherDb文件夹，里面添加一个DependencyRegistrar类

DependencyRegistrar：

namespace Nop.Web.Framework.OtherDb
{
    public class DependencyRegistrar : IDependencyRegistrar
    {
        protected virtual string MapPath(string path)
        {
            if (HostingEnvironment.IsHosted)
            {
                return HostingEnvironment.MapPath(path);
            }
            else
            {
                string baseDirectory = AppDomain.CurrentDomain.BaseDirectory;

                path = path.Replace("~/", "").TrimStart('/').Replace('/', '\');

                return Path.Combine(baseDirectory, path);
            }
        }

        public void Register(ContainerBuilder builder, Core.Infrastructure.ITypeFinder typeFinder, Core.Configuration.NopConfig config)
        {
            var dataSettingManager = new DataSettingsManager();

            var dataProviderSettings = dataSettingManager.LoadSettings(Path.Combine(MapPath("~/App_Data/"), "OtherDbSetting.txt"));

            if (dataProviderSettings != null && dataProviderSettings.IsValid())
            {
                builder.Register<IDbContext>(c => new OtherDbObjectContext(dataProviderSettings.DataConnectionString))

                    .Named<IDbContext>("nop_object_context_otherdb").InstancePerLifetimeScope();

                //builder.Register<OtherDbObjectContext>(
                //    c => new OtherDbObjectContext(dataProviderSettings.DataConnectionString)).InstancePerLifetimeScope();
            }

            else
            {
                builder.Register<IDbContext>(

                    c => new OtherDbObjectContext(c.Resolve<DataSettings>().DataConnectionString)).InstancePerLifetimeScope();

                //builder.Register(

                //    c => new OtherDbObjectContext(c.Resolve<DataSettings>().DataConnectionString))

                //    .InstancePerLifetimeScope();

            }

            builder.RegisterType<EfRepository<TestTable>>()

                .As<IRepository<TestTable>>()

                .WithParameter(ResolvedParameter.ForNamed<IDbContext>("nop_object_context_otherdb"))

                .InstancePerLifetimeScope();
        }

        public int Order
        {
            get { return -1; }
        }
    }
}

全部添加没问题后，添加其他业务实现代码，重新生成解决方案即可。 此方案试用Nop3.4版本及以上，如有跟nop前期或者更新某个版本有差异，请自行斟酌修改。