Set provider name manually in DbContext constructor - entity-framework

I need to store the connection string somewhere else other than web.config. Currency I am using a .json file to store it and a static class to read from it.
Here is my data context -
public partial class MyDatabaseContext : DbContext
{
public MyDatabaseContext() : base()
{
Database.Connection.ConnectionString = GlobalConfig.ConnectionString;
}
}
This is GlobalConfig class
public static class GlobalConfig
{
public static string ConnectionString
{
get
{
return "Server=MyServer; Database=MyDb; Integrated Security=SSPI;";
}
}
}
I need to assign provider name System.Data.SqlClient to the context. How can I do that here?

Its possible to load DbConfiguration class at the DbContext Constructor
Define a class that implement DbConfiguration (Oracle in this case)
public class AppDbConfiguration : DbConfiguration
{
public AppDbConfiguration()
{
// use code based configuration
SetDefaultConnectionFactory(new OracleConnectionFactory());
SetProviderServices("Oracle.ManagedDataAccess.Client",EFOracleProviderServices.Instance);
SetProviderFactory("Oracle.ManagedDataAccess.Client", new OracleClientFactory());
}
}
Use it in your context
public AppDbContext(string connString) : base(connString)
{
DbConfiguration.SetConfiguration(new AppDbConfiguration());
}
Don't forget to install the currect Package for your provider (in this example its ODP.net from nuget package manager)

Related

Creating Repository Pattern that provides multiple DbContexts with Entity Framework in .Net Core Web API

I want to develop a structure that will support generic DbContexts in the .Net Core Web API project and can be used in the repository pattern. Mysql and PostreSql databases are sufficient for now. Can you help with this?
Create a new .Net Core Web API project.
Add a new folder in the project called DataAccess and create a new class called BaseDbContext that inherits from DbContext. This class will contain the common properties and methods for all your DbContexts.
public class BaseDbContext : DbContext
{
public BaseDbContext(DbContextOptions options) : base(options) { }
//...
}
Create a new class called MySqlDbContext that inherits from BaseDbContext. This class will contain the properties and methods specific to the MySQL database.
public class MySqlDbContext : BaseDbContext
{
public MySqlDbContext(DbContextOptions<MySqlDbContext> options) : base(options) { }
//...
}
Create a new class called PostgreSqlDbContext that inherits from BaseDbContext. This class will contain the properties and methods specific to the PostgreSQL database.
public class PostgreSqlDbContext : BaseDbContext
{
public PostgreSqlDbContext(DbContextOptions<PostgreSqlDbContext> options) :
base(options) { }
//...
}
Create a new folder in the project called Repositories and create a new class called BaseRepository that will contain the common methods for all your repositories.
public class BaseRepository<T> where T : class
{
protected readonly DbContext _context;
public BaseRepository(DbContext context)
{
_context = context;
}
//...
}
Create new classes for each repository that inherits from BaseRepository and pass the appropriate DbContext to the base constructor.
public class MySqlRepository : BaseRepository<MySqlDbContext>
{
public MySqlRepository(MySqlDbContext context) : base(context) { }
//...
}
and
public class PostgreSqlRepository : BaseRepository<PostgreSqlDbContext>
{
public PostgreSqlRepository(PostgreSqlDbContext context) : base(context) { }
//...
}
In your controllers you can now inject the appropriate repository and use it to interact with the database.
You can also use dependency injection to inject the appropriate DbContext based on the configuration.
Additional:
Here is an example of how you can do this:
In your appsettings.json file, add a section for the database connection information, such as:
{
"ConnectionStrings": {
"MySqlConnection": "Server=localhost;Database=mydb;User=user;Password=password;",
"PostgreSqlConnection": "Host=localhost;Database=mydb;Username=user;Password=password;"
},
"DatabaseProvider": "MySql"
}
Here the DatabaseProvider field indicate the database that user wants to use.
2. In your Startup.cs file, create a new method called ConfigureDbContext that will configure the DbContext based on the configuration in the appsettings file
public void ConfigureDbContext(IServiceCollection services)
{
var connectionString = Configuration.GetConnectionString("MySqlConnection");
var provider = Configuration.GetValue<string>("DatabaseProvider");
if(provider == "MySql")
{
services.AddDbContext<MySqlDbContext>(options => options.UseMySql(connectionString));
}
else if (provider == "PostgreSql")
{
services.AddDbContext<PostgreSqlDbContext>(options => options.UseNpgsql(connectionString));
}
}
In the ConfigureServices method in Startup.cs, call the ConfigureDbContext method to configure the DbContext.
public void ConfigureServices(IServiceCollection services)
{
ConfigureDbContext(services);
//...
}
In your controllers, you can now inject the appropriate DbContext using dependency injection.
public class MyController : Controller
{
private readonly IDbContext _context;
public MyController(IDbContext context)
{
_context = context;
}
//...
}

Multiple registration configuration based on string info Autofac

Finally I found the answer, thanks #yeah-buddy
Autofac Resolve constructor instance from Container?
public class Car
{
public Car(IEngine engine) { }
}
public interface IEngine { }
public interface IRepository { }
public class Engine : IEngine
{
public Engine(IRepository repository) { }
}
public class GenericRepository : IRepository
{
public GenericRepository(string carName) { } // !!! Generic Repository write information to carName table, this dependency is keypoint)
}
I want to register:
"Ferrari": Use Engine with GenericRepository("Ferrari")
"Volvo": Use Engine with GenericRepository("Volvo")
I want to resolve:
Get "Ferrari" Car
Get "Ferrari" Repository
How can I achieve this requirement by Autofac?

How to Register a conventional Interface in Autofac

I have an autofac DI in my project.
I want to expose an interface by conventional which all other interfaces of my project will inherit from. Is it possible to automatically register the components of the inherited interfaces at start up level? For example:
Public interface IConvetionInterface {}
public interface IImplementationA:IConvetionInterface
{
public void DoSomethingA();
}
public interface IImplementationB:IConvetionInterface
{
public void DoSomethingB();
}
Injecting through constructor;
public class ConsumerA
{
private readonly IImplementationA _a;
public DealerRepository(IImplementationA A)
{
_a= A;
}
public Act()
{
_a.DoSomethingA();
}
}
How do I register IConvetionInterface to make all its dependencies resolve in Autofac.
I have been able to come up with this solution by using autofac Assembly Scanning Configuration as provided in their documentation page Autofac Documentation Page
I have an open generic interface
public interface IRepository<TEntity, TPrimaryKey> where TEntity : class, IEntity<TPrimaryKey>
{ }
Implemented by
public class Repository<TEntity, TPrimaryKey> : RepositoryBase<TEntity, TPrimaryKey>
where TEntity : class, IEntity<TPrimaryKey>{}
Then, I created an empty interface
public interface IConventionDependency
{
}
This method was called to register my components at startup level:
public static void RegisterAPSComponents(ContainerBuilder builder)
{
builder.RegisterType<APSContext>().InstancePerRequest();
builder.RegisterGeneric(typeof(Repository<,>)).As(typeof(IRepository<,>)).InstancePerLifetimeScope();
builder.RegisterAssemblyTypes(typeof(IConventionDependency).Assembly).AssignableTo<IConventionDependency>().As<IConventionDependency>().AsImplementedInterfaces().AsSelf().InstancePerLifetimeScope();
}
By the above registration, any interface that inherits from IConventionDependency will be registered automatically in the container.
example:
create an interface:
public interface IDealerRepository : IConventionDependency
{
List<Dealers> GetDealers();
}
then Implement the interface :
public class DealerRepository : IDealerRepository
{
private readonly IRepository<VTBDealer, int> _repository;
public DealerRepository(IRepository<VTBDealer, int> repository)
{
_repository = repository;
}
public List<Dealers> GetDealers()
{
return _repository.GetAllList().MapTo<List<Dealers>>();
}
}
in conclusion, without explicitly registering IDealerRepository, it gets resolved in MVC Controller constructor.

creating NHibernate repositories in view models with IoC

I would like to how to correct build and handle with NHibernate repository and session in view models classes.
For example I use Caliburn Micro framework with Castle Windsor boostraper.
First I created NHibernate repository:
public interface IRepository{//I omitted not needed code for simplification}
public class NHibRepository: IRepository
{
private ISession _session;
public NHibRepository(ISession session)
{
_session=session;
}
// I omitted not needed code for simplification
}
Second I definied some POCO class and mapping class with Fluent NHibernate.
public class User{}
public class Profile{}
public class Album{}
public class UserMap : ClassMap<User>{}
public class ProfileMap : ClassMap<Profile>{}
public class AlbumMap : ClassMap<Album>{}
Now I need use NHibernate repositories in my view models.
public interface IViewModelA{}
public class ViewModelA : ScreenViewModel, IViewModelA
{
public NHibRepository<User> UserRepo{get;set;}
public NHibRepository<Profile> ProfileRepo{get;set;}
}
public interface IViewModelB{}
public class ViewModelB : Screen, IViewModelB
{
public NHibRepository<Profile> ProfileRepo{get;set;}
public NHibRepoistory<Album> AlbumRepo{get;set;}
}
When I am creating repository class for some entity class I need pass session to NHibRepository construtor.
UserRepo= new NHibRepository<User>(NHIBERNATE SESSION);
Until now I used some helper class for creating Nhibernate session and init repository.
Helper class is here:
public class FluentNHibHelper
{
private ISessionFactory _sessionFactory;
public FluentNHibHelper(IPersistenceConfigurer db, Assembly asm)
{
InitializeSessionFactory(db, asm);
}
private void InitializeSessionFactory(IPersistenceConfigurer db, Assembly asm)
{
_sessionFactory = Fluently.Configure()
.Database(db)
.Mappings(m => m.FluentMappings.AddFromAssembly(asm))
.ExposeConfiguration(cfg => new SchemaUpdate(cfg).Execute(true, true))
.BuildSessionFactory();
}
public ISession OpenSession()
{
return _sessionFactory.OpenSession();
}
}
with this class I created repository class:
private const string ConnString =
#"Server=TestMachine\SQLEXPRESS;Database=TEST;Trusted_Connection=True;";
UserRepo = new NHibRepository<User>(
new FluentNHibHelper(MsSqlConfiguration.MsSql2008.ConnectionString(ConnString),
Assembly.GetExecutingAssembly())
.OpenSession());
Now I am confuse I don’t what is the best way for creating repository object in view models.
For example in bootstraper class can I somehow register repository class ?
public class CastleBootstrapper : Bootstrapper<IShellViewModel>
{
private IWindsorContainer _windsorContainer;
protected override void Configure()
{
_windsorContainer = new WindsorContainer();
//register repository class here ???
}
}
Can anybody help me? Thank you very much
Sorry for my english.
I use the following in an ASP.net MVC application. Castle.Windsor takes care of creating the ISession dependency for each repository.
//Located in your application startup
protected IWindsorContainer CreateContainer()
{
container = new WindsorContainer();
container.Install(
new PersistenceInstaller(),
new RepositoryInstaller()
//, other installers here
);
return container;
}
public class PersistenceInstaller : IWindsorInstaller
{
public void Install(IWindsorContainer container, IConfigurationStore store)
{
container.AddFacility<PersistenceFacility>();
}
}
public class PersistenceFacility : AbstractFacility
{
protected override void Init()
{
NHibernate.Cfg.Configuration config = BuildDatabaseConfiguration();
Kernel.Register(
Component.For<ISessionFactory>()
.UsingFactoryMethod(config.BuildSessionFactory),
Component.For<ISession>()
.UsingFactoryMethod(k => k.Resolve<ISessionFactory>().OpenSession())
.LifeStyle.Trasient
);
}
private NHibernate.Cfg.Configuration BuildDatabaseConfiguration()
{
return Fluently.Configure()
.Database(SetupDatabase)
.Mappings(m => m.HbmMappings.AddFromAssemblyOf<Entity>())
.ExposeConfiguration(ConfigurePersistence)
.BuildConfiguration();
}
protected virtual IPersistenceConfigurer SetupDatabase()
{
return MsSqlConfiguration.MsSql2008
.UseOuterJoin()
.ConnectionString(x => x.FromConnectionStringWithKey("ApplicationServices"))
.ShowSql();
}
protected virtual void ConfigurePersistence(NHibernate.Cfg.Configuration config)
{
SchemaMetadataUpdater.QuoteTableAndColumns(config);
}
protected virtual bool IsDomainEntity(Type t)
{
return typeof(DomainBase).IsAssignableFrom(t);
}
}
public class RepositoryInstaller : IWindsorInstaller
{
public void Install(IWindsorContainer container, IConfigurationStore store)
{
container.Register(Find().Configure(ConfigureLifeStyle()));
}
private ConfigureDelegate ConfigureLifeStyle()
{
return c => c.LifeStyle.Transient;
}
private BasedOnDescriptor Find()
{
return AllTypes.FromAssemblyContaining<NHRepository>()
.Where(type => type.Name.EndsWith("Repository"))
.WithService
.AllInterfaces();
}
}

Parameterless implementation for Ninject mappings

i am creating custom membership provider using ninject for binding to sql classes.
my class in looks like
public MyMembershipProvider(IUsersRepository userRepository)
{
this.userRepository = userRepository;
}
How can i create from this parameterless constructor?
kernel.Bind<IUsersRepository>().To<UsersRepository>();
kernel.Bind<MembershipProvider>().To<MyMembershipProvider>();
and then:
public class AccountController : Controller
{
private readonly MembershipProvider _membershipProvider;
public AccountController(MembershipProvider membershipProvider)
{
_membershipProvider = membershipProvider;
}
public ActionResult Foo()
{
// TODO: Use the membership provider to do some processing
return View();
}
}