I have a two dlls WebApp and MyUtils.EntityFramework they are both in the same directory and WebApp references MyUtils.EntityFramework.
This is how WebApp looks
public class Program
{
public static void Main()
{
var appServiceProivder = new ServiceCollection()
.AddDbContext<DerivedContext1>()
.BuildServiceProvider();
using (var serviceScope = appServiceProivder
.GetRequiredService<IServiceScopeFactory>()
.CreateScope())
{
var context = serviceScope.ServiceProvider.GetService<DerivedContext1>();
Debug.Assert(context.GetService<IDbContextOptions>()
.GetType() == typeof(DbContextOptions<DerivedContext1>));
}
}
}
[DbSchema("test")]
public class DerivedContext1 : DbContext
{
public DerivedContext1(DbContextOptions options) : base(options) { }
protected override void OnConfiguring(DbContextOptionsBuilder builder)
{
builder.UseSqlServer("secret connection string");
builder.ReplaceService<IHistoryRepository,
MigrationHistoryRepository<DerivedContext1>>();
}
}
this is how MyUtils.EntityFramework looks
public class DbSchemaAttribute : Attribute
{
public DbSchemaAttribute(string name)
{
Name = name;
}
public string Name { get; private set; }
}
public class MigrationHistoryRepository<TDbContext>
: SqlServerHistoryRepository where TDbContext : DbContext
{
public MigrationHistoryRepository(HistoryRepositoryDependencies dependencies)
: base(dependencies)
{
}
protected override string TableName { get { return "migration_history"; } }
protected override string TableSchema
{
get
{
var dsSchemaAttr = typeof(TDbContext)
.GetCustomAttributes(typeof(DbSchemaAttribute), true)
.SingleOrDefault() as DbSchemaAttribute;
if (dsSchemaAttr != null)
return dsSchemaAttr.Name;
return null;
}
}
protected override void ConfigureTable(EntityTypeBuilder<HistoryRow> history)
{
base.ConfigureTable(history);
history.HasKey(h => h.MigrationId).HasName($"{TableName}_pkey");
history.Property(h => h.MigrationId).HasColumnName("id");
history.Property(h => h.ProductVersion).HasColumnName("product_version");
}
}
and this is the error I get because of this line
builder.ReplaceService<IHistoryRepository, MigrationHistoryRepository<DerivedContext1>>();
bin output contains both dlls so I don't understand what the problem is (I'm using fedora 33)
An unhandled exception of type 'System.IO.FileNotFoundException' occurred in Microsoft.EntityFrameworkCore.dll: 'Could not load file or assembly 'MyUtils.EntityFramework, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null'. The system cannot find the file specified.'
at WebApp.DerivedContext1.OnConfiguring(DbContextOptionsBuilder builder) in /src/api/Program.cs:line 92
at Microsoft.EntityFrameworkCore.DbContext.get_InternalServiceProvider()
at Microsoft.EntityFrameworkCore.DbContext.Microsoft.EntityFrameworkCore.Infrastructure.IInfrastructure<System.IServiceProvider>.get_Instance()
at Microsoft.EntityFrameworkCore.Infrastructure.Internal.InfrastructureExtensions.GetService[TService](IInfrastructure`1 accessor)
at Microsoft.EntityFrameworkCore.Infrastructure.AccessorExtensions.GetService[TService](IInfrastructure`1 accessor)
at WebApp.Program.Main() in /src/api/Program.cs:line 78
It's because efcore utils is compiled multiple times, here is more detail How to organize multiple git packages in dotnet core
Related
I've been at it for days, but I can't get Unity to inject anything with RegisterType<> into my Controller. I'm using Web Api 2, in Visual Studio 2015, with Unity 4. Whenever I try to inject IUnitOfWork or IRFContext, I get "message": "An error occurred when trying to create a controller of type 'ClPlayersController'. Make sure that the controller has a parameterless public constructor.".
I'm using the Unity.AspNet.WebApi to bootstrapp into WebApi. Below is my UnityWebApiActivator
[assembly: WebActivatorEx.PreApplicationStartMethod(typeof(mycompany.project.api.UnityWebApiActivator), "Start")]
[assembly: WebActivatorEx.ApplicationShutdownMethod(typeof(mycompany.project.api.UnityWebApiActivator), "Shutdown")]
namespace mycompany.project.api
{
public static class UnityWebApiActivator
{
public static void Start()
{
var resolver = new UnityDependencyResolver(UnityConfig.GetConfiguredContainer());
GlobalConfiguration.Configuration.DependencyResolver = resolver;
}
public static void Shutdown()
{
var container = UnityConfig.GetConfiguredContainer();
container.Dispose();
}
}
}
I'm using a Start.cs due to Owin.
[assembly: OwinStartup(typeof(mycompany.project.api.Startup))]
namespace mycompany.project.api
{
public class Startup
{
public void Configuration(IAppBuilder app)
{
HttpConfiguration config = new HttpConfiguration();
ConfigureOAuth(app);
config.DependencyResolver = new UnityDependencyResolver(UnityConfig.GetConfiguredContainer());
WebApiConfig.Register(config);
app.UseCors(Microsoft.Owin.Cors.CorsOptions.AllowAll);
app.UseWebApi(config);
}
public void ConfigureOAuth(IAppBuilder app)
{
OAuthAuthorizationServerOptions OAuthServerOptions = new OAuthAuthorizationServerOptions()
{
AllowInsecureHttp = true,
TokenEndpointPath = new PathString("/token"),
AccessTokenExpireTimeSpan = TimeSpan.FromDays(1),
Provider = new SimpleAuthorizationServerProvider(),
RefreshTokenProvider = new SimpleRefreshTokenProvider()
};
// Token Generation
app.UseOAuthAuthorizationServer(OAuthServerOptions);
app.UseOAuthBearerAuthentication(new OAuthBearerAuthenticationOptions());
}
}
}
My WebApiConfig.cs is below:
namespace mycompany.project.api
{
public static class WebApiConfig
{
public static void Register(HttpConfiguration config)
{
log4net.Config.XmlConfigurator.Configure();
config.MapHttpAttributeRoutes();
config.EnableSystemDiagnosticsTracing();
config.Services.Add(typeof(IExceptionLogger),
new SimpleExceptionLogger(new LogManagerAdapter()));
config.Services.Replace(typeof(IExceptionHandler), new GlobalExceptionHandler());
}
}
}
My UnityConfig.cs is below
namespace mycompany.project.api
{
public class UnityConfig
{
#region Unity Container
private static Lazy<IUnityContainer> container = new Lazy<IUnityContainer>(() =>
{
var container = new UnityContainer();
RegisterTypes(container);
return container;
});
public static IUnityContainer GetConfiguredContainer()
{
return container.Value;
}
#endregion
public static void RegisterTypes(IUnityContainer container)
{
var config = new MapperConfiguration(cfg =>
{
//AutoMapper bindings
});
container.RegisterInstance<IMapper>(config.CreateMapper());
container.RegisterType<IRFContext, RFContext>(new PerThreadLifetimeManager());
container.RegisterType<IUnitOfWork, UnitOfWork>();
XmlConfigurator.Configure();
var logManager = new LogManagerAdapter();
container.RegisterInstance<ILogManager>(logManager);
}
}
}
All that I have in my Global.asax is below:
public class WebApiApplication : System.Web.HttpApplication
{
protected void Application_Error()
{
var exception = Server.GetLastError();
if (exception != null)
{
var log = new LogManagerAdapter().GetLog(typeof(WebApiApplication));
log.Error("Unhandled exception.", exception);
}
}
}
If my Controller is like this, it works fine:
public class ClPlayersController : ApiController
{
private readonly IMapper mapper;
public ClPlayersController(IMapper _mapper, IUnityContainer container)
{
mapper = _mapper;
}
But placing IUnitOfWork, like below, or the IRFContext, I get the error:
private readonly IMapper mapper;
private readonly IUnitOfWork unitOfWork;
public ClPlayersController(IMapper _mapper, IUnityContainer container, IUnitOfWork _unitOfWork)
{
mapper = _mapper;
unitOfWork = _unitOfWork;
}
I can't find, for the life of me, what I'm doing wrong. If I loop through the container.Registrations on the constructor, I find the mappings, but they refuse to get injected. Any hints?
EDIT
Below is the code for UnitOfWork and RFContext
namespace mycompany.project.data.configuracao
{
public class UnitOfWork : IUnitOfWork
{
private readonly IRFContext _rfContext;
private bool _disposed = false;
public UnitOfWork(IRFContext rfContext)
{
_rfContext = rfContext;
}
public void Commit()
{
if (_disposed)
{
throw new ObjectDisposedException(this.GetType().FullName);
}
_rfContext.SaveChanges();
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
protected virtual void Dispose(bool disposing)
{
if (_disposed) return;
if (disposing && _rfContext != null)
{
_rfContext.Dispose();
}
_disposed = true;
}
}
}
and
namespace mycompany.project.data.configuracao
{
public interface IUnitOfWork : IDisposable
{
void Commit();
}
}
and RFContext is a basic POCO generated DBContext
namespace mycompany.project.data.configuracao
{
using System.Linq;
public class RFContext : System.Data.Entity.DbContext, IRFContext
{
public System.Data.Entity.DbSet<ClGrupoEconomico> ClGrupoEconomicoes { get; set; }
//all my DbSets
public System.Data.Entity.DbSet<SpTipoLog> SpTipoLogs { get; set; }
static RFContext()
{
System.Data.Entity.Database.SetInitializer<RFContext>(null);
}
public RFContext()
: base("Name=RFContext")
{
}
public RFContext(string connectionString)
: base(connectionString)
{
}
public RFContext(string connectionString, System.Data.Entity.Infrastructure.DbCompiledModel model)
: base(connectionString, model)
{
}
public RFContext(System.Data.Common.DbConnection existingConnection, bool contextOwnsConnection)
: base(existingConnection, contextOwnsConnection)
{
}
public RFContext(System.Data.Common.DbConnection existingConnection, System.Data.Entity.Infrastructure.DbCompiledModel model, bool contextOwnsConnection)
: base(existingConnection, model, contextOwnsConnection)
{
}
protected override void Dispose(bool disposing)
{
base.Dispose(disposing);
}
protected override void OnModelCreating(System.Data.Entity.DbModelBuilder modelBuilder)
{
base.OnModelCreating(modelBuilder);
modelBuilder.Configurations.Add(new ClGrupoEconomicoConfiguration());
//all my Configuration classes
modelBuilder.Configurations.Add(new SpTipoLogConfiguration());
}
public static System.Data.Entity.DbModelBuilder CreateModel(System.Data.Entity.DbModelBuilder modelBuilder, string schema)
{
modelBuilder.Configurations.Add(new ClGrupoEconomicoConfiguration(schema));
//all my configuration classes
modelBuilder.Configurations.Add(new SpTipoLogConfiguration(schema));
return modelBuilder;
}
}
}
Unfortunately the exception you are seeing can occur for several reasons. One of them is when Unity cannot resolve one or more of your injections.
An error occurred when trying to create a controller of type
'FooController'. Make sure that the controller has a parameterless
public constructor.
So, based on the information in your question your setup is apparently correct, since IMapper can be injected. Therefore I guess that UnitOfWork and RFContext have dependencies that Unity cannot resolve. Maybe a repository?
UPDATE:
The problem here is that your RFContext has several constructors.
https://msdn.microsoft.com/en-us/library/cc440940.aspx#cnstrctinj_multiple
When a target class contains more than one constructor with the same
number of parameters, you must apply the InjectionConstructor
attribute to the constructor that the Unity container will use to
indicate which constructor the container should use. As with automatic
constructor injection, you can specify the constructor parameters as a
concrete type, or you can specify an interface or base class for which
the Unity container contains a registered mapping.
In this case Unity doesn't know how to resolve your RFContext, and will try to use the constructor with the most parameters. You can solve it by using
container.RegisterType<IRFContext, RFContext>(new InjectionConstructor());
My database have different schema depending on user selections on runtime.
My code is below:
public partial class FashionContext : DbContext
{
private string _schema;
public FashionContext(string schema) : base()
{
_schema = schema;
}
public virtual DbSet<Style> Styles { get; set; }
protected override void OnConfiguring(DbContextOptionsBuilder options)
{
options.UseSqlServer(#"Server=.\sqlexpress;Database=inforfashionplm;Trusted_Connection=True;");
}
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
modelBuilder.Entity<Style>()
.ToTable("Style", schema: _schema);
}
}
Upon testing. I created a context instance with 'schema1'.
So far so good.
But when I create another context instance with different schema 'schema2', the resulting data in which the schema is still on 'schema1'.
Here is the implementation:
using (var db = new FashionContext("schema1"))
{
foreach (var style in db.Styles)
{
Console.WriteLine(style.Name);
}
}
Console.ReadLine();
Console.Clear();
using (var db = new FashionContext("schema2"))
{
foreach (var style in db.Styles)
{
Console.WriteLine(style.Name);
}
}
Console.ReadLine();
Later I noticed that the OnModelCreating is called only one time, so it is never called again when you create a new context instance of the same connection string.
Is it possible to have dynamic schema on runtime? Note: this is possible in EF6
One of possible way was mentioned above, but briefly, so I will try to explain with examples.
You ought to override default ModelCacheKeyFactory and ModelCacheKey.
ModelCachekeyFactory.cs
internal sealed class CustomModelCacheKeyFactory<TContext> : ModelCacheKeyFactory
where TContext : TenantDbContext<TContext>
{
public override object Create(DbContext context)
{
return new CustomModelCacheKey<TContext>(context);
}
public CustomModelCacheKeyFactory([NotNull] ModelCacheKeyFactoryDependencies dependencies) : base(dependencies)
{
}
}
ModelCacheKey.cs, please review Equals and GetHashCode overridden methods, they are not best one and should be improved.
internal sealed class ModelCacheKey<TContext> : ModelCacheKey where TContext : TenantDbContext<TContext>
{
private readonly string _schema;
public ModelCacheKey(DbContext context) : base(context)
{
_schema = (context as TContext)?.Schema;
}
protected override bool Equals(ModelCacheKey other)
{
return base.Equals(other) && (other as ModelCacheKey<TContext>)?._schema == _schema;
}
public override int GetHashCode()
{
var hashCode = base.GetHashCode();
if (_schema != null)
{
hashCode ^= _schema.GetHashCode();
}
return hashCode;
}
}
Register in DI.
builder.UseSqlServer(dbConfiguration.Connection)
.ReplaceService<IModelCacheKeyFactory, CustomModelCacheKeyFactory<CustomContext>>();
Context sample.
public sealed class CustomContext : TenantDbContext<CustomContext>
{
public CustomContext(DbContextOptions<CustomContext> options, string schema) : base(options, schema)
{
}
}
You can build the model externally and pass it into the DbContext using DbContextOptionsBuilder.UseModel()
Another (more advanced) alternative is to replace the IModelCacheKeyFactory to take schema into account.
I found a way to recreate the compiled model on each context creation.
public partial class MyModel : DbContext {
private static DbConnection _connection
{
get
{
//return a new db connection
}
}
private static DbCompiledModel _model
{
get
{
return CreateModel("schema name");
}
}
public MyModel()
: base(_connection, _model, false)
{
}
private static DbCompiledModel CreateModel(string schema)
{
var modelBuilder = new DbModelBuilder();
modelBuilder.HasDefaultSchema(schema);
modelBuilder.Entity<entity1>().ToTable(schema + ".entity1");
var builtModel = modelBuilder.Build(_connection);
return builtModel.Compile();
}
}
I'm wondering how I can use Entity Framework's Code First Migrations without using NuGet at all (so no commands via the package manager console).
I tried the following:
Database-Context
public sealed class MyContext : DbContext
{
private const string ConnectionStringName = "MyDatabase";
public MyContext()
: base(ConnectionStringName)
{}
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
SetupMyModel(modelBuilder);
}
}
Migration-Configuration
public class MyMigrationConfiguration : DbMigrationsConfiguration<MyContext>
{
public MyMigrationConfiguration()
{
AutomaticMigrationsEnabled = false;
}
}
Database-Initializer
System.Data.Entity.Database.SetInitializer(new MigrateDatabaseToLatestVersion<MyContext, MyMigrationConfiguration>());
InitialDatabaseCreation Migration
public class InitialDatabaseCreation : DbMigration, IMigrationMetadata
{
public override void Up()
{
CreateTable("dbo.MyModel",
c => new
{
Id = c.Guid(false, true),
SomeProperty = c.Int(false)
})
.PrimaryKey(x => x.Id);
}
public override void Down()
{
DropTable("dbo.MyModel");
}
public string Id
{
get { return "0001_InitialDatabaseCreation"; }
}
public string Source
{
get { return null; }
}
public string Target
{
get { return Id; }
}
}
As you can see, I wrote a context, a migration configuration and the migration itself.
For the Migration, I'm not sure, if I implemented the IMigrationMetadata correcly. For the Target I just use the id, because I don't want to have any automatic migrations or the ability to use the package manager console. I think, this should be fine here?
I set a breakpoint at the Up method and debugged it, but it does not stop there, which means it doesn't get executed.
Therefor I want to know how to use the EF Code First migrations when writing everything manually.
We are using Caliburn Micro for the first time.
We have a AppBootstrapper inherited from ShellViewModel.
Situvation is that VieModels should have the same instance unless it is reset.
we are able to achieve shared or not shared everytime, but releasing the export whenever needed is still a mystery.
public class AppBootstrapper : Bootstrapper<ShellViewModel>
{
private static CompositionContainer _container;
protected override void Configure()
{
try
{
_container = new CompositionContainer(
new AggregateCatalog(AssemblySource.Instance.Select(x => new AssemblyCatalog(x))));
var batch = new CompositionBatch();
batch.AddExportedValue<IWindowManager>(new WindowManager());
batch.AddExportedValue<IEventAggregator>(new EventAggregator());
batch.AddExportedValue(_container);
StyleManager.ApplicationTheme = ThemeManager.FromName("Summer");
_container.Compose(batch);
}
catch (Exception exception)
{
}
}
public static void ReleaseAll()
{
}
protected override object GetInstance(Type serviceType, string key)
{
try
{
var contract = string.IsNullOrEmpty(key) ? AttributedModelServices.GetContractName(serviceType) : key;
var exports = _container.GetExportedValues<object>(contract);
if (exports.Any())
return exports.First();
throw new Exception(string.Format("Could not locate any instances of contract {0}.", contract));
}
catch (ReflectionTypeLoadException ex)
{
foreach (Exception inner in ex.LoaderExceptions)
{
// write details of "inner", in particular inner.Message
}
return null;
}
}
protected override IEnumerable<object> GetAllInstances(Type serviceType)
{
try
{
return _container.GetExportedValues<object>(AttributedModelServices.GetContractName(serviceType));
}
catch (Exception exception)
{
return null;
}
}
protected override void BuildUp(object instance)
{
_container.SatisfyImportsOnce(instance);
}
}
ShellViewModel
[Export(typeof(ShellViewModel))]
public sealed class ShellViewModel : Conductor<IScreen>.Collection.OneActive, IHandle<object>
{
[ImportingConstructor]
public ShellViewModel(CompositionContainer compositionContainer, IEventAggregator eventAggregator)
{
CompositionContainer = compositionContainer;
EventAggregator = eventAggregator;
eventAggregator.Subscribe(this);
Items.Add(compositionContainer.GetExportedValue<AViewModel>());
Items.Add(compositionContainer.GetExportedValue<BViewModel>());
ActivateItem(Items.Single(p => p.DisplayName == AppMessageType.A.ToString()));
}
public IEventAggregator EventAggregator { get; set; }
public CompositionContainer CompositionContainer { get; set; }
public void Handle(object message)
{
//throw new System.NotImplementedException();
}
public void B()
{
ActivateItem(Items.Single(p => p.DisplayName == AppMessageType.B.ToString()));
}
public void A()
{
ActivateItem(Items.Single(p => p.DisplayName == AppMessageType.A.ToString()));
}
public void RESET()
{
AppBootstrapper.ReleaseAll();
ActivateItem(Items.Single(p => p.DisplayName == AppMessageType.A.ToString()));
}
public enum AppMessageType
{
A,
B
}
}
AViewModel
[Export(typeof(AViewModel))]
public sealed class AViewModel : Conductor<IScreen>.Collection.OneActive, IHandle<object>
{
[ImportingConstructor]
public AViewModel(CompositionContainer compositionContainer, IEventAggregator eventAggregator)
{
DisplayName = ShellViewModel.AppMessageType.A.ToString();
CompositionContainer = compositionContainer;
EventAggregator = eventAggregator;
eventAggregator.Subscribe(this);
}
public IEventAggregator EventAggregator { get; set; }
public CompositionContainer CompositionContainer { get; set; }
public void Handle(object message)
{
//throw new System.NotImplementedException();
}
}
BViewModel
[Export(typeof(BViewModel))]
public sealed class BViewModel : Conductor<IScreen>.Collection.OneActive, IHandle<object>
{
[ImportingConstructor]
public BViewModel(CompositionContainer compositionContainer, IEventAggregator eventAggregator)
{
DisplayName = ShellViewModel.AppMessageType.B.ToString();
CompositionContainer = compositionContainer;
EventAggregator = eventAggregator;
eventAggregator.Subscribe(this);
}
public IEventAggregator EventAggregator { get; set; }
public CompositionContainer CompositionContainer { get; set; }
public void Handle(object message)
{
//throw new System.NotImplementedException();
}
}
Now AViewModel and BViewModel have single instance.
Whenever Release Button is clicked i want to have new instance of AViewModel and BViewModel.
Hoping to get a reply soon.
Regards,
Vivek
When working with an IoC container, the only part of your code that should take it as a dependency should be your composition root (i.e. your AppBootstrapper in this case). You shouldn't be injecting or referencing the container anywhere else in your code (except possibly factories).
If you want your ShellViewModel to control the lifetime of your child view models (A and B), then you should consider injecting view model factories into your ShellViewModel (via constructor injection if they are required dependencies).
Your AViewModelFactory would just have a single Create method that returns a new instance of AViewModel, likewise with the BViewModelFactory. You can simply new up your view models directly in the factories. If your view models have large dependency chains themselves, then you could consider adding a reference to your container in the factories, although preferably consider looking into the MEF ExportFactory<T> type.
Have been implementing Generic Repository, Unit of Work pattern with EF5 Code First from a number of resources and have come up with the following assemblies.
Interfaces, Contexts, Model, Repositories, UnitsOfWork
In the Context assembly I have my migrations folder which contains Configuration.cs
internal sealed class Configuration : DbMigrationsConfiguration<Context.SportsContext>
{
public Configuration()
{
AutomaticMigrationsEnabled = true;
}
protected override void Seed(Context.SportsContext context)
{
// This method will be called after migrating to the latest version.
// You can use the DbSet<T>.AddOrUpdate() helper extension method
// to avoid creating duplicate seed data. E.g.
//
// context.People.AddOrUpdate(
// p => p.FullName,
// new Person { FullName = "Andrew Peters" },
// new Person { FullName = "Brice Lambson" },
// new Person { FullName = "Rowan Miller" }
// );
//
}
}
As you can see this DbMigrationsConfiguration takes in my SportsContext which is also defined in the contexts assembly (Contexts folder)
public class SportsContext : IDbContext
{
private readonly DbContext _context;
public SportsContext()
{
_context = new DbContext("SportsContext");
}
public void Dispose()
{
_context.Dispose();
}
public IDbSet<T> GetEntitySet<T>() where T : class
{
return _context.Set<T>();
}
public void ChangeState<T>(T entity, EntityState state) where T : class
{
_context.Entry(entity).State = state;
}
public void SaveChanges()
{
_context.SaveChanges();
}
}
This implements IDbContext which is defined in the Interfaces assembly
public interface IDbContext : IDisposable
{
IDbSet<T> GetEntitySet<T>() where T : class;
void ChangeState<T>(T entity, EntityState state) where T : class;
void SaveChanges();
}
In my UnitsOfWork assembly I have the following class
public class SportUnitOfWork : IUnitofWork
{
private readonly IDbContext _context;
public SportUnitOfWork()
{
_context = new SportsContext();
}
private GenericRepository<Team> _teamRepository;
private GenericRepository<Fixture> _fixtureRepository;
public GenericRepository<Team> TeamRepository
{
get { return _teamRepository ?? (_teamRepository = new GenericRepository<Team>(_context)); }
}
public GenericRepository<Fixture> FixtureRepository
{
get { return _fixtureRepository ?? (_fixtureRepository = new GenericRepository<Fixture>(_context)); }
}
public void Save()
{
_context.SaveChanges();
}
public IDbContext Context
{
get { return _context; }
}
private bool _disposed;
protected virtual void Dispose(bool disposing)
{
if (!_disposed)
{
if (disposing)
{
_context.Dispose();
}
}
_disposed = true;
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
}
For examples sake I have added the GenericRepository class in the Repositories assembly
public class GenericRepository<T> : IGenericRepository<T> where T : class
{
private IDbContext _context;
public GenericRepository(IDbContext context)
{
_context = context;
}
public GenericRepository(IUnitofWork uow)
{
_context = uow.Context;
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
protected virtual void Dispose(bool disposing)
{
if (!disposing) return;
if (_context == null) return;
_context.Dispose();
_context = null;
}
public void Add(T entity)
{
_context.GetEntitySet<T>().Add(entity);
}
public void Update(T entity)
{
_context.ChangeState(entity, EntityState.Modified);
}
public void Remove(T entity)
{
_context.ChangeState(entity, EntityState.Deleted);
}
public T FindSingle(Expression<Func<T, bool>> predicate = null, params Expression<Func<T, object>>[] includes)
{
var set = FindIncluding(includes);
return (predicate == null) ? set.FirstOrDefault() : set.FirstOrDefault(predicate);
}
public IQueryable<T> Find(Expression<Func<T, bool>> predicate = null, params Expression<Func<T, object>>[] includes)
{
var set = FindIncluding(includes);
return (predicate == null) ? set : set.Where(predicate);
}
public IQueryable<T> FindIncluding(params Expression<Func<T, object>>[] includeProperties)
{
var set = _context.GetEntitySet<T>();
if (includeProperties != null)
{
foreach (var include in includeProperties)
{
set.Include(include);
}
}
return set.AsQueryable();
}
public int Count(Expression<Func<T, bool>> predicate = null)
{
var set = _context.GetEntitySet<T>();
return (predicate == null) ? set.Count() : set.Count(predicate);
}
public bool Exist(Expression<Func<T, bool>> predicate = null)
{
var set = _context.GetEntitySet<T>();
return (predicate == null) ? set.Any() : set.Any(predicate);
}
}
The problem I have is in the Configuration class which inherits from DbMigrationsConfiguration is expecting a DbContext parameter.
Error is Error 1 The type 'Contexts.Context.SportsContext' cannot be used as type parameter 'TContext' in the generic type or method 'System.Data.Entity.Migrations.DbMigrationsConfiguration'. There is no implicit reference conversion from 'Contexts.Context.SportsContext' to 'System.Data.Entity.DbContext'.
I can change the SportsContext to also inherit from DbContext but then I need to add a reference to EntityFramework 5 in the UnitsOfWork assembly as we want to possibly change or take out each layer without any reference to underlying models which is why i went with this pattern.
As we are looking at adding further contexts and models in the future so wanted to setup a architecture in that we could just add the context, model and then implement the relevant interfaces as and when needed.
A WebAPI Restful Web Service will be interacting with our data via the SportUnitOfWork, if I have understood the patterns correctly.
If anyone has any ideas on how I could do this or anything that I am doing wrong please let me know
thanks in advance Mark
Resolved this by doing the following
Changed my SportsContext class to a BaseContext which is abstract
public abstract class BaseContext : IDbContext
{
protected DbContext Context;
public void Dispose()
{
Context.Dispose();
}
public IDbSet<T> GetEntitySet<T>() where T : class
{
return Context.Set<T>();
}
public void Add<T>(T entity) where T : class
{
DbEntityEntry dbEntityEntry = GetDbEntityEntrySafely(entity);
dbEntityEntry.State = EntityState.Added;
}
public void Update<T>(T entity) where T : class
{
DbEntityEntry dbEntityEntry = GetDbEntityEntrySafely(entity);
dbEntityEntry.State = EntityState.Modified;
}
public void Delete<T>(T entity) where T : class
{
DbEntityEntry dbEntityEntry = GetDbEntityEntrySafely(entity);
dbEntityEntry.State = EntityState.Deleted;
}
public void SaveChanges()
{
// At the moment we are conforming to server wins when handling concurrency issues
// http://msdn.microsoft.com/en-us/data/jj592904
try
{
Context.SaveChanges();
}
catch (DbUpdateConcurrencyException e)
{
//Refresh using ServerWins
var objcontext = ((IObjectContextAdapter) Context).ObjectContext;
var entry = e.Entries;
objcontext.Refresh(RefreshMode.StoreWins, entry);
SaveChanges();
}
}
private DbEntityEntry GetDbEntityEntrySafely<T>(T entity) where T : class
{
DbEntityEntry dbEntityEntry = Context.Entry(entity);
if (dbEntityEntry.State == EntityState.Detached)
{
// Set Entity Key
var objcontext = ((IObjectContextAdapter) Context).ObjectContext;
if (objcontext.TryGetObjectByKey(dbEntityEntry.Entity))
Context.Set<T>().Attach(entity);
}
return dbEntityEntry;
}
}
created in the Context folder a new class called FootballContext which inherits from BaseContext.
public class FootballContext : BaseContext
{
public FootballContext(string connectionstringName)
{
Context = new BaseFootballContext(connectionstringName);
}
}
Created a new folder called DbContexts
In here created the following classes,
public class BaseFootballContext : DbContext
{
public BaseFootballContext(string nameOrConnectionString) : base(nameOrConnectionString)
{
}
public IDbSet<Fixture> Fixtures { get; set; }
public IDbSet<Team> Teams { get; set; }
}
public class MigrationsContextFactory : IDbContextFactory<BaseFootballContext>
{
public BaseFootballContext Create()
{
return new BaseFootballContext("FootballContext");
}
}
now my Configuration class can take in the BaseFootballContext as this is a DbContext.
My UnitOfWork class can now set the context to be FootballContext so does not have to reference EntityFramework.
This works with Migrations as well.
Only problem I have now is to figure out how to get this to work in a disconnected environment as I am having a problem reattaching entities and applying updates.