NHibernate Composite Interceptor

CompositeInterceptor.cs

using System.Collections;
using System.Collections.Generic;
using System.Linq;
using MoreLinq;
using NHibernate;
using NHibernate.SqlCommand;
using NHibernate.Type;

public class CompositeInterceptor : IInterceptor
{
    private readonly IEnumerable<IInterceptor> _interceptors;

    public CompositeInterceptor(IEnumerable<IInterceptor> interceptors)
    {
        _interceptors = interceptors.ToList();
    }

    public void AfterTransactionBegin(ITransaction tx)
    {
        _interceptors.ForEach(x => x.AfterTransactionBegin(tx));
    }

    public void AfterTransactionCompletion(ITransaction tx)
    {
        _interceptors.ForEach(x => x.AfterTransactionCompletion(tx));
    }

    public void BeforeTransactionCompletion(ITransaction tx)
    {
        _interceptors.ForEach(x => x.BeforeTransactionCompletion(tx));
    }

    public int[] FindDirty(object entity, object id, object[] currentState, 
        object[] previousState, string[] propertyNames, IType[] types)
    {
        var results = _interceptors
            .Select(interceptor => interceptor.FindDirty(entity, id,
                currentState, previousState, propertyNames, types))
            .Where(result => result != null)
            .SelectMany(x => x)
            .Distinct()
            .ToArray();
        return !results.Any() ? null : results;
    }

    public object GetEntity(string entityName, object id)
    {
        return _interceptors
            .Select(interceptor => interceptor.GetEntity(entityName, id))
            .FirstOrDefault(result => result != null);
    }

    public string GetEntityName(object entity)
    {
        return _interceptors
            .Select(interceptor => interceptor.GetEntityName(entity))
            .FirstOrDefault(result => result != null);
    }

    public object Instantiate(string entityName, EntityMode entityMode, object id)
    {
        return _interceptors
            .Select(interceptor => interceptor.Instantiate(entityName, entityMode, id))
            .FirstOrDefault(result => result != null);
    }

    public bool? IsTransient(object entity)
    {
        return _interceptors
            .Select(interceptor => interceptor.IsTransient(entity))
            .FirstOrDefault(result => result != null);
    }

    public void OnCollectionRecreate(object collection, object key)
    {
        _interceptors.ForEach(x => x.OnCollectionRecreate(collection, key));
    }

    public void OnCollectionRemove(object collection, object key)
    {
        _interceptors.ForEach(x => x.OnCollectionRemove(collection, key));
    }

    public void OnCollectionUpdate(object collection, object key)
    {
        _interceptors.ForEach(x => x.OnCollectionUpdate(collection, key));
    }

    public void OnDelete(object entity, object id, object[] state, 
        string[] propertyNames, IType[] types)
    {
        _interceptors.ForEach(x => x.OnDelete(entity, id, state, propertyNames, types));
    }

    public bool OnFlushDirty(object entity, object id, object[] currentState, 
        object[] previousState, string[] propertyNames, IType[] types)
    {
        return _interceptors.Count(interceptor => interceptor.OnFlushDirty(
            entity, id, currentState, previousState, propertyNames, types)) > 0;
    }

    public bool OnLoad(object entity, object id, object[] state, 
        string[] propertyNames, IType[] types)
    {
        return _interceptors.Count(interceptor => interceptor.OnLoad(
            entity, id, state, propertyNames, types)) > 0;
    }

    public SqlString OnPrepareStatement(SqlString sql)
    {
        return _interceptors.Aggregate(sql, (current, interceptor) => 
            interceptor.OnPrepareStatement(current));
    }

    public bool OnSave(object entity, object id, object[] state, 
        string[] propertyNames, IType[] types)
    {
        return _interceptors.Count(interceptor => interceptor.OnSave(
            entity, id, state, propertyNames, types)) > 0;
    }

    public void PostFlush(ICollection entities)
    {
        _interceptors.ForEach(x => x.PostFlush(entities));
    }

    public void PreFlush(ICollection entities)
    {
        _interceptors.ForEach(x => x.PreFlush(entities));
    }

    public void SetSession(ISession session)
    {
        _interceptors.ForEach(x => x.SetSession(session));
    }
}

CompositeInterceptorTests.cs

using System.Collections;
using NHibernate;
using NHibernate.SqlCommand;
using NHibernate.Type;
using NSubstitute;
using NUnit.Framework;
using Sentric.BackOffice.Infrastructure.Data.Orm.NHibernate;
using Should;

[TestFixture]
public class CompositeInterceptorTests
{
    [Test]
    public void Should_call_after_transaction_begin()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();
        var transaction = Substitute.For<ITransaction>();

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.AfterTransactionBegin(transaction);

        interceptor1.Received().AfterTransactionBegin(transaction);
        interceptor2.Received().AfterTransactionBegin(transaction);
    }

    [Test]
    public void Should_call_after_transaction_completion()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();
        var transaction = Substitute.For<ITransaction>();

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.AfterTransactionCompletion(transaction);

        interceptor1.Received().AfterTransactionCompletion(transaction);
        interceptor2.Received().AfterTransactionCompletion(transaction);
    }

    [Test]
    public void Should_call_before_transaction_completion()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();
        var transaction = Substitute.For<ITransaction>();

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.BeforeTransactionCompletion(transaction);

        interceptor1.Received().BeforeTransactionCompletion(transaction);
        interceptor2.Received().BeforeTransactionCompletion(transaction);
    }

    [Test]
    public void Should_call_finddirty_on_all_interceptors()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();
        var interceptor3 = Substitute.For<IInterceptor>();

        var entity = new object();
        var id = new object();
        var currentState = new object[] { 0 };
        var previousState = new object[] { 0 };
        var propertyNames = new[] { "Id" };
        var types = new[] { Substitute.For<IType>() };

        interceptor1.FindDirty(entity, id, currentState, previousState, propertyNames, types).Returns(new [] { 1, 2 });
        interceptor2.FindDirty(entity, id, currentState, previousState, propertyNames, types).Returns(new[] { 2, 3 });
        interceptor3.FindDirty(entity, id, currentState, previousState, propertyNames, types).Returns((int[])null);

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.FindDirty(entity, id, currentState, previousState, propertyNames, types)
            .ShouldEqual(new [] { 1, 2, 3 });
    }

    [Test]
    public void Should_return_null_when_finddirty_returns_no_results()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();

        var entity = new object();
        var id = new object();
        var currentState = new object[] { 0 };
        var previousState = new object[] { 0 };
        var propertyNames = new[] { "Id" };
        var types = new[] { Substitute.For<IType>() };

        interceptor1.FindDirty(entity, id, currentState, previousState, propertyNames, types).Returns((int[])null);
        interceptor2.FindDirty(entity, id, currentState, previousState, propertyNames, types).Returns(new int[] { });

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });

        interceptor.FindDirty(entity, id, currentState, 
            previousState, propertyNames, types).ShouldBeNull();
    }
    
    [Test]
    public void Should_call_getentity_first_interceptor_valid()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();

        var entityName = string.Empty;
        var id = new object();

        interceptor1.GetEntity(entityName, id).Returns(new object());

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.GetEntity(entityName, id);

        interceptor1.Received().GetEntity(entityName, id);
        interceptor2.DidNotReceive().GetEntity(entityName, id);
    }

    [Test]
    public void Should_call_getentity_second_interceptor_valid()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();

        var entityName = string.Empty;
        var id = new object();

        interceptor2.GetEntity(entityName, id).Returns(new object());

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.GetEntity(entityName, id);

        interceptor1.Received().GetEntity(entityName, id);
        interceptor2.Received().GetEntity(entityName, id);
    }

    [Test]
    public void Should_call_get_entity_name_first_interceptor_valid()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();

        var entity = new object();

        interceptor1.GetEntityName(entity).Returns(string.Empty);

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.GetEntityName(entity);

        interceptor1.Received().GetEntityName(entity);
        interceptor2.DidNotReceive().GetEntityName(entity);
    }

    [Test]
    public void Should_call_get_entity_name_second_interceptor_valid()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();

        var entity = new object();

        interceptor1.GetEntityName(entity).Returns((string)null);
        interceptor2.GetEntityName(entity).Returns(string.Empty);

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.GetEntityName(entity);

        interceptor1.Received().GetEntityName(entity);
        interceptor2.Received().GetEntityName(entity);
    }

    [Test]
    public void Should_call_instantiate_first_interceptor_valid()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();

        var entityName = string.Empty;
        const EntityMode entityMode = EntityMode.Map;
        var id = new object();

        interceptor1.Instantiate(entityName, entityMode, id).Returns(new object());

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.Instantiate(entityName, entityMode, id);

        interceptor1.Received().Instantiate(entityName, entityMode, id);
        interceptor2.DidNotReceive().Instantiate(entityName, entityMode, id);
    }

    [Test]
    public void Should_call_instantiate_second_interceptor_valid()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();

        var entityName = string.Empty;
        const EntityMode entityMode = EntityMode.Map;
        var id = new object();

        interceptor2.Instantiate(entityName, entityMode, id).Returns(new object());

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.Instantiate(entityName, entityMode, id);

        interceptor1.Received().Instantiate(entityName, entityMode, id);
        interceptor2.Received().Instantiate(entityName, entityMode, id);
    }

    [Test]
    public void Should_call_istransient_first_interceptor_valid()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();

        var entity = new object();

        interceptor1.IsTransient(entity).Returns(true);

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.IsTransient(entity);

        interceptor1.Received().IsTransient(entity);
        interceptor2.DidNotReceive().IsTransient(entity);
    }

    [Test]
    public void Should_call_istransient_second_interceptor_valid()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();

        var entity = new object();

        interceptor2.IsTransient(entity).Returns(true);

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.IsTransient(entity);

        interceptor1.Received().IsTransient(entity);
        interceptor2.Received().IsTransient(entity);
    }

    [Test]
    public void Should_call_oncollectionrecreate()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();

        var collection = new object();
        var key = new object();

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.OnCollectionRecreate(collection, key);

        interceptor1.Received().OnCollectionRecreate(collection, key);
        interceptor2.Received().OnCollectionRecreate(collection, key);
    }

    [Test]
    public void Should_call_oncollectionremove()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();

        var collection = new object();
        var key = new object();

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.OnCollectionRemove(collection, key);

        interceptor1.Received().OnCollectionRemove(collection, key);
        interceptor2.Received().OnCollectionRemove(collection, key);
    }

    [Test]
    public void Should_call_oncollectionupdate()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();

        var collection = new object();
        var key = new object();

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.OnCollectionUpdate(collection, key);

        interceptor1.Received().OnCollectionUpdate(collection, key);
        interceptor2.Received().OnCollectionUpdate(collection, key);
    }

    [Test]
    public void Should_call_ondelete()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();

        var entity = new object();
        var id = new object();
        var state = new object[] { 0 };
        var propertyNames = new[] { "Id" };
        var types = new[] { Substitute.For<IType>() };

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.OnDelete(entity, id, state, propertyNames, types);

        interceptor1.Received().OnDelete(entity, id, state, propertyNames, types);
        interceptor2.Received().OnDelete(entity, id, state, propertyNames, types);
    }

    [Test]
    public void Should_call_onflushdirty_false()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();

        var entity = new object();
        var id = new object();
        var currentState = new object[] { 0 };
        var previousState = new object[] { 0 };
        var propertyNames = new[] { "Id" };
        var types = new[] { Substitute.For<IType>() };

        interceptor1.OnFlushDirty(entity, id, currentState, previousState, propertyNames, types).Returns(false);
        interceptor2.OnFlushDirty(entity, id, currentState, previousState, propertyNames, types).Returns(false);

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.OnFlushDirty(entity, id, currentState, previousState, propertyNames, types).ShouldBeFalse();

        interceptor1.Received().OnFlushDirty(entity, id, currentState, previousState, propertyNames, types);
        interceptor2.Received().OnFlushDirty(entity, id, currentState, previousState, propertyNames, types);
    }

    [Test]
    public void Should_call_onflushdirty_true()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();

        var entity = new object();
        var id = new object();
        var currentState = new object[] { 0 };
        var previousState = new object[] { 0 };
        var propertyNames = new[] { "Id" };
        var types = new[] { Substitute.For<IType>() };

        interceptor1.OnFlushDirty(entity, id, currentState, previousState, propertyNames, types).Returns(false);
        interceptor2.OnFlushDirty(entity, id, currentState, previousState, propertyNames, types).Returns(true);

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.OnFlushDirty(entity, id, currentState, previousState, propertyNames, types).ShouldBeTrue();

        interceptor1.Received().OnFlushDirty(entity, id, currentState, previousState, propertyNames, types);
        interceptor2.Received().OnFlushDirty(entity, id, currentState, previousState, propertyNames, types);
    }

    [Test]
    public void Should_call_onload_false()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();

        var entity = new object();
        var id = new object();
        var state = new object[] { 0 };
        var propertyNames = new[] { "Id" };
        var types = new[] { Substitute.For<IType>() };

        interceptor1.OnLoad(entity, id, state, propertyNames, types).Returns(false);
        interceptor2.OnLoad(entity, id, state, propertyNames, types).Returns(false);

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.OnLoad(entity, id, state, propertyNames, types).ShouldBeFalse();

        interceptor1.Received().OnLoad(entity, id, state, propertyNames, types);
        interceptor2.Received().OnLoad(entity, id, state, propertyNames, types);
    }

    [Test]
    public void Should_call_onload_true()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();

        var entity = new object();
        var id = new object();
        var state = new object[] { 0 };
        var propertyNames = new[] { "Id" };
        var types = new[] { Substitute.For<IType>() };

        interceptor1.OnLoad(entity, id, state, propertyNames, types).Returns(false);
        interceptor2.OnLoad(entity, id, state, propertyNames, types).Returns(true);

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.OnLoad(entity, id, state, propertyNames, types).ShouldBeTrue();

        interceptor1.Received().OnLoad(entity, id, state, propertyNames, types);
        interceptor2.Received().OnLoad(entity, id, state, propertyNames, types);
    }

    [Test]
    public void Should_call_onpreparestatement()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();

        var sql = new SqlString();
        var sql1 = SqlString.Parse("SELECT name FROM sys.tables");
        var sql2 = SqlString.Parse("SELECT name FROM sys.tables UNION SELECT name FROM sys.columns");

        interceptor1.OnPrepareStatement(sql).Returns(sql1);
        interceptor2.OnPrepareStatement(sql1).Returns(sql2);

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.OnPrepareStatement(sql).ShouldEqual(sql2);

        interceptor1.Received().OnPrepareStatement(sql);
        interceptor2.Received().OnPrepareStatement(sql1);
    }

    [Test]
    public void Should_call_onsave_false()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();

        var entity = new object();
        var id = new object();
        var state = new object[] { 0 };
        var propertyNames = new[] { "Id" };
        var types = new[] { Substitute.For<IType>() };

        interceptor1.OnSave(entity, id, state, propertyNames, types).Returns(false);
        interceptor2.OnSave(entity, id, state, propertyNames, types).Returns(false);

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.OnSave(entity, id, state, propertyNames, types).ShouldBeFalse();

        interceptor1.Received().OnSave(entity, id, state, propertyNames, types);
        interceptor2.Received().OnSave(entity, id, state, propertyNames, types);
    }

    [Test]
    public void Should_call_onsave_true()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();

        var entity = new object();
        var id = new object();
        var state = new object[] { 0 };
        var propertyNames = new[] { "Id" };
        var types = new[] { Substitute.For<IType>() };

        interceptor1.OnSave(entity, id, state, propertyNames, types).Returns(false);
        interceptor2.OnSave(entity, id, state, propertyNames, types).Returns(true);

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.OnSave(entity, id, state, propertyNames, types).ShouldBeTrue();

        interceptor1.Received().OnSave(entity, id, state, propertyNames, types);
        interceptor2.Received().OnSave(entity, id, state, propertyNames, types);
    }

    [Test]
    public void Should_call_postflush()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();

        var entities = Substitute.For<ICollection>();

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.PostFlush(entities);

        interceptor1.Received().PostFlush(entities);
        interceptor2.Received().PostFlush(entities);
    }

    [Test]
    public void Should_call_preflush()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();

        var entities = Substitute.For<ICollection>();

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.PreFlush(entities);

        interceptor1.Received().PreFlush(entities);
        interceptor2.Received().PreFlush(entities);
    }

    [Test]
    public void Should_call_setsession()
    {
        var interceptor1 = Substitute.For<IInterceptor>();
        var interceptor2 = Substitute.For<IInterceptor>();

        var session = Substitute.For<ISession>();

        var interceptor = new CompositeInterceptor(new[] { interceptor1, interceptor2 });
        interceptor.SetSession(session);

        interceptor1.Received().SetSession(session);
        interceptor2.Received().SetSession(session);
    }
}