Refactored the Kernel registration fluent interface to be more readable, better suppo...

[castle.git] / ActiveRecord / Castle.ActiveRecord / Framework / ActiveRecordStarter.cs

// Copyright 2004-2008 Castle Project - http://www.castleproject.org/
// 
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// 
//     http://www.apache.org/licenses/LICENSE-2.0
// 
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

namespace Castle.ActiveRecord
{
        using System;
        using System.Collections.Generic;
        using System.Data;
        using System.IO;
        using System.Reflection;
        using Castle.ActiveRecord.Framework;
        using Castle.ActiveRecord.Framework.Config;
        using Castle.ActiveRecord.Framework.Internal;
        using Castle.ActiveRecord.Framework.Scopes;
        using Castle.Core.Configuration;
        using NHibernate.Cfg;
        using Iesi.Collections;
        using NHibernate.Expressions;
        using NHibernate.Tool.hbm2ddl;
        using Environment=NHibernate.Cfg.Environment;

        /// <summary>
        /// Delegate for use in <see cref="ActiveRecordStarter.SessionFactoryHolderCreated"/>
        /// </summary>
        /// <param name="holder"></param>
        public delegate void SessionFactoryHolderDelegate(ISessionFactoryHolder holder);
        
        /// <summary>
        /// Delegate for use in <see cref="ActiveRecordStarter.ModelsCreated"/>
        /// </summary>
        public delegate void ModelsCreatedDelegate(ActiveRecordModelCollection models, IConfigurationSource source);

        /// <summary>
        /// Performs the framework initialization.
        /// </summary>
        /// <remarks>
        /// This class is not thread safe.
        /// </remarks>
        public sealed class ActiveRecordStarter
        {
                private static readonly Object lockConfig = new object();

                private static bool isInitialized = false;

                private static IDictionary<Type, string> registeredTypes;

                /// <summary>
                /// This is saved so one can invoke <c>RegisterTypes</c> later
                /// </summary>
                private static IConfigurationSource configSource;

                /// <summary>
                /// So others frameworks can intercept the 
                /// creation and act on the holder instance
                /// </summary>
                public static event SessionFactoryHolderDelegate SessionFactoryHolderCreated;

                /// <summary>
                /// Allows other frameworks to modify the ActiveRecordModel
                /// before the generation of the NHibernate XML configuration.
                /// As an example, this may be used to rewrite table names to
                /// conform to an application-specific standard.  Since the
                /// configuration source is passed in, it is possible to
                /// determine the underlying database type and make changes
                /// if necessary.
                /// </summary>
                public static event ModelsCreatedDelegate ModelsCreated;

    /// <summary>
    /// Allows other frameworks to modify the ActiveRecordModel
    /// before the generation of the NHibernate XML configuration.
    /// As an example, this may be used to rewrite table names to
    /// conform to an application-specific standard.  Since the
    /// configuration source is passed in, it is possible to
    /// determine the underlying database type and make changes
    /// if necessary.
    /// </summary>
    public static event ModelsCreatedDelegate ModelsValidated;

                /// <summary>
                /// Initialize the mappings using the configuration and 
                /// the list of types
                /// </summary>
                public static void Initialize(IConfigurationSource source, params Type[] types)
                {
                        lock(lockConfig)
                        {
                                if (isInitialized)
                                {
                                        throw new ActiveRecordInitializationException("You can't invoke ActiveRecordStarter.Initialize more than once");
                                }

                                if (source == null)
                                {
                                        throw new ArgumentNullException("source");
                                }
                                if (types == null)
                                {
                                        throw new ArgumentNullException("types");
                                }

                                registeredTypes = new Dictionary<Type, string>();

                                configSource = source;

                                // First initialization
                                ISessionFactoryHolder holder = CreateSessionFactoryHolderImplementation(source);

                                holder.ThreadScopeInfo = CreateThreadScopeInfoImplementation(source);

                                RaiseSessionFactoryHolderCreated(holder);

                                ActiveRecordBase.holder = holder;
                                ActiveRecordModel.type2Model.Clear();
                                ActiveRecordModel.isDebug = source.Debug;
                                ActiveRecordModel.isLazyByDefault = source.IsLazyByDefault;
                                ActiveRecordModel.pluralizeTableNames = source.PluralizeTableNames;

                                // Sets up base configuration
                                SetUpConfiguration(source, typeof(ActiveRecordBase), holder);

                                RegisterTypes(holder, source, types, true);

                                isInitialized = true;
                        }
                }

                /// <summary>
                /// Initialize the mappings using the configuration and 
                /// checking all the types on the specified <c>Assembly</c>
                /// </summary>
                public static void Initialize(Assembly assembly, IConfigurationSource source)
                {
                        List<Type> list = new List<Type>();

                        CollectValidActiveRecordTypesFromAssembly(assembly, list, source);

                        Initialize(source, list.ToArray());
                }

                /// <summary>
                /// Initialize the mappings using the configuration and 
                /// checking all the types on the specified Assemblies
                /// </summary>
                public static void Initialize(Assembly[] assemblies, IConfigurationSource source)
                {
                        List<Type> list = new List<Type>();

                        foreach(Assembly assembly in assemblies)
                        {
                                CollectValidActiveRecordTypesFromAssembly(assembly, list, source);
                        }

                        Initialize(source, list.ToArray());
                }

                /// <summary>
                /// Initializes the framework reading the configuration from
                /// the <c>AppDomain</c> and checking all the types on the executing <c>Assembly</c>
                /// </summary>
                public static void Initialize()
                {
                        IConfigurationSource source = ActiveRecordSectionHandler.Instance;

                        Initialize(Assembly.GetCallingAssembly(), source);
                }

                /// <summary>
                /// Registers new assemblies in ActiveRecord
                /// Usefull for dynamic assembly-adding after initialization
                /// </summary>
                /// <param name="assemblies"></param>
                public static void RegisterAssemblies(params Assembly[] assemblies)
                {
                        List<Type> types = new List<Type>();

                        foreach (Assembly assembly in assemblies)
                        {
                                CollectValidActiveRecordTypesFromAssembly(assembly, types, configSource);
                        }

                        RegisterTypes(types.ToArray());
                }

                /// <summary>
                /// Registers new types in ActiveRecord
                /// Usefull for dynamic type-adding after initialization
                /// </summary>
                /// <param name="types"></param>
                public static void RegisterTypes(params Type[] types)
                {
                        RegisterTypes(ActiveRecordBase.holder, configSource, types, false);
                }

                /// <summary>
                /// Generates and executes the creation scripts for the database.
                /// </summary>
                public static void CreateSchema()
                {
                        CheckInitialized();

                        foreach(Configuration config in ActiveRecordBase.holder.GetAllConfigurations())
                        {
                                SchemaExport export = CreateSchemaExport(config);

                                try
                                {
                                        export.Create(false, true);
                                }
                                catch(Exception ex)
                                {
                                        throw new ActiveRecordException("Could not create the schema", ex);
                                }
                        }
                }

                /// <summary>
                /// Generates and executes the creation scripts for the database using 
                /// the specified baseClass to know which database it should create the schema for.
                /// </summary>
                public static void CreateSchema(Type baseClass)
                {
                        CheckInitialized();

                        Configuration config = ActiveRecordBase.holder.GetConfiguration(baseClass);

                        SchemaExport export = CreateSchemaExport(config);

                        try
                        {
                                export.Create(false, true);
                        }
                        catch (Exception ex)
                        {
                                throw new ActiveRecordException("Could not create the schema", ex);
                        }
                }

                /// <summary>
                /// Executes the specified script to create/drop/change the database schema
                /// </summary>
                public static void CreateSchemaFromFile(String scriptFileName)
                {
                        CheckInitialized();

                        CreateSchemaFromFile(scriptFileName, ActiveRecordBase.holder.CreateSession(typeof(ActiveRecordBase)).Connection);
                }

                /// <summary>
                /// Executes the specified script to create/drop/change the database schema
                /// against the specified database connection
                /// </summary>
                public static void CreateSchemaFromFile(String scriptFileName, IDbConnection connection)
                {
                        CheckInitialized();

                        if (connection == null)
                        {
                                throw new ArgumentNullException("connection");
                        }

                        String[] parts = ARSchemaCreator.OpenFileAndStripContents(scriptFileName);
                        ARSchemaCreator.ExecuteScriptParts(connection, parts);
                }

                /// <summary>
                /// Generates and executes the Drop scripts for the database.
                /// </summary>
                public static void DropSchema()
                {
                        CheckInitialized();

                        foreach(Configuration config in ActiveRecordBase.holder.GetAllConfigurations())
                        {
                                SchemaExport export = CreateSchemaExport(config);

                                try
                                {
                                        export.Drop(false, true);
                                }
                                catch(Exception ex)
                                {
                                        throw new ActiveRecordException("Could not drop the schema", ex);
                                }
                        }
                }

                /// <summary>
                /// Generates and executes the Drop scripts for the database using 
                /// the specified baseClass to know which database it should create the scripts for.
                /// </summary>
                public static void DropSchema(Type baseClass)
                {
                        CheckInitialized();

                        Configuration config = ActiveRecordBase.holder.GetConfiguration(baseClass);

                        SchemaExport export = CreateSchemaExport(config);

                        try
                        {
                                export.Drop(false, true);
                        }
                        catch (Exception ex)
                        {
                                throw new ActiveRecordException("Could not drop the schema", ex);
                        }
                }

                /// <summary>
                /// Generates the drop scripts for the database saving them to the supplied file name. 
                /// </summary>
                /// <remarks>
                /// If ActiveRecord was configured to access more than one database, a file is going
                /// to be generate for each, based on the path and the <c>fileName</c> specified.
                /// </remarks>
                public static void GenerateDropScripts(String fileName)
                {
                        CheckInitialized();

                        bool isFirstExport = true;
                        int fileCount = 1;

                        foreach(Configuration config in ActiveRecordBase.holder.GetAllConfigurations())
                        {
                                SchemaExport export = CreateSchemaExport(config);

                                try
                                {
                                        export.SetOutputFile(isFirstExport ? fileName : CreateAnotherFile(fileName, fileCount++));
                                        export.Drop(false, false);
                                }
                                catch(Exception ex)
                                {
                                        throw new ActiveRecordException("Could not drop the schema", ex);
                                }

                                isFirstExport = false;
                        }
                }

                /// <summary>
                /// Generates the drop scripts for the database saving them to the supplied file name. 
                /// The baseType is used to identify which database should we act upon.
                /// </summary>
                public static void GenerateDropScripts(Type baseType, String fileName)
                {
                        CheckInitialized();

                        Configuration config = ActiveRecordBase.holder.GetConfiguration(baseType);

                        SchemaExport export = CreateSchemaExport(config);

                        try
                        {
                                export.SetOutputFile(fileName);
                                export.Drop(false, false);
                        }
                        catch (Exception ex)
                        {
                                throw new ActiveRecordException("Could not generate drop schema scripts", ex);
                        }
                }

                /// <summary>
                /// Generates the creation scripts for the database
                /// </summary>
                /// <remarks>
                /// If ActiveRecord was configured to access more than one database, a file is going
                /// to be generate for each, based on the path and the <c>fileName</c> specified.
                /// </remarks>
                public static void GenerateCreationScripts(String fileName)
                {
                        CheckInitialized();

                        bool isFirstExport = true;
                        int fileCount = 1;

                        foreach(Configuration config in ActiveRecordBase.holder.GetAllConfigurations())
                        {
                                SchemaExport export = CreateSchemaExport(config);

                                try
                                {
                                        export.SetOutputFile(isFirstExport ? fileName : CreateAnotherFile(fileName, fileCount++));
                                        export.Create(false, false);
                                }
                                catch(Exception ex)
                                {
                                        throw new ActiveRecordException("Could not create the schema", ex);
                                }

                                isFirstExport = false;
                        }
                }

                /// <summary>
                /// Generates the creation scripts for the database
                /// The baseType is used to identify which database should we act upon.
                /// </summary>
                public static void GenerateCreationScripts(Type baseType, String fileName)
                {
                        CheckInitialized();

                        Configuration config = ActiveRecordBase.holder.GetConfiguration(baseType);

                        SchemaExport export = CreateSchemaExport(config);

                        try
                        {
                                export.SetOutputFile(fileName);
                                export.Create(false, false);
                        }
                        catch (Exception ex)
                        {
                                throw new ActiveRecordException("Could not create the schema scripts", ex);
                        }
                }

                /// <summary>
                /// Intended to be used only by test cases
                /// </summary>
                public static void ResetInitializationFlag()
                {
                        isInitialized = false;
                }

                private static ActiveRecordModelCollection BuildModels(ISessionFactoryHolder holder,
                                                                                                                           IConfigurationSource source,
                                                                                                                           IEnumerable<Type> types, bool ignoreProblematicTypes)
                {
                        ActiveRecordModelBuilder builder = new ActiveRecordModelBuilder();

                        ActiveRecordModelCollection models = builder.Models;

                        foreach(Type type in types)
                        {
                                if (ShouldIgnoreType(type))
                                {
                                        if (ignoreProblematicTypes)
                                        {
                                                continue;
                                        }
                                        else
                                        {
                                                throw new ActiveRecordException(
                                                        String.Format("Type `{0}` is registered already", type.FullName));
                                        }
                                } 
                                else if (IsConfiguredAsRootType(type))
                                {
                                        if (TypeDefinesADatabaseBoundary(type)) 
                                        {
                                                SetUpConfiguration(source, type, holder);
                                                continue;
                                        } 
                                        else 
                                        {
                                                throw new ActiveRecordException(
                                                        string.Format(
                                                                "Type `{0}` is not a valid root type.  Make sure it is abstract and does not define a table itself.",
                                                                type.FullName));
                                        }
                                }
                                else if (!IsActiveRecordType(type))
                                {
                                        if (ignoreProblematicTypes)
                                        {
                                                continue;
                                        }
                                        else
                                        {
                                                throw new ActiveRecordException(
                                                        String.Format("Type `{0}` is not an ActiveRecord type. Use ActiveRecordAttributes to define one", type.FullName));
                                        }
                                }

                                ActiveRecordModel model = builder.Create(type);

                                if (model == null)
                                {
                                        throw new ActiveRecordException(
                                                String.Format("ActiveRecordModel for `{0}` could not be created", type.FullName));
                                }

                                registeredTypes.Add(type, String.Empty);
                        }

                        return models;
                }

                private static bool IsConfiguredAsRootType(Type type)
                {
                        return configSource.GetConfiguration(type) != null;
                }

                private static bool TypeDefinesADatabaseBoundary(Type type)
                {
                        return (type.IsAbstract && !IsTypeHierarchyBase(type));
                }

                private static bool ShouldIgnoreType(Type type)
                {
                        return (registeredTypes.ContainsKey(type) ||
                                        type == typeof(ActiveRecordBase) ||
                                        type == typeof(ActiveRecordValidationBase) ||
                                        type == typeof(ActiveRecordHooksBase));
                }

                private static bool IsTypeHierarchyBase(ICustomAttributeProvider type)
                {
                        if (type.IsDefined(typeof(JoinedBaseAttribute), false))
                        {
                                return true;
                        }

                        object[] attrs = type.GetCustomAttributes(typeof(ActiveRecordAttribute), false);

                        if (attrs != null && attrs.Length > 0)
                        {
                                ActiveRecordAttribute att = (ActiveRecordAttribute) attrs[0];

                                return att.DiscriminatorColumn != null;
                        }

                        return false;
                }

                private static void AddXmlToNHibernateCfg(ISessionFactoryHolder holder, ActiveRecordModelCollection models)
                {
                        XmlGenerationVisitor xmlVisitor = new XmlGenerationVisitor();
                        AssemblyXmlGenerator assemblyXmlGenerator = new AssemblyXmlGenerator();
                        ISet assembliesGeneratedXmlFor = new HashedSet();
                        foreach(ActiveRecordModel model in models)
                        {
                                Configuration config = holder.GetConfiguration(holder.GetRootType(model.Type));

                                if (config==null)
                                {
                                        throw new ActiveRecordException(
                                                string.Format(
                                                        "Could not find configuration for {0} or its root type {1} this is usually an indication that the configuration has not been setup correctly.",
                                                        model.Type, holder.GetRootType(model.Type)));
                                }

                                if (!model.IsNestedType && !model.IsDiscriminatorSubClass && !model.IsJoinedSubClass)
                                {
                                        xmlVisitor.Reset();
                                        xmlVisitor.CreateXml(model);

                                        String xml = xmlVisitor.Xml;

                                        if (xml != String.Empty)
                                        {
                                                AddXmlString(config, xml, model);
                                        }
                                }

                                if (!assembliesGeneratedXmlFor.Contains(model.Type.Assembly))
                                {
                                        assembliesGeneratedXmlFor.Add(model.Type.Assembly);

                                        string[] configurations = assemblyXmlGenerator.CreateXmlConfigurations(model.Type.Assembly);
                                        
                                        foreach(string xml in configurations)
                                        {
                                                if (xml != string.Empty)
                                                {
                                                        config.AddXmlString(xml);
                                                }
                                        }
                                }
                        }
                }

                private static void AddXmlString(Configuration config, string xml, ActiveRecordModel model)
                {
                        try
                        {
                                config.AddXmlString(xml);
                        }
                        catch(Exception ex)
                        {
                                throw new ActiveRecordException("Error adding information from class " + model.Type.FullName + " to NHibernate. Check the inner exception for more information", ex);
                        }
                }

                private static Type[] GetExportedTypesFromAssembly(Assembly assembly)
                {
                        try
                        {
                                return assembly.GetExportedTypes();
                        }
                        catch(Exception ex)
                        {
                                throw new ActiveRecordInitializationException(
                                        "Error while loading the exported types from the assembly: " + assembly.FullName, ex);
                        }
                }

                private static SchemaExport CreateSchemaExport(Configuration cfg)
                {
                        return new SchemaExport(cfg);
                }

                /// <summary>
                /// Return true if the type has a [ActiveRecord] attribute
                /// </summary>
                private static bool IsActiveRecordType(ICustomAttributeProvider type)
                {
                        return type.IsDefined(typeof(ActiveRecordAttribute), false);
                }

                private static void CheckInitialized()
                {
                        if (ActiveRecordBase.holder == null)
                        {
                                throw new ActiveRecordException("Framework must be Initialized first.");
                        }
                }

                private static Configuration CreateConfiguration(IConfiguration config)
                {
                        // hammett comments: I'm gonna test this off for a while
                        // ayende comments:     removing this means that tests that using generic entities as base class will break
                        //                                      NH do not support generic entities at the moemnt
                        Environment.UseReflectionOptimizer = false;

                        Configuration cfg = new Configuration();

                        foreach(IConfiguration childConfig in config.Children)
                        {
                                cfg.Properties.Add(childConfig.Name, childConfig.Value);
                        }

                        return cfg;
                }

                private static void SetUpConfiguration(IConfigurationSource source, Type type, ISessionFactoryHolder holder)
                {
                        IConfiguration config = source.GetConfiguration(type);

                        if (config != null)
                        {
                                Configuration nconf = CreateConfiguration(config);

                                if (source.NamingStrategyImplementation != null)
                                {
                                        Type namingStrategyType = source.NamingStrategyImplementation;

                                        if (!typeof(INamingStrategy).IsAssignableFrom(namingStrategyType))
                                        {
                                                String message =
                                                        String.Format("The specified type {0} does " + "not implement the interface INamingStrategy",
                                                                                  namingStrategyType.FullName);

                                                throw new ActiveRecordException(message);
                                        }

                                        nconf.SetNamingStrategy((INamingStrategy)Activator.CreateInstance(namingStrategyType));
                                }

                                holder.Register(type, nconf);
                        }
                }

                private static void RaiseSessionFactoryHolderCreated(ISessionFactoryHolder holder)
                {
                        if (SessionFactoryHolderCreated != null)
                        {
                                SessionFactoryHolderCreated(holder);
                        }
                }

                private static ISessionFactoryHolder CreateSessionFactoryHolderImplementation(IConfigurationSource source)
                {
                        if (source.SessionFactoryHolderImplementation != null)
                        {
                                Type sessionFactoryHolderType = source.SessionFactoryHolderImplementation;

                                if (!typeof(ISessionFactoryHolder).IsAssignableFrom(sessionFactoryHolderType))
                                {
                                        String message =
                                                String.Format("The specified type {0} does " + "not implement the interface ISessionFactoryHolder",
                                                                          sessionFactoryHolderType.FullName);

                                        throw new ActiveRecordException(message);
                                }

                                return (ISessionFactoryHolder) Activator.CreateInstance(sessionFactoryHolderType);
                        }
                        else
                        {
                                return new SessionFactoryHolder();
                        }
                }

                private static void RegisterTypes(ISessionFactoryHolder holder, IConfigurationSource source, IEnumerable<Type> types,
                                                                                  bool ignoreProblematicTypes)
                {
                        lock(lockConfig)
                        {
                                ActiveRecordModelCollection models = BuildModels(holder, source, types, ignoreProblematicTypes);

                                GraphConnectorVisitor connectorVisitor = new GraphConnectorVisitor(models);
                                connectorVisitor.VisitNodes(models);

                                ModelsCreatedDelegate modelsCreatedHandler = ModelsCreated;
                                if (modelsCreatedHandler != null)
                                {
                                        modelsCreatedHandler(models, source);
                                }

                                SemanticVerifierVisitor semanticVisitor = new SemanticVerifierVisitor(models);
                                semanticVisitor.VisitNodes(models);

                                ModelsCreatedDelegate modelsValidatedHandler = ModelsValidated;
                                if(modelsValidatedHandler != null)
                                {
                                        modelsValidatedHandler(models, source);
                                }

                                AddXmlToNHibernateCfg(holder, models);

                                if (source.VerifyModelsAgainstDBSchema)
                                {
                                        VerifySchema(models);
                                }
                        }
                }

                private static void VerifySchema(ActiveRecordModelCollection models)
                {
                        foreach(ActiveRecordModel model in models)
                        {
                                if (!model.Type.IsAbstract)
                                {
                                        try
                                        {
                                                ActiveRecordMediator.FindAll(model.Type, Expression.Sql("1=0"));
                                        }
                                        catch (Exception ex)
                                        {
                                                throw new ActiveRecordException("Error verifying the schema for model " + model.Type.Name, ex);
                                        }
                                }
                        }
                }

                private static IThreadScopeInfo CreateThreadScopeInfoImplementation(IConfigurationSource source)
                {
                        if (source.ThreadScopeInfoImplementation != null)
                        {
                                Type threadScopeType = source.ThreadScopeInfoImplementation;

                                if (!typeof(IThreadScopeInfo).IsAssignableFrom(threadScopeType))
                                {
                                        String message =
                                                String.Format("The specified type {0} does " + "not implement the interface IThreadScopeInfo",
                                                                          threadScopeType.FullName);

                                        throw new ActiveRecordInitializationException(message);
                                }

                                return (IThreadScopeInfo) Activator.CreateInstance(threadScopeType);
                        }
                        else
                        {
                                return new ThreadScopeInfo();
                        }
                }

                /// <summary>
                /// Retrieve all classes decorated with ActiveRecordAttribute or that have been configured
                /// as a AR base class.
                /// </summary>
                /// <param name="assembly">Assembly to retrieve types from</param>
                /// <param name="list">Array to store retrieved types in</param>
                /// <param name="source">IConfigurationSource to inspect AR base declarations from</param>
                private static void CollectValidActiveRecordTypesFromAssembly(Assembly assembly, ICollection<Type> list,
                                                                                                                                          IConfigurationSource source)
                {
                        Type[] types = GetExportedTypesFromAssembly(assembly);

                        foreach(Type type in types)
                        {
                                if (IsActiveRecordType(type) || source.GetConfiguration(type) != null)
                                {
                                        list.Add(type);
                                }
                        }
                }

                /// <summary>
                /// Generate a file name based on the original file name specified, using the 
                /// count to give it some order.
                /// </summary>
                /// <param name="originalFileName"></param>
                /// <param name="fileCount"></param>
                /// <returns></returns>
                private static string CreateAnotherFile(string originalFileName, int fileCount)
                {
                        string path = Path.GetDirectoryName(originalFileName);
                        string fileName = Path.GetFileNameWithoutExtension(originalFileName);
                        string extension = Path.GetExtension(originalFileName);

                        return Path.Combine(path, string.Format("{0}_{1}{2}", fileName, fileCount, extension));
                }
        }
}