NOP源码分析六--实体、数据的分层与处理。

也许我应该先研究下架构，但现在还是接着研究NOP吧，不能半途而废啊。

之前粗略研究过如何添加一个属性，http://www.cnblogs.com/runit/p/3842611.html，基本一样。我们以ScheduleTask为例。

下面是一个实体类，没有多余功能，就是提供了实体类的各个属性。

namespace Nop.Core.Domain.Tasks
{
    public class ScheduleTask : BaseEntity
    {
        /// <summary>
        /// Gets or sets the name
        /// </summary>
        public string Name { get; set; }

        /// <summary>
        /// Gets or sets the run period (in seconds)
        /// </summary>
        public int Seconds { get; set; }

        /// <summary>
        /// Gets or sets the type of appropriate ITask class
        /// </summary>
        public string Type { get; set; }

        /// <summary>
        /// Gets or sets the value indicating whether a task is enabled
        /// </summary>
        public bool Enabled { get; set; }

        /// <summary>
        /// Gets or sets the value indicating whether a task should be stopped on some error
        /// </summary>
        public bool StopOnError { get; set; }

        public DateTime? LastStartUtc { get; set; }

        public DateTime? LastEndUtc { get; set; }

        public DateTime? LastSuccessUtc { get; set; }
    }
}

下面就是关系映射类，这个类就用到了上面的类，把上面的类映射到数据库相应的表名，以及Key是哪一个，哪些属性不能为空，以及长度上面的都在这里设定。

前面我们提到的NopObjectContext（DBContext） 就是通过反射得到所有的NopEntityTypeConfiguration子类，并进行增删改查的。

namespace Nop.Data.Mapping.Tasks
{
    public partial class ScheduleTaskMap : NopEntityTypeConfiguration<ScheduleTask>
    {
        public ScheduleTaskMap()
        {
            this.ToTable("ScheduleTask");
            this.HasKey(t => t.Id);
            this.Property(t => t.Name).IsRequired();
            this.Property(t => t.Type).IsRequired();
        }
    }
}

上面2个是底层的，下面我们介绍界面层的。代码如下：

namespace Nop.Admin.Models.Tasks
{
    [Validator(typeof(ScheduleTaskValidator))]
    public partial class ScheduleTaskModel : BaseNopEntityModel
    {
        [NopResourceDisplayName("Admin.System.ScheduleTasks.Name")]
        [AllowHtml]
        public string Name { get; set; }

        [NopResourceDisplayName("Admin.System.ScheduleTasks.Seconds")]
        public int Seconds { get; set; }

        [NopResourceDisplayName("Admin.System.ScheduleTasks.Enabled")]
        public bool Enabled { get; set; }

        [NopResourceDisplayName("Admin.System.ScheduleTasks.StopOnError")]
        public bool StopOnError { get; set; }

        [NopResourceDisplayName("Admin.System.ScheduleTasks.LastStart")]
        public string LastStartUtc { get; set; }

        [NopResourceDisplayName("Admin.System.ScheduleTasks.LastEnd")]
        public string LastEndUtc { get; set; }

        [NopResourceDisplayName("Admin.System.ScheduleTasks.LastSuccess")]
        public string LastSuccessUtc { get; set; }
    }
}

这里我们看到，这个类做了Nop.Core.Domain实体类的相同属性，也就是重复了，这应该就是为了解耦、分离。

同时他还有NopResourceDisplayName属性，用于告诉界面如何显示，AllowHtml，是否允许HTML等。

在类的开始 有如下代码：[Validator(typeof(ScheduleTaskValidator))] ，这个应该就是验证类的了。我们看Ixia这个类

namespace Nop.Admin.Validators.Tasks
{
    public class ScheduleTaskValidator : BaseNopValidator<ScheduleTaskModel>
    {
        public ScheduleTaskValidator(ILocalizationService localizationService)
        {
            RuleFor(x => x.Name).NotEmpty().WithMessage(localizationService.GetResource("Admin.System.ScheduleTasks.Name.Required"));
            RuleFor(x => x.Seconds).GreaterThan(0).WithMessage(localizationService.GetResource("Admin.System.ScheduleTasks.Seconds.Positive"));
        }
    }
}

果然是验证代码，如果验证失败，则返回什么等。用到的验证是FluentValidation，http://www.cnblogs.com/whitewolf/archive/2012/05/27/2520593.html

http://www.cnblogs.com/jes_shaw/p/3380940.html，上面是学习的连接，验证，及验证集成类的代码如下，就是一个FluentValidation验证。

namespace Nop.Admin.Validators.Tasks
{
    public class ScheduleTaskValidator : BaseNopValidator<ScheduleTaskModel>
    {
        public ScheduleTaskValidator(ILocalizationService localizationService)
        {
            RuleFor(x => x.Name).NotEmpty().WithMessage(localizationService.GetResource("Admin.System.ScheduleTasks.Name.Required"));
            RuleFor(x => x.Seconds).GreaterThan(0).WithMessage(localizationService.GetResource("Admin.System.ScheduleTasks.Seconds.Positive"));
        }
    }
}

继承自如下类，如下类继承自FluentValidation的标准验证抽象类，实现构造内验证。

namespace Nop.Web.Framework.Validators
{
    public abstract class BaseNopValidator<T> : AbstractValidator<T> where T : class
    {
        protected BaseNopValidator()
        {
            PostInitialize();
        }

        /// <summary>
        /// Developers can override this method in custom partial classes
        /// in order to add some custom initialization code to constructors
        /// </summary>
        protected virtual void PostInitialize()
        {
            
        }
    }
}

我们注意到，验证类用到了ILocalizationService类，通过DependencyRegistrar类查到其实现类是LocalizationService，这个类还挺复杂，慢慢来。

namespace Nop.Services.Localization
{
    /// <summary>
    /// Provides information about localization
    /// </summary>
    public partial class LocalizationService : ILocalizationService
    {
        #region Constants

        /// <summary>
        /// Key for caching
        /// </summary>
        /// <remarks>
        /// {0} : language ID
        /// </remarks>
        private const string LOCALSTRINGRESOURCES_ALL_KEY = "Nop.lsr.all-{0}";
        /// <summary>
        /// Key for caching
        /// </summary>
        /// <remarks>
        /// {0} : language ID
        /// {1} : resource key
        /// </remarks>
        private const string LOCALSTRINGRESOURCES_BY_RESOURCENAME_KEY = "Nop.lsr.{0}-{1}";
        /// <summary>
        /// Key pattern to clear cache
        /// </summary>
        private const string LOCALSTRINGRESOURCES_PATTERN_KEY = "Nop.lsr.";

        #endregion

        #region Fields

        private readonly IRepository<LocaleStringResource> _lsrRepository;
        private readonly IWorkContext _workContext;
        private readonly ILogger _logger;
        private readonly ILanguageService _languageService;
        private readonly ICacheManager _cacheManager;
        private readonly IDataProvider _dataProvider;
        private readonly IDbContext _dbContext;
        private readonly CommonSettings _commonSettings;
        private readonly LocalizationSettings _localizationSettings;
        private readonly IEventPublisher _eventPublisher;

        #endregion

        #region Ctor

        /// <summary>
        /// Ctor
        /// </summary>
        /// <param name="cacheManager">Cache manager</param>
        /// <param name="logger">Logger</param>
        /// <param name="workContext">Work context</param>
        /// <param name="lsrRepository">Locale string resource repository</param>
        /// <param name="languageService">Language service</param>
        /// <param name="dataProvider">Data provider</param>
        /// <param name="dbContext">Database Context</param>
        /// <param name="commonSettings">Common settings</param>
        /// <param name="localizationSettings">Localization settings</param>
        /// <param name="eventPublisher">Event published</param>
        public LocalizationService(ICacheManager cacheManager,
            ILogger logger, IWorkContext workContext,
            IRepository<LocaleStringResource> lsrRepository, 
            ILanguageService languageService,
            IDataProvider dataProvider, IDbContext dbContext, CommonSettings commonSettings,
            LocalizationSettings localizationSettings, IEventPublisher eventPublisher)
        {
            this._cacheManager = cacheManager;
            this._logger = logger;
            this._workContext = workContext;
            this._lsrRepository = lsrRepository;
            this._languageService = languageService;
            this._dataProvider = dataProvider;
            this._dbContext = dbContext;
            this._commonSettings = commonSettings;
            this._dataProvider = dataProvider;
            this._dbContext = dbContext;
            this._commonSettings = commonSettings;
            this._localizationSettings = localizationSettings;
            this._eventPublisher = eventPublisher;
        }

        #endregion

        #region Methods

        /// <summary>
        /// Deletes a locale string resource
        /// </summary>
        /// <param name="localeStringResource">Locale string resource</param>
        public virtual void DeleteLocaleStringResource(LocaleStringResource localeStringResource)
        {
            if (localeStringResource == null)
                throw new ArgumentNullException("localeStringResource");

            _lsrRepository.Delete(localeStringResource);

            //cache
            _cacheManager.RemoveByPattern(LOCALSTRINGRESOURCES_PATTERN_KEY);

            //event notification
            _eventPublisher.EntityDeleted(localeStringResource);
        }

        /// <summary>
        /// Gets a locale string resource
        /// </summary>
        /// <param name="localeStringResourceId">Locale string resource identifier</param>
        /// <returns>Locale string resource</returns>
        public virtual LocaleStringResource GetLocaleStringResourceById(int localeStringResourceId)
        {
            if (localeStringResourceId == 0)
                return null;

            return _lsrRepository.GetById(localeStringResourceId);
        }

        /// <summary>
        /// Gets a locale string resource
        /// </summary>
        /// <param name="resourceName">A string representing a resource name</param>
        /// <returns>Locale string resource</returns>
        public virtual LocaleStringResource GetLocaleStringResourceByName(string resourceName)
        {
            if (_workContext.WorkingLanguage != null)
                return GetLocaleStringResourceByName(resourceName, _workContext.WorkingLanguage.Id);

            return null;
        }

        /// <summary>
        /// Gets a locale string resource
        /// </summary>
        /// <param name="resourceName">A string representing a resource name</param>
        /// <param name="languageId">Language identifier</param>
        /// <param name="logIfNotFound">A value indicating whether to log error if locale string resource is not found</param>
        /// <returns>Locale string resource</returns>
        public virtual LocaleStringResource GetLocaleStringResourceByName(string resourceName, int languageId,
            bool logIfNotFound = true)
        {
            var query = from lsr in _lsrRepository.Table
                        orderby lsr.ResourceName
                        where lsr.LanguageId == languageId && lsr.ResourceName == resourceName
                        select lsr;
            var localeStringResource = query.FirstOrDefault();

            if (localeStringResource == null && logIfNotFound)
                _logger.Warning(string.Format("Resource string ({0}) not found. Language ID = {1}", resourceName, languageId));
            return localeStringResource;
        }

        /// <summary>
        /// Gets all locale string resources by language identifier
        /// </summary>
        /// <param name="languageId">Language identifier</param>
        /// <returns>Locale string resources</returns>
        public virtual IList<LocaleStringResource> GetAllResources(int languageId)
        {
            var query = from l in _lsrRepository.Table
                        orderby l.ResourceName
                        where l.LanguageId == languageId
                        select l;
            var locales = query.ToList();
            return locales;
        }

        /// <summary>
        /// Inserts a locale string resource
        /// </summary>
        /// <param name="localeStringResource">Locale string resource</param>
        public virtual void InsertLocaleStringResource(LocaleStringResource localeStringResource)
        {
            if (localeStringResource == null)
                throw new ArgumentNullException("localeStringResource");
            
            _lsrRepository.Insert(localeStringResource);

            //cache
            _cacheManager.RemoveByPattern(LOCALSTRINGRESOURCES_PATTERN_KEY);

            //event notification
            _eventPublisher.EntityInserted(localeStringResource);
        }

        /// <summary>
        /// Updates the locale string resource
        /// </summary>
        /// <param name="localeStringResource">Locale string resource</param>
        public virtual void UpdateLocaleStringResource(LocaleStringResource localeStringResource)
        {
            if (localeStringResource == null)
                throw new ArgumentNullException("localeStringResource");

            _lsrRepository.Update(localeStringResource);

            //cache
            _cacheManager.RemoveByPattern(LOCALSTRINGRESOURCES_PATTERN_KEY);

            //event notification
            _eventPublisher.EntityUpdated(localeStringResource);
        }

        /// <summary>
        /// Gets all locale string resources by language identifier
        /// </summary>
        /// <param name="languageId">Language identifier</param>
        /// <returns>Locale string resources</returns>
        public virtual Dictionary<string, KeyValuePair<int,string>> GetAllResourceValues(int languageId)
        {
            string key = string.Format(LOCALSTRINGRESOURCES_ALL_KEY, languageId);
            return _cacheManager.Get(key, () =>
            {
                //we use no tracking here for performance optimization
                //anyway records are loaded only for read-only operations
                var query = from l in _lsrRepository.TableNoTracking
                            orderby l.ResourceName
                            where l.LanguageId == languageId
                            select l;
                var locales = query.ToList();
                //format: <name, <id, value>>
                var dictionary = new Dictionary<string, KeyValuePair<int, string>>();
                foreach (var locale in locales)
                {
                    var resourceName = locale.ResourceName.ToLowerInvariant();
                    if (!dictionary.ContainsKey(resourceName))
                        dictionary.Add(resourceName, new KeyValuePair<int, string>(locale.Id, locale.ResourceValue));
                }
                return dictionary;
            });
        }

        /// <summary>
        /// Gets a resource string based on the specified ResourceKey property.
        /// </summary>
        /// <param name="resourceKey">A string representing a ResourceKey.</param>
        /// <returns>A string representing the requested resource string.</returns>
        public virtual string GetResource(string resourceKey)
        {
            if (_workContext.WorkingLanguage != null)
                return GetResource(resourceKey, _workContext.WorkingLanguage.Id);
            
            return "";
        }
        
        /// <summary>
        /// Gets a resource string based on the specified ResourceKey property.
        /// </summary>
        /// <param name="resourceKey">A string representing a ResourceKey.</param>
        /// <param name="languageId">Language identifier</param>
        /// <param name="logIfNotFound">A value indicating whether to log error if locale string resource is not found</param>
        /// <param name="defaultValue">Default value</param>
        /// <param name="returnEmptyIfNotFound">A value indicating whether an empty string will be returned if a resource is not found and default value is set to empty string</param>
        /// <returns>A string representing the requested resource string.</returns>
        public virtual string GetResource(string resourceKey, int languageId,
            bool logIfNotFound = true, string defaultValue = "", bool returnEmptyIfNotFound = false)
        {
            string result = string.Empty;
            if (resourceKey == null)
                resourceKey = string.Empty;
            resourceKey = resourceKey.Trim().ToLowerInvariant();
            if (_localizationSettings.LoadAllLocaleRecordsOnStartup)
            {
                //load all records (we know they are cached)
                var resources = GetAllResourceValues(languageId);
                if (resources.ContainsKey(resourceKey))
                {
                    result = resources[resourceKey].Value;
                }
            }
            else
            {
                //gradual loading
                string key = string.Format(LOCALSTRINGRESOURCES_BY_RESOURCENAME_KEY, languageId, resourceKey);
                string lsr = _cacheManager.Get(key, () =>
                {
                    var query = from l in _lsrRepository.Table
                                where l.ResourceName == resourceKey
                                && l.LanguageId == languageId
                                select l.ResourceValue;
                    return query.FirstOrDefault();
                });

                if (lsr != null) 
                    result = lsr;
            }
            if (String.IsNullOrEmpty(result))
            {
                if (logIfNotFound)
                    _logger.Warning(string.Format("Resource string ({0}) is not found. Language ID = {1}", resourceKey, languageId));
                
                if (!String.IsNullOrEmpty(defaultValue))
                {
                    result = defaultValue;
                }
                else
                {
                    if (!returnEmptyIfNotFound)
                        result = resourceKey;
                }
            }
            return result;
        }

        /// <summary>
        /// Export language resources to xml
        /// </summary>
        /// <param name="language">Language</param>
        /// <returns>Result in XML format</returns>
        public virtual string ExportResourcesToXml(Language language)
        {
            if (language == null)
                throw new ArgumentNullException("language");
            var sb = new StringBuilder();
            var stringWriter = new StringWriter(sb);
            var xmlWriter = new XmlTextWriter(stringWriter);
            xmlWriter.WriteStartDocument();
            xmlWriter.WriteStartElement("Language");
            xmlWriter.WriteAttributeString("Name", language.Name);


            var resources = GetAllResources(language.Id);
            foreach (var resource in resources)
            {
                xmlWriter.WriteStartElement("LocaleResource");
                xmlWriter.WriteAttributeString("Name", resource.ResourceName);
                xmlWriter.WriteElementString("Value", null, resource.ResourceValue);
                xmlWriter.WriteEndElement();
            }

            xmlWriter.WriteEndElement();
            xmlWriter.WriteEndDocument();
            xmlWriter.Close();
            return stringWriter.ToString();
        }

        /// <summary>
        /// Import language resources from XML file
        /// </summary>
        /// <param name="language">Language</param>
        /// <param name="xml">XML</param>
        public virtual void ImportResourcesFromXml(Language language, string xml)
        {
            if (language == null)
                throw new ArgumentNullException("language");

            if (String.IsNullOrEmpty(xml))
                return;
            if (_commonSettings.UseStoredProceduresIfSupported && _dataProvider.StoredProceduredSupported)
            {
                //SQL 2005 insists that your XML schema incoding be in UTF-16.
                //Otherwise, you'll get "XML parsing: line 1, character XXX, unable to switch the encoding"
                //so let's remove XML declaration
                var inDoc = new XmlDocument();
                inDoc.LoadXml(xml);
                var sb = new StringBuilder();
                using (var xWriter = XmlWriter.Create(sb, new XmlWriterSettings { OmitXmlDeclaration = true }))
                {
                    inDoc.Save(xWriter);
                    xWriter.Close();
                }
                var outDoc = new XmlDocument();
                outDoc.LoadXml(sb.ToString());
                xml = outDoc.OuterXml;

                //stored procedures are enabled and supported by the database.
                var pLanguageId = _dataProvider.GetParameter();
                pLanguageId.ParameterName = "LanguageId";
                pLanguageId.Value = language.Id;
                pLanguageId.DbType = DbType.Int32;

                var pXmlPackage = _dataProvider.GetParameter();
                pXmlPackage.ParameterName = "XmlPackage";
                pXmlPackage.Value = xml;
                pXmlPackage.DbType = DbType.Xml;

                //long-running query. specify timeout (600 seconds)
                _dbContext.ExecuteSqlCommand("EXEC [LanguagePackImport] @LanguageId, @XmlPackage", false, 600, pLanguageId, pXmlPackage);
            }
            else
            {
                //stored procedures aren't supported
                var xmlDoc = new XmlDocument();
                xmlDoc.LoadXml(xml);

                var nodes = xmlDoc.SelectNodes(@"//Language/LocaleResource");
                foreach (XmlNode node in nodes)
                {
                    string name = node.Attributes["Name"].InnerText.Trim();
                    string value = "";
                    var valueNode = node.SelectSingleNode("Value");
                    if (valueNode != null)
                        value = valueNode.InnerText;

                    if (String.IsNullOrEmpty(name))
                        continue;

                    //do not use "Insert"/"Update" methods because they clear cache
                    //let's bulk insert
                    var resource = language.LocaleStringResources.FirstOrDefault(x => x.ResourceName.Equals(name, StringComparison.InvariantCultureIgnoreCase));
                    if (resource != null)
                        resource.ResourceValue = value;
                    else
                    {
                        language.LocaleStringResources.Add(
                            new LocaleStringResource
                            {
                                ResourceName = name,
                                ResourceValue = value
                            });
                    }
                }
                _languageService.UpdateLanguage(language);
            }

            //clear cache
            _cacheManager.RemoveByPattern(LOCALSTRINGRESOURCES_PATTERN_KEY);
        }

        #endregion
    }
}

好复杂，不是么？我们看一下他的构造如下：

public LocalizationService(ICacheManager cacheManager,
            ILogger logger, IWorkContext workContext,
            IRepository<LocaleStringResource> lsrRepository, 
            ILanguageService languageService,
            IDataProvider dataProvider, IDbContext dbContext, CommonSettings commonSettings,
            LocalizationSettings localizationSettings, IEventPublisher eventPublisher)
        {
            this._cacheManager = cacheManager;
            this._logger = logger;
            this._workContext = workContext;
            this._lsrRepository = lsrRepository;
            this._languageService = languageService;
            this._dataProvider = dataProvider;
            this._dbContext = dbContext;
            this._commonSettings = commonSettings;
            this._dataProvider = dataProvider;
            this._dbContext = dbContext;
            this._commonSettings = commonSettings;
            this._localizationSettings = localizationSettings;
            this._eventPublisher = eventPublisher;
        }

东西太多，比如：缓存管理、日志、工作上下文、存储仓库、数据提供、。。。。很多我们都没有研究，看一下就行了。我们略过这里。用到什么再研究也不晚。我们找到GetResource方法：

/// <summary>
        /// Gets a resource string based on the specified ResourceKey property.
        /// </summary>
        /// <param name="resourceKey">A string representing a ResourceKey.</param>
        /// <returns>A string representing the requested resource string.</returns>
        public virtual string GetResource(string resourceKey)
        {
            if (_workContext.WorkingLanguage != null)
                return GetResource(resourceKey, _workContext.WorkingLanguage.Id);
            
            return "";
        }

用到了IWorkContext 查找依赖注册的是：WebWorkContext，查看代码 构造函数依然复杂，略过。。。。查看WorkingLanguage方法。

/// <summary>
        /// Get or set current user working language
        /// </summary>
        public virtual Language WorkingLanguage
        {
            get
            {
                if (_cachedLanguage != null)
                    return _cachedLanguage;
                
                Language detectedLanguage = null;
                if (_localizationSettings.SeoFriendlyUrlsForLanguagesEnabled)
                {
                    //get language from URL
                    detectedLanguage = GetLanguageFromUrl();
                }
                if (detectedLanguage == null && _localizationSettings.AutomaticallyDetectLanguage)
                {
                    //get language from browser settings
                    //but we do it only once
                    if (!this.CurrentCustomer.GetAttribute<bool>(SystemCustomerAttributeNames.LanguageAutomaticallyDetected, 
                        _genericAttributeService, _storeContext.CurrentStore.Id))
                    {
                        detectedLanguage = GetLanguageFromBrowserSettings();
                        if (detectedLanguage != null)
                        {
                            _genericAttributeService.SaveAttribute(this.CurrentCustomer, SystemCustomerAttributeNames.LanguageAutomaticallyDetected,
                                 true, _storeContext.CurrentStore.Id);
                        }
                    }
                }
                if (detectedLanguage != null)
                {
                    //the language is detected. now we need to save it
                    if (this.CurrentCustomer.GetAttribute<int>(SystemCustomerAttributeNames.LanguageId,
                        _genericAttributeService, _storeContext.CurrentStore.Id) != detectedLanguage.Id)
                    {
                        _genericAttributeService.SaveAttribute(this.CurrentCustomer, SystemCustomerAttributeNames.LanguageId,
                            detectedLanguage.Id, _storeContext.CurrentStore.Id);
                    }
                }

                var allLanguages = _languageService.GetAllLanguages(storeId: _storeContext.CurrentStore.Id);
                //find current customer language
                var languageId = this.CurrentCustomer.GetAttribute<int>(SystemCustomerAttributeNames.LanguageId,
                    _genericAttributeService, _storeContext.CurrentStore.Id);
                var language = allLanguages.FirstOrDefault(x => x.Id == languageId);
                if (language == null)
                {
                    //it not specified, then return the first (filtered by current store) found one
                    language = allLanguages.FirstOrDefault();
                }
                if (language == null)
                {
                    //it not specified, then return the first found one
                    language = _languageService.GetAllLanguages().FirstOrDefault();
                }

                //cache
                _cachedLanguage = language;
                return _cachedLanguage;
            }
            set
            {
                var languageId = value != null ? value.Id : 0;
                _genericAttributeService.SaveAttribute(this.CurrentCustomer,
                    SystemCustomerAttributeNames.LanguageId,
                    languageId, _storeContext.CurrentStore.Id);

                //reset cache
                _cachedLanguage = null;
            }
        }

开始是缓存，先略过吧。LocalizationSettings在依赖注册里竟然没有。。。。断了。。