/// <summary>
/// Processes the value.
/// </summary>
/// <returns>
/// The <see cref="object" /> representing the processed value.
/// </returns>
/// <exception cref="System.NotImplementedException"></exception>
public override object ProcessValue()
{
var result = Value;
if (Value != null && !Context.PropertyDescriptor.PropertyType.IsInstanceOfType(Value))
{
// TODO: Maybe support enumerables?
using (DittoDisposableTimer.DebugDuration <TryConvertToAttribute>(string.Format("TryConvertTo ({0}, {1})", Context.Content.Id, Context.PropertyDescriptor.Name)))
{
var convert = Value.TryConvertTo(Context.PropertyDescriptor.PropertyType);
if (convert.Success)
{
result = convert.Result;
}
}
}
return(result);
}
/// <summary>
/// Processes the value.
/// </summary>
/// <returns>
/// The <see cref="object" /> representing the processed value.
/// </returns>
public override object ProcessValue()
{
var result = this.Value;
if (this.Value != null && !this.Context.PropertyDescriptor.PropertyType.IsInstanceOfType(this.Value))
{
// TODO: Maybe support enumerables?
using (DittoDisposableTimer.DebugDuration <TryConvertToAttribute>($"TryConvertTo '{this.Context.PropertyDescriptor.Name}' ({this.Context.Content.Id})"))
{
var convert = this.Value.TryConvertTo(this.Context.PropertyDescriptor.PropertyType);
if (convert.Success)
{
result = convert.Result;
}
}
}
return(result);
}
/// <summary>
/// Processes the value.
/// </summary>
/// <returns>
/// The <see cref="object" /> representing the processed value.
/// </returns>
public override object ProcessValue()
{
foreach (var processorAttr in this.Attributes)
{
using (DittoDisposableTimer.DebugDuration <DittoMultiProcessorAttribute>($"Processor '{processorAttr.GetType().Name}' ({this.Context.Content.Id})"))
{
// Get the right context type
var newCtx = this.ChainContext.ProcessorContexts.GetOrCreate(this.Context, processorAttr.ContextType);
// Populate UmbracoContext & ApplicationContext
processorAttr.UmbracoContext = this.UmbracoContext;
processorAttr.ApplicationContext = this.ApplicationContext;
// Process value
this.Value = processorAttr.ProcessValue(this.Value, newCtx, this.ChainContext);
}
}
return(this.Value);
}
/// <summary>
/// Returns an object representing the given <see cref="Type"/>.
/// </summary>
/// <param name="content">
/// The <see cref="IPublishedContent"/> to convert.
/// </param>
/// <param name="type">
/// The <see cref="Type"/> of items to return.
/// </param>
/// <param name="culture">
/// The <see cref="CultureInfo"/>
/// </param>
/// <param name="instance">
/// An existing instance of T to populate
/// </param>
/// <param name="valueResolverContexts">
/// A collection of <see cref="DittoValueResolverContext"/> entities to use whilst resolving values.
/// </param>
/// <param name="onConverting">
/// The <see cref="Action{ConversionHandlerContext}"/> to fire when converting.
/// </param>
/// <param name="onConverted">
/// The <see cref="Action{ConversionHandlerContext}"/> to fire when converted.
/// </param>
/// <returns>
/// The converted <see cref="Object"/> as the given type.
/// </returns>
public static object As(
this IPublishedContent content,
Type type,
CultureInfo culture = null,
object instance = null,
IEnumerable <DittoValueResolverContext> valueResolverContexts = null,
Action <DittoConversionHandlerContext> onConverting = null,
Action <DittoConversionHandlerContext> onConverted = null)
{
if (content == null)
{
return(null);
}
if (instance != null && !type.IsInstanceOfType(instance))
{
throw new ArgumentException(string.Format("The instance parameter does not implement Type '{0}'", type.Name), "instance");
}
using (DittoDisposableTimer.DebugDuration <object>(string.Format("IPublishedContent As ({0})", content.DocumentTypeAlias)))
{
return(ConvertContent(content, type, culture, instance, valueResolverContexts, onConverting, onConverted));
}
}
/// <summary>
/// Returns the processed value for the given type and property.
/// </summary>
/// <param name="content">The <see cref="IPublishedContent" /> to convert.</param>
/// <param name="culture">The <see cref="CultureInfo" /></param>
/// <param name="targetType">The target type.</param>
/// <param name="propertyInfo">The <see cref="PropertyInfo" /> property info associated with the type.</param>
/// <param name="instance">The instance to assign the value to.</param>
/// <param name="contextAccessor">The context accessor.</param>
/// <param name="chainContext">The <see cref="DittoChainContext"/> for the current processor chain.</param>
/// <returns>
/// The <see cref="object" /> representing the Umbraco value.
/// </returns>
private static object GetProcessedValue(
IPublishedContent content,
CultureInfo culture,
Type targetType,
PropertyInfo propertyInfo,
object instance,
IDittoContextAccessor contextAccessor,
DittoChainContext chainContext)
{
using (DittoDisposableTimer.DebugDuration <Ditto>($"Processing '{propertyInfo.Name}' ({content.Id})"))
{
// Get the target property description
var propertyDescriptor = TypeDescriptor.GetProperties(instance)[propertyInfo.Name];
// Create a base processor context for this current chain level
var baseProcessorContext = new DittoProcessorContext
{
Content = content,
TargetType = targetType,
PropertyDescriptor = propertyDescriptor,
Culture = culture
};
// Check for cache attribute
var cacheAttr = propertyInfo.GetCustomAttribute <DittoCacheAttribute>(true);
if (cacheAttr != null)
{
var ctx = new DittoCacheContext(cacheAttr, content, targetType, propertyDescriptor, culture);
return(cacheAttr.GetCacheItem(ctx, () => DoGetProcessedValue(content, propertyInfo, contextAccessor, baseProcessorContext, chainContext)));
}
else
{
return(DoGetProcessedValue(content, propertyInfo, contextAccessor, baseProcessorContext, chainContext));
}
}
}
/// <summary>
/// Set the typed value to the given instance.
/// </summary>
/// <param name="content">The <see cref="IPublishedContent"/> to convert.</param>
/// <param name="culture">The <see cref="CultureInfo"/></param>
/// <param name="propertyInfo">The <see cref="PropertyInfo"/> property info associated with the type.</param>
/// <param name="propertyValue">The property value.</param>
/// <param name="instance">The instance to assign the value to.</param>
/// <returns>The strong typed converted value for the given property.</returns>
private static object GetConvertedValue(
IPublishedContent content,
CultureInfo culture,
PropertyInfo propertyInfo,
object propertyValue,
object instance)
{
// Process the value.
object result = null;
var propertyType = propertyInfo.PropertyType;
var typeInfo = propertyType.GetTypeInfo();
// This should return false against typeof(string) etc also.
var propertyIsEnumerableType = propertyType.IsCastableEnumerableType();
// Try any custom type converters first.
// 1: Check the property.
// 2: Check any type arguments in generic enumerable types.
// 3: Check the type itself.
var converterAttribute =
propertyInfo.GetCustomAttribute <TypeConverterAttribute>()
?? (propertyIsEnumerableType ? typeInfo.GenericTypeArguments.First().GetCustomAttribute <TypeConverterAttribute>(true)
: propertyType.GetCustomAttribute <TypeConverterAttribute>(true));
if (converterAttribute != null && converterAttribute.ConverterTypeName != null)
{
// Time custom conversions.
using (DittoDisposableTimer.DebugDuration <object>(string.Format("Custom TypeConverter ({0}, {1})", content.Id, propertyInfo.Name)))
{
// Get the custom converter from the attribute and attempt to convert.
var converterType = Type.GetType(converterAttribute.ConverterTypeName);
if (converterType != null)
{
var converter = converterType.GetDependencyResolvedInstance() as TypeConverter;
if (converter != null)
{
// Create context to pass to converter implementations.
// This contains the IPublishedContent and the currently converting property descriptor.
var descriptor = TypeDescriptor.GetProperties(instance)[propertyInfo.Name];
var context = new DittoTypeConverterContext
{
ConversionType = instance.GetType(),
Instance = content,
PropertyDescriptor = descriptor
};
Type propertyValueType = null;
if (propertyValue != null)
{
propertyValueType = propertyValue.GetType();
}
// We're deliberately passing null.
// ReSharper disable once AssignNullToNotNullAttribute
if (converter.CanConvertFrom(context, propertyValueType))
{
object converted = converter.ConvertFrom(context, culture, propertyValue);
if (converted != null)
{
// Handle Typeconverters returning single objects when we want an IEnumerable.
// Use case: Someone selects a folder of images rather than a single image with the media picker.
var convertedType = converted.GetType();
if (propertyIsEnumerableType)
{
var parameterType = typeInfo.GenericTypeArguments.First();
// Some converters return an IEnumerable so we check again.
if (!convertedType.IsEnumerableType())
{
// Using 'Cast' to convert the type back to IEnumerable<T>.
object enumerablePropertyValue = EnumerableInvocations.Cast(
parameterType,
converted.YieldSingleItem());
result = enumerablePropertyValue;
}
else
{
// Nothing is strong typed anymore.
result = EnumerableInvocations.Cast(parameterType, (IEnumerable)converted);
}
}
else
{
// Return single expected items from converters returning an IEnumerable.
// Check for key/value pairs and strings.
if (convertedType.IsEnumerableType() &&
!convertedType.IsEnumerableOfKeyValueType() &&
!(convertedType == typeof(string) && propertyType == typeof(string)))
{
// Use 'FirstOrDefault' to convert the type back to T.
result = EnumerableInvocations.FirstOrDefault(
propertyType,
(IEnumerable)converted);
}
else
{
result = converted;
}
}
}
else
{
// Ensure we pass back an empty enumerable if the expected output is an enumerable.
// and null has been returned by the type converter.
if (propertyIsEnumerableType)
{
result = EnumerableInvocations.Empty(typeInfo.GenericTypeArguments.First());
}
}
}
else if (propertyType.IsInstanceOfType(propertyValue))
{
// If the TypeConverter's `CanConvertFrom` has returned false,
// then we can check if the value is the same type as the target type.
result = propertyValue;
}
}
}
}
}
else if (propertyType == typeof(HtmlString))
{
// Handle Html strings so we don't have to set the attribute.
var converterType = typeof(DittoHtmlStringConverter);
var converter = converterType.GetDependencyResolvedInstance() as TypeConverter;
if (converter != null)
{
// This contains the IPublishedContent and the currently converting property descriptor.
var descriptor = TypeDescriptor.GetProperties(instance)[propertyInfo.Name];
var context = new DittoTypeConverterContext
{
ConversionType = instance.GetType(),
Instance = content,
PropertyDescriptor = descriptor
};
Type propertyValueType = null;
if (propertyValue != null)
{
propertyValueType = propertyValue.GetType();
}
// We're deliberately passing null.
// ReSharper disable once AssignNullToNotNullAttribute
if (converter.CanConvertFrom(context, propertyValueType))
{
result = converter.ConvertFrom(context, culture, propertyValue);
}
}
}
else if (propertyType.IsInstanceOfType(propertyValue))
{
// Simple types
result = propertyValue;
}
else if (propertyValue is IPublishedContent && propertyType.IsClass)
{
// If the property value is an IPublishedContent, then we can use Ditto to map to the target type.
result = ((IPublishedContent)propertyValue).As(propertyType);
}
else if (propertyValue != null &&
propertyValue.GetType().IsEnumerableOfType(typeof(IPublishedContent)) &&
propertyType.IsEnumerable() &&
propertyType.GetEnumerableType() != null &&
propertyType.GetEnumerableType().IsClass)
{
// If the property value is IEnumerable<IPublishedContent>, then we can use Ditto to map to the target type.
result = ((IEnumerable <IPublishedContent>)propertyValue).As(propertyType.GetEnumerableType());
}
else
{
using (DittoDisposableTimer.DebugDuration <object>(string.Format("TypeConverter ({0}, {1})", content.Id, propertyInfo.Name)))
{
var convert = propertyValue.TryConvertTo(propertyType);
if (convert.Success)
{
result = convert.Result;
}
}
}
return(result);
}
/// <summary>
/// Returns the resolved value for the given type and property.
/// </summary>
/// <param name="content">The <see cref="IPublishedContent"/> to convert.</param>
/// <param name="culture">The <see cref="CultureInfo"/></param>
/// <param name="propertyInfo">The <see cref="PropertyInfo"/> property info associated with the type.</param>
/// <param name="instance">The instance to assign the value to.</param>
/// <param name="valueResolverContexts">
/// A collection of <see cref="DittoValueResolverContext"/> entities to use whilst resolving values.
/// </param>
/// <returns>The <see cref="object"/> representing the Umbraco value.</returns>
private static object GetResolvedValue(
IPublishedContent content,
CultureInfo culture,
PropertyInfo propertyInfo,
object instance,
IEnumerable <DittoValueResolverContext> valueResolverContexts = null)
{
// Check the property for an associated value attribute, otherwise fall-back on expected behaviour.
var valueAttr = propertyInfo.GetCustomAttribute <DittoValueResolverAttribute>(true);
if (valueAttr == null)
{
// Check for globally registered resolver
valueAttr = DittoValueResolverRegistry.Instance.GetRegisteredResolverAttributeFor(propertyInfo.PropertyType);
}
if (valueAttr == null)
{
// Default to umbraco property attribute
valueAttr = new UmbracoPropertyAttribute();
}
// Time custom value-resolver.
using (DittoDisposableTimer.DebugDuration <object>(string.Format("Custom ValueResolver ({0}, {1})", content.Id, propertyInfo.Name)))
{
var resolver = (DittoValueResolver)valueAttr.ResolverType.GetInstance();
DittoValueResolverContext context = null;
// Get the value from the custom attribute.
// TODO: Cache these?
var resolverTypeInstances = valueAttr.ResolverType.GetGenericTypeImplementations(typeof(DittoValueResolver <,>)).ToArray();
if (resolverTypeInstances.Length == 1)
{
var contextType = resolverTypeInstances[0].GetGenericArguments().FirstOrDefault(x => typeof(DittoValueResolverContext).IsAssignableFrom(x));
if (contextType != null)
{
var resolverContext = valueResolverContexts != null?valueResolverContexts.FirstOrDefault(x => x.GetType() == contextType) : null;
if (resolverContext != null)
{
context = resolverContext;
}
else
{
context = (DittoValueResolverContext)contextType.GetInstance();
}
}
}
// No context found so create a default one
if (context == null)
{
context = new DittoValueResolverContext();
}
// Populate internal context properties
context.ConversionType = instance.GetType();
context.Instance = content;
context.PropertyDescriptor = TypeDescriptor.GetProperties(instance)[propertyInfo.Name];
// Resolve value
return(resolver.ResolveValue(context, valueAttr, culture));
}
}
/// <summary>
/// Returns an object representing the given <see cref="Type"/>.
/// </summary>
/// <param name="content">
/// The <see cref="IPublishedContent"/> to convert.
/// </param>
/// <param name="type">
/// The <see cref="Type"/> of items to return.
/// </param>
/// <param name="culture">
/// The <see cref="CultureInfo"/>
/// </param>
/// <param name="instance">
/// An existing instance of T to populate
/// </param>
/// <param name="valueResolverContexts">
/// A collection of <see cref="DittoValueResolverContext"/> entities to use whilst resolving values.
/// </param>
/// <param name="onConverting">
/// The <see cref="Action{ConversionHandlerContext}"/> to fire when converting.
/// </param>
/// <param name="onConverted">
/// The <see cref="Action{ConversionHandlerContext}"/> to fire when converted.
/// </param>
/// <returns>
/// The converted <see cref="Object"/> as the given type.
/// </returns>
/// <exception cref="InvalidOperationException">
/// Thrown if the given type has invalid constructors.
/// </exception>
private static object ConvertContent(
IPublishedContent content,
Type type,
CultureInfo culture = null,
object instance = null,
IEnumerable <DittoValueResolverContext> valueResolverContexts = null,
Action <DittoConversionHandlerContext> onConverting = null,
Action <DittoConversionHandlerContext> onConverted = null)
{
// Check if the culture has been set, otherwise use from Umbraco, or fallback to a default
if (culture == null)
{
if (UmbracoContext.Current != null && UmbracoContext.Current.PublishedContentRequest != null)
{
culture = UmbracoContext.Current.PublishedContentRequest.Culture;
}
else
{
// Fallback
culture = CultureInfo.CurrentCulture;
}
}
// Get the default constructor, parameters and create an instance of the type.
// Try and return from the cache first. TryGetValue is faster than GetOrAdd.
ParameterInfo[] constructorParams;
ConstructorCache.TryGetValue(type, out constructorParams);
bool hasParameter = false;
if (constructorParams == null)
{
var constructor = type.GetConstructors().OrderBy(x => x.GetParameters().Length).FirstOrDefault();
if (constructor != null)
{
constructorParams = constructor.GetParameters();
ConstructorCache.TryAdd(type, constructorParams);
}
}
// If not already an instance, create an instance of the object
if (instance == null)
{
if (constructorParams != null && constructorParams.Length == 0)
{
// Internally this uses Activator.CreateInstance which is heavily optimized.
instance = type.GetInstance();
}
else if (constructorParams != null && constructorParams.Length == 1 & constructorParams[0].ParameterType == typeof(IPublishedContent))
{
// This extension method is about 7x faster than the native implementation.
instance = type.GetInstance(content);
hasParameter = true;
}
else
{
// No valid constructor, but see if the value can be cast to the type
if (type.IsInstanceOfType(content))
{
instance = content;
}
else
{
throw new InvalidOperationException(string.Format("Can't convert IPublishedContent to {0} as it has no valid constructor. A valid constructor is either an empty one, or one accepting a single IPublishedContent parameter.", type));
}
}
}
// Collect all the properties of the given type and loop through writable ones.
PropertyInfo[] virtualProperties;
PropertyInfo[] nonVirtualProperties;
VirtualPropertyCache.TryGetValue(type, out virtualProperties);
PropertyCache.TryGetValue(type, out nonVirtualProperties);
if (virtualProperties == null && nonVirtualProperties == null)
{
var properties = type.GetProperties(BindingFlags.Public | BindingFlags.Instance)
.Where(x => x.CanWrite).ToArray();
// Split out the properties.
virtualProperties = properties.Where(p => p.IsVirtualAndOverridable()).ToArray();
nonVirtualProperties = properties.Except(virtualProperties).ToArray();
VirtualPropertyCache.TryAdd(type, virtualProperties);
PropertyCache.TryAdd(type, nonVirtualProperties);
}
// A dictionary to store lazily invoked values.
var lazyProperties = new Dictionary <string, Lazy <object> >();
// If there are any virtual properties we want to lazily invoke them.
if (virtualProperties != null && virtualProperties.Any())
{
foreach (var propertyInfo in virtualProperties)
{
using (DittoDisposableTimer.DebugDuration <object>(string.Format("ForEach Virtual Property ({1} {0})", propertyInfo.Name, content.Id)))
{
// Check for the ignore attribute.
var ignoreAttr = propertyInfo.GetCustomAttribute <DittoIgnoreAttribute>();
if (ignoreAttr != null)
{
continue;
}
// Create a Lazy<object> to deferr returning our value.
var deferredPropertyInfo = propertyInfo;
var localInstance = instance;
lazyProperties.Add(
propertyInfo.Name,
new Lazy <object>(
() =>
{
// Get the value from Umbraco.
object propertyValue = GetResolvedValue(content, culture, deferredPropertyInfo, localInstance, valueResolverContexts);
return(GetConvertedValue(content, culture, deferredPropertyInfo, propertyValue, localInstance));
}));
}
}
// Create a proxy instance to replace our object.
var interceptor = new LazyInterceptor(instance, lazyProperties);
var factory = new ProxyFactory();
instance = hasParameter
? factory.CreateProxy(type, interceptor, content)
: factory.CreateProxy(type, interceptor);
}
// We have the instance object but haven't yet populated properties
// so fire the on converting event handlers
OnConverting(content, type, instance, onConverting);
// Now loop through and convert non-virtual properties.
if (nonVirtualProperties != null && nonVirtualProperties.Any())
{
foreach (var propertyInfo in nonVirtualProperties)
{
using (DittoDisposableTimer.DebugDuration <object>(string.Format("ForEach Property ({1} {0})", propertyInfo.Name, content.Id)))
{
// Check for the ignore attribute.
var ignoreAttr = propertyInfo.GetCustomAttribute <DittoIgnoreAttribute>();
if (ignoreAttr != null)
{
continue;
}
// Set the value normally.
// ReSharper disable once PossibleMultipleEnumeration
object propertyValue = GetResolvedValue(content, culture, propertyInfo, instance, valueResolverContexts);
object result = GetConvertedValue(content, culture, propertyInfo, propertyValue, instance);
propertyInfo.SetValue(instance, result, null);
}
}
}
// We have now finished populating the instance object so go ahead
// and fire the on converted event handlers
OnConverted(content, type, instance, onConverted);
return(instance);
}
/// <summary>
/// Returns the processed value for the given type and property.
/// </summary>
/// <param name="content">The content.</param>
/// <param name="propertyInfo">The property information.</param>
/// <param name="contextAccessor">The context accessor.</param>
/// <param name="baseProcessorContext">The base processor context.</param>
/// <param name="chainContext">The <see cref="DittoChainContext"/> for the current processor chain.</param>
/// <returns>Returns the processed value.</returns>
private static object DoGetProcessedValue(
IPublishedContent content,
PropertyInfo propertyInfo,
IDittoContextAccessor contextAccessor,
DittoProcessorContext baseProcessorContext,
DittoChainContext chainContext)
{
// Check the property for any explicit processor attributes
var processorAttrs = propertyInfo.GetCustomAttributes <DittoProcessorAttribute>(true)
.OrderBy(x => x.Order)
.ToList();
if (!processorAttrs.Any())
{
// Adds the default processor for this conversion
processorAttrs.Add(DittoProcessorRegistry.Instance.GetDefaultProcessorFor(baseProcessorContext.TargetType));
}
var propertyType = propertyInfo.PropertyType;
// Check for type registered processors
processorAttrs.AddRange(propertyType
.GetCustomAttributes <DittoProcessorAttribute>(true)
.OrderBy(x => x.Order));
// Check any type arguments in generic enumerable types.
// This should return false against typeof(string) etc also.
var typeInfo = propertyType.GetTypeInfo();
bool isEnumerable = false;
Type typeArg = null;
if (propertyType.IsCastableEnumerableType())
{
typeArg = typeInfo.GenericTypeArguments.First();
processorAttrs.AddRange(typeInfo
.GenericTypeArguments
.First()
.GetCustomAttributes <DittoProcessorAttribute>(true)
.OrderBy(x => x.Order)
.ToList());
isEnumerable = true;
}
// Check for globally registered processors
processorAttrs.AddRange(DittoProcessorRegistry.Instance.GetRegisteredProcessorAttributesFor(propertyInfo.PropertyType));
// Add any core processors onto the end
processorAttrs.AddRange(DittoProcessorRegistry.Instance.GetPostProcessorAttributes());
// Create holder for value as it's processed
object currentValue = content;
// Process attributes
foreach (var processorAttr in processorAttrs)
{
using (DittoDisposableTimer.DebugDuration <Ditto>($"Processor '{processorAttr.GetType().Name}' ({content.Id})"))
{
// Get the right context type
var ctx = chainContext.ProcessorContexts.GetOrCreate(baseProcessorContext, processorAttr.ContextType);
// Populate UmbracoContext & ApplicationContext
processorAttr.UmbracoContext = contextAccessor.UmbracoContext;
processorAttr.ApplicationContext = contextAccessor.ApplicationContext;
// Process value
currentValue = processorAttr.ProcessValue(currentValue, ctx, chainContext);
}
}
// The following has to happen after all the processors.
if (isEnumerable && currentValue != null && currentValue.Equals(Enumerable.Empty <object>()))
{
if (propertyType.IsInterface)
{
// You cannot set an enumerable of type from an empty object array.
currentValue = EnumerableInvocations.Cast(typeArg, (IEnumerable)currentValue);
}
else
{
// This should allow the casting back of IEnumerable<T> to an empty List<T> Collection<T> etc.
// I cant think of any that don't have an empty constructor
currentValue = propertyType.GetInstance();
}
}
return((currentValue == null && propertyType.IsValueType)
? propertyInfo.PropertyType.GetInstance() // Set to default instance of value type
: currentValue);
}
/// <summary>
/// Returns an object representing the given <see cref="Type"/>.
/// </summary>
/// <param name="content">
/// The <see cref="IPublishedContent"/> to convert.
/// </param>
/// <param name="type">
/// The <see cref="Type"/> of items to return.
/// </param>
/// <param name="contextAccessor">
/// The context accessor.
/// </param>
/// <param name="culture">
/// The <see cref="CultureInfo"/>
/// </param>
/// <param name="instance">
/// An existing instance of T to populate
/// </param>
/// <param name="onConverting">
/// The <see cref="Action{ConversionHandlerContext}"/> to fire when converting.
/// </param>
/// <param name="onConverted">
/// The <see cref="Action{ConversionHandlerContext}"/> to fire when converted.
/// </param>
/// <param name="chainContext">
/// The <see cref="DittoChainContext"/> for the current processor chain.
/// </param>
/// <returns>
/// The converted <see cref="Object"/> as the given type.
/// </returns>
/// <exception cref="InvalidOperationException">
/// Thrown if the given type has invalid constructors.
/// </exception>
private static object ConvertContent(
IPublishedContent content,
Type type,
IDittoContextAccessor contextAccessor,
CultureInfo culture,
object instance,
Action <DittoConversionHandlerContext> onConverting,
Action <DittoConversionHandlerContext> onConverted,
DittoChainContext chainContext)
{
// Collect all the properties of the given type and loop through writable ones.
PropertyInfo[] properties;
PropertyCache.TryGetValue(type, out properties);
if (properties == null)
{
properties = type.GetProperties(BindingFlags.Public | BindingFlags.Instance)
.Where(x => x.CanWrite && x.GetSetMethod() != null).ToArray();
PropertyCache.TryAdd(type, properties);
}
// Check the validity of the mpped type constructor as early as possible.
ParameterInfo[] constructorParams = type.GetConstructorParameters();
bool validConstructor = false;
bool hasParameter = false;
bool isType = false;
bool hasLazy = false;
if (constructorParams != null)
{
// Is it PublishedContentmModel or similar?
if (constructorParams.Length == 1 && constructorParams[0].ParameterType == typeof(IPublishedContent))
{
hasParameter = true;
}
if (constructorParams.Length == 0 || hasParameter)
{
validConstructor = true;
}
}
// No valid constructor, but see if the value can be cast to the type
if (type.IsInstanceOfType(content))
{
isType = true;
validConstructor = true;
}
if (!validConstructor)
{
throw new InvalidOperationException(
$"Cannot convert IPublishedContent to {type} as it has no valid constructor. " +
"A valid constructor is either an empty one, or one accepting a single IPublishedContent parameter.");
}
PropertyInfo[] lazyProperties = null;
// If not already an instance, create an instance of the object
if (instance == null)
{
// We can only proxy new instances.
lazyProperties = properties.Where(x => x.ShouldAttemptLazyLoad()).ToArray();
if (lazyProperties.Any())
{
hasLazy = true;
var factory = new ProxyFactory();
instance = hasParameter
? factory.CreateProxy(type, lazyProperties.Select(x => x.Name), content)
: factory.CreateProxy(type, lazyProperties.Select(x => x.Name));
}
else if (isType)
{
instance = content;
}
else
{
// 1: This extension method is about 7x faster than the native implementation.
// 2: Internally this uses Activator.CreateInstance which is heavily optimized.
instance = hasParameter
? type.GetInstance(content) // 1
: type.GetInstance(); // 2
}
}
// We have the instance object but haven't yet populated properties
// so fire the on converting event handlers
OnConverting(content, type, culture, instance, onConverting);
if (hasLazy)
{
// A dictionary to store lazily invoked values.
var lazyMappings = new Dictionary <string, Lazy <object> >();
foreach (var propertyInfo in lazyProperties)
{
// Configure lazy properties
using (DittoDisposableTimer.DebugDuration <Ditto>($"Lazy Property ({content.Id} {propertyInfo.Name})"))
{
// Ensure it's a virtual property (Only relevant to property level lazy loads)
if (!propertyInfo.IsVirtualAndOverridable())
{
throw new InvalidOperationException($"Lazy property '{propertyInfo.Name}' of type '{type.AssemblyQualifiedName}' must be declared virtual in order to be lazy loadable.");
}
lazyMappings.Add(propertyInfo.Name, new Lazy <object>(() => GetProcessedValue(content, culture, type, propertyInfo, instance, contextAccessor, chainContext)));
}
}
((IProxy)instance).Interceptor = new LazyInterceptor(lazyMappings);
}
// Process any non lazy properties
foreach (var propertyInfo in properties.Where(x => !x.ShouldAttemptLazyLoad()))
{
// Check for the ignore attribute.
if (propertyInfo.HasCustomAttribute <DittoIgnoreAttribute>())
{
continue;
}
// Set the value normally.
var value = GetProcessedValue(content, culture, type, propertyInfo, instance, contextAccessor, chainContext);
// This over 4x faster as propertyInfo.SetValue(instance, value, null);
FastPropertyAccessor.SetValue(propertyInfo, instance, value);
}
// We have now finished populating the instance object so go ahead
// and fire the on converted event handlers
OnConverted(content, type, culture, instance, onConverted);
return(instance);
}
