/// <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);
}
/// <summary>Returns an object representing the given <see cref="Type"/>.</summary>
/// <param name="content">The <see cref="IPublishedContent"/> to convert.</param>
/// <param name="config">The Ditto configuration for the type.</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,
DittoTypeInfo config,
CultureInfo culture,
object instance,
Action <DittoConversionHandlerContext> onConverting,
Action <DittoConversionHandlerContext> onConverted,
DittoChainContext chainContext)
{
// If not already an instance, create an instance of the object.
if (instance == null)
{
// Check the validity of the mapped type constructor.
if (config.ConstructorIsValid == false)
{
throw new InvalidOperationException(
$"Cannot convert IPublishedContent to {config.TargetType} as it has no valid constructor. " +
"A valid constructor is either empty, or one accepting a single IPublishedContent parameter.");
}
// We can only proxy new instances.
if (config.ConstructorRequiresProxyType)
{
var factory = new ProxyFactory();
instance = config.ConstructorHasPublishedContentParameter
? factory.CreateProxy(config.TargetType, config.LazyPropertyNames, content)
: factory.CreateProxy(config.TargetType, config.LazyPropertyNames);
}
else if (config.IsOfTypePublishedContent)
{
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 = config.ConstructorHasPublishedContentParameter
// TODO: Review this, as we could get the Constructor metadata from the "type-cache"?
? config.TargetType.GetInstance(content) // 1
: config.TargetType.GetInstance(); // 2
}
}
// We have the instance object but haven't yet populated properties
// so fire the on converting event handlers
OnConverting(content, config, culture, instance, onConverting);
if (config.HasLazyProperties)
{
// A dictionary to store lazily invoked values.
var lazyMappings = new Dictionary <string, Lazy <object> >();
foreach (var lazyProperty in config.LazyProperties)
{
// Configure lazy properties
lazyMappings.Add(lazyProperty.PropertyInfo.Name, new Lazy <object>(() => GetProcessedValue(content, culture, config, lazyProperty, instance, chainContext)));
}
((IProxy)instance).Interceptor = new LazyInterceptor(lazyMappings);
}
// Process any eager properties
if (config.HasEagerProperties)
{
foreach (var eagerProperty in config.EagerProperties)
{
// Set the value normally.
var value = GetProcessedValue(content, culture, config, eagerProperty, instance, chainContext);
// This over 4x faster as propertyInfo.SetValue(instance, value, null);
FastPropertyAccessor.SetValue(eagerProperty.PropertyInfo, instance, value);
}
}
// We have now finished populating the instance object so go ahead
// and fire the on converted event handlers
OnConverted(content, config, culture, instance, onConverted);
return(instance);
}
