/// <summary>
/// Creates a new <see cref="ModelBindingContext"/> for top-level model binding operation.
/// </summary>
/// <param name="operationBindingContext">
/// The <see cref="OperationBindingContext"/> associated with the binding operation.
/// </param>
/// <param name="metadata"><see cref="ModelMetadata"/> associated with the model.</param>
/// <param name="bindingInfo"><see cref="BindingInfo"/> associated with the model.</param>
/// <param name="modelName">The name of the property or parameter being bound.</param>
/// <returns>A new instance of <see cref="ModelBindingContext"/>.</returns>
public static ModelBindingContext CreateBindingContext(
[NotNull] OperationBindingContext operationBindingContext,
[NotNull] ModelStateDictionary modelState,
[NotNull] ModelMetadata metadata,
BindingInfo bindingInfo,
[NotNull] string modelName)
{
var binderModelName = bindingInfo?.BinderModelName ?? metadata.BinderModelName;
var propertyPredicateProvider =
bindingInfo?.PropertyBindingPredicateProvider ?? metadata.PropertyBindingPredicateProvider;
return new ModelBindingContext()
{
BinderModelName = binderModelName,
BindingSource = bindingInfo?.BindingSource ?? metadata.BindingSource,
BinderType = bindingInfo?.BinderType ?? metadata.BinderType,
PropertyFilter = propertyPredicateProvider?.PropertyFilter,
// We only support fallback to empty prefix in cases where the model name is inferred from
// the parameter or property being bound.
FallbackToEmptyPrefix = binderModelName == null,
// Because this is the top-level context, FieldName and ModelName should be the same.
FieldName = binderModelName ?? modelName,
ModelName = binderModelName ?? modelName,
IsTopLevelObject = true,
ModelMetadata = metadata,
ModelState = modelState,
OperationBindingContext = operationBindingContext,
ValueProvider = operationBindingContext.ValueProvider,
ValidationState = new ValidationStateDictionary(),
};
}
/// <summary>
/// Creates a copy of a <see cref="BindingInfo"/>.
/// </summary>
/// <param name="other">The <see cref="BindingInfo"/> to copy.</param>
public BindingInfo(BindingInfo other)
{
if (other == null)
{
throw new ArgumentNullException(nameof(other));
}
BindingSource = other.BindingSource;
BinderModelName = other.BinderModelName;
BinderType = other.BinderType;
PropertyBindingPredicateProvider = other.PropertyBindingPredicateProvider;
}
/// <inheritdocs />
public async Task<IDictionary<string, object>> BindArgumentsAsync(WidgetContext context, MethodInfo method, IDictionary<string, object> values)
{
var bindingContext = new OperationBindingContext
{
HttpContext = context.ViewContext.HttpContext,
InputFormatters = _options.InputFormatters,
MetadataProvider = _modelMetadataProvider,
ModelBinder = new CompositeModelBinder(_options.ModelBinders),
ValidatorProvider = new CompositeModelValidatorProvider(_options.ModelValidatorProviders),
ValueProvider = await CompositeValueProvider.CreateAsync(_options.ValueProviderFactories, new ValueProviderFactoryContext(context.ViewContext.HttpContext, context.ViewContext.RouteData.Values))
};
var arguments = new Dictionary<string, object>(StringComparer.Ordinal);
var parameters = method.GetParameters();
foreach (var parameter in parameters)
{
if (values.ContainsKey(parameter.Name))
{
arguments.Add(parameter.Name, values[parameter.Name]);
}
else
{
var attribute = parameter.GetCustomAttributes().OfType<IBindingSourceMetadata>().FirstOrDefault();
var bindingInfo = new BindingInfo()
{
BindingSource = attribute?.BindingSource
};
var metadata = _modelMetadataProvider.GetMetadataForType(parameter.ParameterType);
var modelBindingContext = ModelBindingContext.CreateBindingContext(
bindingContext,
context.ModelState,
metadata,
bindingInfo,
parameter.Name);
var result = await bindingContext.ModelBinder.BindModelAsync(modelBindingContext);
if (result.IsModelSet)
{
_objectModelValidator.Validate(bindingContext.ValidatorProvider, context.ModelState, modelBindingContext.ValidationState, result.Key, result.Model);
arguments.Add(parameter.Name, result.Model);
}
else
{
arguments.Add(parameter.Name, Activator.CreateInstance(parameter.ParameterType));
}
}
}
return arguments;
}
/// <summary>
/// Constructs a new instance of <see cref="BindingInfo"/> from the given <paramref name="attributes"/>.
/// </summary>
/// <param name="attributes">A collection of attributes which are used to construct <see cref="BindingInfo"/>
/// </param>
/// <returns>A new instance of <see cref="BindingInfo"/>.</returns>
public static BindingInfo GetBindingInfo(IEnumerable<object> attributes)
{
var bindingInfo = new BindingInfo();
var isBindingInfoPresent = false;
// BinderModelName
foreach (var binderModelNameAttribute in attributes.OfType<IModelNameProvider>())
{
isBindingInfoPresent = true;
if (binderModelNameAttribute?.Name != null)
{
bindingInfo.BinderModelName = binderModelNameAttribute.Name;
break;
}
}
// BinderType
foreach (var binderTypeAttribute in attributes.OfType<IBinderTypeProviderMetadata>())
{
isBindingInfoPresent = true;
if (binderTypeAttribute.BinderType != null)
{
bindingInfo.BinderType = binderTypeAttribute.BinderType;
break;
}
}
// BindingSource
foreach (var bindingSourceAttribute in attributes.OfType<IBindingSourceMetadata>())
{
isBindingInfoPresent = true;
if (bindingSourceAttribute.BindingSource != null)
{
bindingInfo.BindingSource = bindingSourceAttribute.BindingSource;
break;
}
}
// PropertyBindingPredicateProvider
var predicateProviders = attributes.OfType<IPropertyBindingPredicateProvider>().ToArray();
if (predicateProviders.Length > 0)
{
isBindingInfoPresent = true;
bindingInfo.PropertyBindingPredicateProvider = new CompositePredicateProvider(
predicateProviders);
}
return isBindingInfoPresent ? bindingInfo : null;
}
/// <summary>
/// Constructs a new instance of <see cref="ModelBindingContext"/> from given <paramref name="metadata"/>
/// and <paramref name="bindingInfo"/>.
/// </summary>
/// <param name="metadata"><see cref="ModelMetadata"/> associated with the model.</param>
/// <param name="bindingInfo"><see cref="BindingInfo"/> associated with the model.</param>
/// <param name="modelName">An optional name of the model to be used.</param>
/// <returns>A new instance of <see cref="ModelBindingContext"/>.</returns>
public static ModelBindingContext GetModelBindingContext(
[NotNull] ModelMetadata metadata,
BindingInfo bindingInfo,
string modelName)
{
var binderModelName = bindingInfo?.BinderModelName ?? metadata.BinderModelName;
var propertyPredicateProvider =
bindingInfo?.PropertyBindingPredicateProvider ?? metadata.PropertyBindingPredicateProvider;
return new ModelBindingContext
{
ModelMetadata = metadata,
BindingSource = bindingInfo?.BindingSource ?? metadata.BindingSource,
PropertyFilter = propertyPredicateProvider?.PropertyFilter,
BinderType = bindingInfo?.BinderType ?? metadata.BinderType,
BinderModelName = binderModelName,
ModelName = binderModelName ?? metadata.PropertyName ?? modelName,
FallbackToEmptyPrefix = binderModelName == null,
};
}
private static ModelBindingContext GetModelBindingContext(
string parameterName,
ModelMetadata metadata,
BindingInfo bindingInfo,
ModelStateDictionary modelState,
OperationBindingContext operationBindingContext)
{
var modelBindingContext = ModelBindingContext.GetModelBindingContext(
metadata,
bindingInfo,
parameterName);
modelBindingContext.ModelState = modelState;
modelBindingContext.ValueProvider = operationBindingContext.ValueProvider;
modelBindingContext.OperationBindingContext = operationBindingContext;
return modelBindingContext;
}