protected void SetupValidator(ModelMetadata metadata)
{
var fieldId = $"{metadata.ContainerType.FullName}.{metadata.PropertyName}".ToLowerInvariant();
AttributeFullId = $"{Attribute.TypeId}.{fieldId}".ToLowerInvariant();
AttributeWeakId = $"{typeof(T).FullName}.{fieldId}".ToLowerInvariant();
var item = ProcessStorage <string, CacheItem> .GetOrAdd(AttributeFullId, _ => // map cache is based on static dictionary, set-up once for entire application instance
{ // (by design, no reason to recompile once compiled expressions)
IDictionary <string, Expression> fields = null;
Attribute.Compile(metadata.ContainerType, parser =>
{
fields = parser.GetFields();
FieldsMap = fields.ToDictionary(x => x.Key, x => Helper.GetCoarseType(x.Value.Type));
ConstsMap = parser.GetConsts();
EnumsMap = parser.GetEnums();
MethodsList = parser.GetMethods();
}); // compile the expression associated with attribute (to be cached for subsequent invocations)
AssertClientSideCompatibility();
ParsersMap = fields
.Select(kvp => new
{
FullName = kvp.Key,
ParserAttribute = (kvp.Value as MemberExpression)?.Member.GetAttributes <ValueParserAttribute>().SingleOrDefault()
}).Where(x => x.ParserAttribute != null)
.ToDictionary(x => x.FullName, x => x.ParserAttribute.ParserName);
if (!ParsersMap.ContainsKey(metadata.PropertyName))
{
var currentField = metadata.ContainerType
.GetProperties().Single(p => metadata.PropertyName == p.Name);
var valueParser = currentField.GetAttributes <ValueParserAttribute>().SingleOrDefault();
if (valueParser != null)
{
ParsersMap.Add(new KeyValuePair <string, string>(metadata.PropertyName, valueParser.ParserName));
}
}
return(new CacheItem
{
FieldsMap = FieldsMap,
ConstsMap = ConstsMap,
EnumsMap = EnumsMap,
MethodsList = MethodsList,
ParsersMap = ParsersMap
});
});
FieldsMap = item.FieldsMap;
ConstsMap = item.ConstsMap;
EnumsMap = item.EnumsMap;
MethodsList = item.MethodsList;
ParsersMap = item.ParsersMap;
}
/// <summary>
/// Generates client validation rule with the basic set of parameters.
/// </summary>
/// <param name="type">The validation type.</param>
/// <returns>
/// Client validation rule with the basic set of parameters.
/// </returns>
/// <exception cref="System.ComponentModel.DataAnnotations.ValidationException"></exception>
protected ModelClientValidationRule GetBasicRule(string type)
{
try
{
var rule = new ModelClientValidationRule
{
ErrorMessage = FormattedErrorMessage,
ValidationType = ProvideUniqueValidationType(type)
};
rule.ValidationParameters.Add("expression", Expression.ToJson());
Debug.Assert(FieldsMap != null);
if (FieldsMap.Any())
{
rule.ValidationParameters.Add("fieldsmap", FieldsMap.ToJson());
}
Debug.Assert(ConstsMap != null);
if (ConstsMap.Any())
{
rule.ValidationParameters.Add("constsmap", ConstsMap.ToJson());
}
Debug.Assert(EnumsMap != null);
if (EnumsMap.Any())
{
rule.ValidationParameters.Add("enumsmap", EnumsMap.ToJson());
}
Debug.Assert(MethodsList != null);
if (MethodsList.Any())
{
rule.ValidationParameters.Add("methodslist", MethodsList.ToJson());
}
Debug.Assert(ParsersMap != null);
if (ParsersMap.Any())
{
rule.ValidationParameters.Add("parsersmap", ParsersMap.ToJson());
}
Debug.Assert(ErrFieldsMap != null);
if (ErrFieldsMap.Any())
{
rule.ValidationParameters.Add("errfieldsmap", ErrFieldsMap.ToJson());
}
return(rule);
}
catch (Exception e)
{
throw new ValidationException(
$"{GetType().Name}: collecting of client validation rules for {FieldName} field failed.", e);
}
}
/// <summary>
/// Retrieves a collection of client validation rules (which are next sent to browsers).
/// </summary>
/// <returns>
/// A collection of client validation rules.
/// </returns>
public override IEnumerable <ModelClientValidationRule> GetClientValidationRules()
{
var rule = new ModelClientValidationRule
{
ErrorMessage = FormattedErrorMessage,
ValidationType = ProvideUniqueValidationType("assertthat")
};
rule.ValidationParameters.Add("expression", Expression);
rule.ValidationParameters.Add("fieldsmap", FieldsMap.ToJson());
rule.ValidationParameters.Add("constsmap", ConstsMap.ToJson());
rule.ValidationParameters.Add("parsersmap", ParsersMap.ToJson());
yield return(rule);
}
/// <summary>
/// Attaches client validation rule to the context.
/// </summary>
/// <param name="context">The Client Model Validation Context.</param>
/// <param name="type">The validation type.</param>
/// <param name="defaultErrorMessage">The default Error Message.</param>
/// <returns>
/// void
/// </returns>
/// <exception cref="System.ComponentModel.DataAnnotations.ValidationException"></exception>
protected void AttachValidationRules(ClientModelValidationContext context, string type, string defaultErrorMessage)
{
var errorMessage = !string.IsNullOrEmpty(FormattedErrorMessage) ? FormattedErrorMessage : defaultErrorMessage;
var uniqueValidationType = ProvideUniqueValidationType(type);
try
{
MergeAttribute(context.Attributes, "data-val", "true");
MergeAttribute(context.Attributes, $"data-val-{uniqueValidationType}", errorMessage);
MergeAttribute(context.Attributes, $"data-val-{uniqueValidationType}-expression", Expression.ToJson());
Debug.Assert(FieldsMap != null);
if (FieldsMap.Any())
{
MergeAttribute(context.Attributes, $"data-val-{uniqueValidationType}-fieldsmap", FieldsMap.ToJson());
}
Debug.Assert(ConstsMap != null);
if (ConstsMap.Any())
{
MergeAttribute(context.Attributes, $"data-val-{uniqueValidationType}-constsmap", ConstsMap.ToJson());
}
Debug.Assert(EnumsMap != null);
if (EnumsMap.Any())
{
MergeAttribute(context.Attributes, $"data-val-{uniqueValidationType}-enumsmap", EnumsMap.ToJson());
}
Debug.Assert(MethodsList != null);
if (MethodsList.Any())
{
MergeAttribute(context.Attributes, $"data-val-{uniqueValidationType}-methodslist", MethodsList.ToJson());
}
Debug.Assert(ParsersMap != null);
if (ParsersMap.Any())
{
MergeAttribute(context.Attributes, $"data-val-{uniqueValidationType}-parsersmap", ParsersMap.ToJson());
}
Debug.Assert(ErrFieldsMap != null);
if (ErrFieldsMap.Any())
{
MergeAttribute(context.Attributes, $"data-val-{uniqueValidationType}-errfieldsmap", ErrFieldsMap.ToJson());
}
}
catch (Exception e)
{
throw new ValidationException(
$"{GetType().Name}: collecting of client validation rules for {FieldName} field failed.", e);
}
}
public override void AddValidation(ClientModelValidationContext context)
{
SetupValidator(context.ModelMetadata);
var validationId = GetUniqueValidationId(context);
var formattedErrorMessage = GetErrorMessage(context);
MergeAttribute(context.Attributes, "data-val", "true");
MergeAttribute(context.Attributes, $"data-val-{validationId}", formattedErrorMessage);
MergeExpressiveAttribute(context, validationId, "expression", Attribute.Expression);
if (AllowEmpty.HasValue)
{
MergeExpressiveAttribute(context, validationId, "allowempty", AllowEmpty);
}
if (FieldsMap != null && FieldsMap.Any())
{
MergeExpressiveAttribute(context, validationId, "fieldsmap", FieldsMap);
}
if (ConstsMap != null && ConstsMap.Any())
{
MergeExpressiveAttribute(context, validationId, "constsmap", ConstsMap);
}
if (EnumsMap != null && EnumsMap.Any())
{
MergeExpressiveAttribute(context, validationId, "enumsmap", EnumsMap);
}
if (MethodsList != null && MethodsList.Any())
{
MergeExpressiveAttribute(context, validationId, "methodslist", MethodsList);
}
if (ParsersMap != null && ParsersMap.Any())
{
MergeExpressiveAttribute(context, validationId, "parsersmap", ParsersMap);
}
if (ErrFieldsMap != null && ErrFieldsMap.Any())
{
MergeExpressiveAttribute(context, validationId, "errfieldsmap", ErrFieldsMap);
}
}
/// <summary>
/// Constructor for expressive model validator.
/// </summary>
/// <param name="metadata">The model metadata.</param>
/// <param name="attribute">The expressive attribute instance.</param>
/// <param name="processCache">An IMemoryCache instance, scoped to the process.</param>
/// <param name="requestCache">A RequestCache instance, scoped to the request.</param>
/// <exception cref="System.ComponentModel.DataAnnotations.ValidationException"></exception>
protected ExpressiveValidator(ModelMetadata metadata, T attribute, IMemoryCache processCache, IMemoryCache requestCache)
{
_requestCache = requestCache;
try
{
Debug.WriteLine($"[ctor entry] process: {Process.GetCurrentProcess().Id}, thread: {Thread.CurrentThread.ManagedThreadId}");
var fieldId = $"{metadata.ContainerType.FullName}.{metadata.PropertyName}".ToLowerInvariant();
AttributeFullId = $"{attribute.TypeId}.{fieldId}".ToLowerInvariant();
AttributeWeakId = $"{typeof(T).FullName}.{fieldId}".ToLowerInvariant();
FieldName = metadata.PropertyName;
// Parsing the attributes and constructing the maps can be quite expensive. They only need to be parsed once for the
// application, so the results of this parsing are stored in a cache scoped to the process.
//
// Note that, unlike the implementation in the original Expressive Annotations (which used Lazy<T> and a ConcurrentDictionary),
// this use of IMemoryCache for caching the data about parsed attributes doesn't guarantee that the cache entries will only
// be added once. If a second concurrent request triggers parsing of a set of attributes before the first request has completed,
// one of them will end up overwriting the cache entries of the other, so parsing will happen twice. (Or more times, if there
// are multiple requests). But once one cache entry has been added, subsequent requests for the same attribute will get the
// parsing results from the cache.
//
// Unless the attributes are extremely numerous, complex and slow to parse, causing performance problems the first time the
// application is used after starting, this shouldn't really be a problem.
//
// Good discussion about similar issues here:
// https://www.hanselman.com/blog/EyesWideOpenCorrectCachingIsAlwaysHard.aspx
var item = processCache.GetOrCreate(AttributeFullId, entry =>
{
Debug.WriteLine($"[cache add] process: {Process.GetCurrentProcess().Id}, thread: {Thread.CurrentThread.ManagedThreadId}");
entry.SetPriority(CacheItemPriority.NeverRemove);
IDictionary <string, Expression> fields = null;
attribute.Compile(metadata.ContainerType, parser =>
{
fields = parser.GetFields();
FieldsMap = fields.ToDictionary(x => x.Key, x => Helper.GetCoarseType(x.Value.Type));
ConstsMap = parser.GetConsts();
EnumsMap = parser.GetEnums();
MethodsList = parser.GetMethods();
}); // compile the expression associated with attribute (to be cached for subsequent invocations)
AssertClientSideCompatibility();
ParsersMap = fields
.Select(kvp => new
{
FullName = kvp.Key,
ParserAttribute = (kvp.Value as MemberExpression)?.Member.GetAttributes <ValueParserAttribute>().SingleOrDefault()
}).Where(x => x.ParserAttribute != null)
.ToDictionary(x => x.FullName, x => x.ParserAttribute.ParserName);
if (!ParsersMap.ContainsKey(metadata.PropertyName))
{
var currentField = metadata.ContainerType
.GetProperties().Single(p => metadata.PropertyName == p.Name);
var valueParser = currentField.GetAttributes <ValueParserAttribute>().SingleOrDefault();
if (valueParser != null)
{
ParsersMap.Add(new KeyValuePair <string, string>(metadata.PropertyName, valueParser.ParserName));
}
}
return(new ProcessCacheItem
{
FieldsMap = FieldsMap,
ConstsMap = ConstsMap,
EnumsMap = EnumsMap,
MethodsList = MethodsList,
ParsersMap = ParsersMap
});
});
FieldsMap = item.FieldsMap;
ConstsMap = item.ConstsMap;
EnumsMap = item.EnumsMap;
MethodsList = item.MethodsList;
ParsersMap = item.ParsersMap;
Expression = attribute.Expression;
IDictionary <string, Guid> errFieldsMap;
FormattedErrorMessage = attribute.FormatErrorMessage(metadata.GetDisplayName(), attribute.Expression, metadata.ContainerType, out errFieldsMap); // fields names, in contrast to values, do not change in runtime, so will be provided in message (less code in js)
ErrFieldsMap = errFieldsMap;
}
catch (Exception e)
{
throw new ValidationException(
$"{GetType().Name}: validation applied to {metadata.PropertyName} field failed.", e);
}
}
/// <summary>
/// Constructor for expressive model validator.
/// </summary>
/// <param name="metadata">The model metadata instance.</param>
/// <param name="context">The controller context instance.</param>
/// <param name="attribute">The expressive attribute instance.</param>
/// <exception cref="System.ComponentModel.DataAnnotations.ValidationException"></exception>
protected ExpressiveValidator(ModelMetadata metadata, ControllerContext context, T attribute)
: base(metadata, context, attribute)
{
try
{
Debug.WriteLine($"[ctor entry] process: {Process.GetCurrentProcess().Id}, thread: {Thread.CurrentThread.ManagedThreadId}");
var fieldId = $"{metadata.ContainerType.FullName}.{metadata.PropertyName}".ToLowerInvariant();
AttributeFullId = $"{attribute.TypeId}.{fieldId}".ToLowerInvariant();
AttributeWeakId = $"{typeof (T).FullName}.{fieldId}".ToLowerInvariant();
FieldName = metadata.PropertyName;
ResetSuffixAllocation();
var item = MapCache <string, CacheItem> .GetOrAdd(AttributeFullId, _ => // map cache is based on static dictionary, set-up once for entire application instance
{ // (by design, no reason to recompile once compiled expressions)
Debug.WriteLine($"[cache add] process: {Process.GetCurrentProcess().Id}, thread: {Thread.CurrentThread.ManagedThreadId}");
var parser = new Parser();
parser.RegisterToolchain();
parser.Parse <bool>(metadata.ContainerType, attribute.Expression);
var fields = parser.GetFields();
FieldsMap = fields.ToDictionary(x => x.Key, x => Helper.GetCoarseType(x.Value.Type));
ConstsMap = parser.GetConsts();
ParsersMap = fields
.Select(kvp => new
{
FullName = kvp.Key,
ParserAttribute = ((MemberExpression)kvp.Value).Member.GetAttributes <ValueParserAttribute>().SingleOrDefault()
}).Where(x => x.ParserAttribute != null)
.ToDictionary(x => x.FullName, x => x.ParserAttribute.ParserName);
if (!ParsersMap.ContainsKey(metadata.PropertyName))
{
var currentField = metadata.ContainerType
.GetProperties().Single(p => metadata.PropertyName == p.Name);
var valueParser = currentField.GetAttributes <ValueParserAttribute>().SingleOrDefault();
if (valueParser != null)
{
ParsersMap.Add(new KeyValuePair <string, string>(metadata.PropertyName, valueParser.ParserName));
}
}
AssertNoNamingCollisionsAtCorrespondingSegments();
attribute.Compile(metadata.ContainerType); // compile expressions in attributes (to be cached for subsequent invocations)
return(new CacheItem
{
FieldsMap = FieldsMap,
ConstsMap = ConstsMap,
ParsersMap = ParsersMap
});
});
FieldsMap = item.FieldsMap;
ConstsMap = item.ConstsMap;
ParsersMap = item.ParsersMap;
Expression = attribute.Expression;
IDictionary <string, Guid> errFieldsMap;
FormattedErrorMessage = attribute.FormatErrorMessage(metadata.GetDisplayName(), attribute.Expression, metadata.ContainerType, out errFieldsMap); // fields names, in contrast to values, do not change in runtime, so will be provided in message (less code in js)
ErrFieldsMap = errFieldsMap;
}
catch (Exception e)
{
throw new ValidationException(
$"{GetType().Name}: validation applied to {metadata.PropertyName} field failed.", e);
}
}
