public bool KeyMatches(object providedKeyInstance)
{
// Check if this rule has been turned off by a previous parse attempt
if (_couldNotParseKeyType || _couldNotParseParameterValue || providedKeyInstance == null)
{
return(false);
}
var providedKeyType = providedKeyInstance.GetType();
var keyType = providedKeyType;
if (_couldNotParseExpressionAgainstTypes.Contains(keyType))
{
return(false);
}
var declaredKeyType = Type.GetType(ForKeyType, false, true);
if (declaredKeyType == null)
{
_couldNotParseKeyType = true;
return(false);
}
// Exit quickly if we know that the provided key isn't assignable to the key type for this rule
if (!TypeFinder.IsTypeAssignableFrom(declaredKeyType, providedKeyType))
{
return(false);
}
// We only need to parse the values of the parameters once for the life of the application
// since it's based from configuration
if (!_parameterValueCache.Any())
{
using (new WriteLockDisposable(_delegateCompilerLocker))
{
// Lock double-check
if (!_parameterValueCache.Any())
{
foreach (var parameter in Params.Cast <CachePolicyPickerRuleParameter>())
{
var paramType = Type.GetType(parameter.Type, false, true);
if (paramType == null)
{
return(false);
}
object value = null;
TypeConverter converter = TypeDescriptor.GetConverter(typeof(string));
if (converter.CanConvertTo(paramType))
{
value = converter.ConvertTo(parameter.ValueAsString, paramType);
}
// Don't bother converting the other way if we already got a value
if (value == null)
{
converter = TypeDescriptor.GetConverter(paramType);
if (converter.CanConvertFrom(typeof(string)))
{
value = converter.ConvertFrom(parameter.ValueAsString);
}
}
// If we couldn't parse one of the parameters, then we can essentially
// turn off this entire rule
if (value == null)
{
_couldNotParseParameterValue = true;
return(false);
}
_parameterValueCache.Add(value);
}
}
}
}
try
{
if (_dynamicDelegate == null)
{
using (new WriteLockDisposable(_delegateCompilerLocker))
{
if (_dynamicDelegate == null)
{
var lambda = System.Linq.Dynamic.DynamicExpression.ParseLambda(providedKeyType, typeof(bool), Expression, _parameterValueCache.ToArray());
_dynamicDelegate = lambda.Compile();
}
}
}
if (_dynamicDelegate == null)
{
_couldNotParseExpressionAgainstTypes.Add(providedKeyType);
return(false);
}
var result = _dynamicDelegate.DynamicInvoke(new[] { providedKeyInstance }) as bool?;
if (result.HasValue)
{
return(result.Value);
}
}
catch (Exception ex)
{
LogHelper.Warn <General>("Could not parse cache policy rule [{0}], message: {1}".InvariantFormat(Expression, ex.Message));
}
return(false);
}
