/// <summary>
/// Determines if the specified EdmMember is a concurrency timestamp.
/// </summary>
/// <remarks>Since EF doesn't expose "timestamp" as a first class
/// concept, we use the below criteria to infer this for ourselves.
/// </remarks>
/// <param name="member">The member to check.</param>
/// <returns>True or false.</returns>
public static bool IsConcurrencyTimestamp(EdmMember member)
{
Facet facet = member.TypeUsage.Facets.SingleOrDefault(p => p.Name == "ConcurrencyMode");
if (facet == null || facet.Value == null || (ConcurrencyMode)facet.Value != ConcurrencyMode.Fixed)
{
return(false);
}
facet = member.TypeUsage.Facets.SingleOrDefault(p => p.Name == "FixedLength");
if (facet == null || facet.Value == null || !((bool)facet.Value))
{
return(false);
}
facet = member.TypeUsage.Facets.SingleOrDefault(p => p.Name == "MaxLength");
if (facet == null || facet.Value == null || (int)facet.Value != 8)
{
return(false);
}
MetadataProperty md = ObjectContextUtilities.GetStoreGeneratedPattern(member);
if (md == null || facet.Value == null || (string)md.Value != "Computed")
{
return(false);
}
return(true);
}
/// <summary>
/// Returns a collection of all the <see cref="Attribute"/>s we infer from the metadata associated
/// with the metadata member corresponding to the given property descriptor
/// </summary>
/// <param name="pd">A <see cref="PropertyDescriptor"/> to examine</param>
/// <returns>A collection of attributes inferred from the metadata in the given descriptor.</returns>
protected override IEnumerable <Attribute> GetMemberAttributes(PropertyDescriptor pd)
{
List <Attribute> attributes = new List <Attribute>();
// Exclude any EntityState, EntityReference, etc. members
if (ShouldExcludeEntityMember(pd))
{
// for these members, we don't want to do any further
// attribute inference
attributes.Add(new ExcludeAttribute());
return(attributes.ToArray());
}
EditableAttribute editableAttribute = null;
bool inferRoundtripOriginalAttribute = false;
bool hasKeyAttribute = (pd.Attributes[typeof(KeyAttribute)] != null);
bool isEntity = this.EdmType.BuiltInTypeKind == BuiltInTypeKind.EntityType;
if (isEntity)
{
EntityType entityType = (EntityType)this.EdmType;
EdmMember keyMember = entityType.KeyMembers.SingleOrDefault(k => k.Name == pd.Name);
if (keyMember != null && !hasKeyAttribute)
{
attributes.Add(new KeyAttribute());
hasKeyAttribute = true;
}
}
EdmProperty member = this.EdmType.Members.SingleOrDefault(p => p.Name == pd.Name) as EdmProperty;
if (member != null)
{
if (hasKeyAttribute)
{
// key members must always be roundtripped
inferRoundtripOriginalAttribute = true;
// key members that aren't also FK members are non-editable (but allow an initial value)
if (!this._keyIsEditable)
{
editableAttribute = new EditableAttribute(false)
{
AllowInitialValue = true
};
}
}
// Check if the member is DB generated and add the DatabaseGeneratedAttribute to it if not already present.
if (pd.Attributes[typeof(System.ComponentModel.DataAnnotations.Schema.DatabaseGeneratedAttribute)] == null)
{
MetadataProperty md = ObjectContextUtilities.GetStoreGeneratedPattern(member);
if (md != null)
{
if ((string)md.Value == "Computed")
{
attributes.Add(new System.ComponentModel.DataAnnotations.Schema.DatabaseGeneratedAttribute(System.ComponentModel.DataAnnotations.Schema.DatabaseGeneratedOption.Computed));
}
else if ((string)md.Value == "Identity")
{
attributes.Add(new System.ComponentModel.DataAnnotations.Schema.DatabaseGeneratedAttribute(System.ComponentModel.DataAnnotations.Schema.DatabaseGeneratedOption.Identity));
}
}
}
// Add implicit ConcurrencyCheck attribute to metadata if ConcurrencyMode is anything other than ConcurrencyMode.None
Facet facet = member.TypeUsage.Facets.SingleOrDefault(p => p.Name == "ConcurrencyMode");
if (facet != null && facet.Value != null && (ConcurrencyMode)facet.Value != ConcurrencyMode.None &&
pd.Attributes[typeof(ConcurrencyCheckAttribute)] == null)
{
attributes.Add(new ConcurrencyCheckAttribute());
inferRoundtripOriginalAttribute = true;
}
bool isStringType = pd.PropertyType == typeof(string) || pd.PropertyType == typeof(char[]);
// Add Required attribute to metadata if the member cannot be null and it is either a reference type or a Nullable<T>
// unless it is a database generated field
if (!member.Nullable && (!pd.PropertyType.IsValueType || IsNullableType(pd.PropertyType)) &&
!pd.Attributes.OfType <DatabaseGeneratedAttribute>().Any(dga => dga.DatabaseGeneratedOption != DatabaseGeneratedOption.None) &&
pd.Attributes[typeof(RequiredAttribute)] == null)
{
attributes.Add(new RequiredAttribute());
}
if (isStringType &&
pd.Attributes[typeof(StringLengthAttribute)] == null)
{
facet = member.TypeUsage.Facets.SingleOrDefault(p => p.Name == "MaxLength");
if (facet != null && facet.Value != null && facet.Value.GetType() == typeof(int))
{
// need to test for Type int, since the value can also be of type
// System.Data.Metadata.Edm.EdmConstants.Unbounded
int maxLength = (int)facet.Value;
attributes.Add(new StringLengthAttribute(maxLength));
}
}
bool hasTimestampAttribute = (pd.Attributes[typeof(TimestampAttribute)] != null);
if (this._timestampMember == member && !hasTimestampAttribute)
{
attributes.Add(new TimestampAttribute());
hasTimestampAttribute = true;
}
// All members marked with TimestampAttribute (inferred or explicit) need to
// have [Editable(false)] and [RoundtripOriginal] applied
if (hasTimestampAttribute)
{
inferRoundtripOriginalAttribute = true;
if (editableAttribute == null)
{
editableAttribute = new EditableAttribute(false);
}
}
// Add RTO to this member if required. If this type has a timestamp
// member that member should be the ONLY member we apply RTO to.
// Dont apply RTO if it is an association member.
bool isForeignKeyMember = this._foreignKeyMembers != null && this._foreignKeyMembers.Contains(member);
if ((this._timestampMember == null || this._timestampMember == member) &&
(inferRoundtripOriginalAttribute || isForeignKeyMember) &&
pd.Attributes[typeof(AssociationAttribute)] == null)
{
if (pd.Attributes[typeof(RoundtripOriginalAttribute)] == null)
{
attributes.Add(new RoundtripOriginalAttribute());
}
}
}
// Add the Editable attribute if required
if (editableAttribute != null && pd.Attributes[typeof(EditableAttribute)] == null)
{
attributes.Add(editableAttribute);
}
if (isEntity)
{
this.AddAssociationAttributes(pd, attributes);
}
return(attributes.ToArray());
}
