/// <summary>
/// Retrieves an attribute that applies to a specific dialect.
/// </summary>
/// <typeparam name="T">The attribute to retrieve.</typeparam>
/// <param name="dialect">A dialect that the attribute should apply to.</param>
/// <param name="property">The property that the attribute is applied to.</param>
/// <returns>An attribute for the given property. This will be <c>null</c> when no attribute is present.</returns>
/// <exception cref="ArgumentNullException"><paramref name="dialect"/> or <paramref name="property"/> is <c>null</c>.</exception>
/// <exception cref="ArgumentException">More than one matching attribute was found.</exception>
public static T GetDialectAttribute <T>(this IDatabaseDialect dialect, PropertyInfo property) where T : ModelledSchemaAttribute
{
if (dialect == null)
{
throw new ArgumentNullException(nameof(dialect));
}
if (property == null)
{
throw new ArgumentNullException(nameof(property));
}
var dialectType = dialect.GetType();
var attrs = property.GetCustomAttributes <T>(true)
.Where(attr => attr.SupportsDialect(dialectType))
.ToList();
if (attrs.Count > 1)
{
throw new ArgumentException($"More than one matching { typeof(T).FullName } attribute was found for the property { property.Name } in { property.ReflectedType.FullName }.", nameof(property));
}
return(attrs.SingleOrDefault());
}
public ReflectionColumnDataType(IDatabaseDialect dialect, Type columnType, Type clrType)
{
if (dialect == null)
{
throw new ArgumentNullException(nameof(dialect));
}
if (columnType == null)
{
throw new ArgumentNullException(nameof(columnType));
}
if (clrType == null)
{
throw new ArgumentNullException(nameof(clrType));
}
var attr = dialect.GetDialectAttribute <DeclaredTypeAttribute>(columnType);
if (attr == null)
{
throw new ArgumentException($"The column type { columnType.FullName } does not contain a definition for the dialect { dialect.GetType().FullName }");
}
var typeProvider = dialect.TypeProvider;
if (typeProvider == null)
{
throw new ArgumentException("The given dialect does not contain a valid type provider.", nameof(dialect));
}
var collationAttr = dialect.GetDialectAttribute <CollationAttribute>(columnType);
var typeMetadata = new ColumnTypeMetadata
{
ClrType = clrType,
Collation = collationAttr?.CollationName != null
? Option <Identifier> .Some(collationAttr.CollationName)
: Option <Identifier> .None,
DataType = attr.DataType,
IsFixedLength = attr.IsFixedLength,
MaxLength = attr.Length,
NumericPrecision = attr.Precision > 0 && attr.Scale > 0
? Option <INumericPrecision> .Some(new NumericPrecision(attr.Precision, attr.Scale))
: Option <INumericPrecision> .None,
};
var dbType = typeProvider.CreateColumnType(typeMetadata);
// map dbType to properties, avoids keeping a reference
TypeName = dbType.TypeName;
DataType = dbType.DataType;
Definition = dbType.Definition;
IsFixedLength = dbType.IsFixedLength;
MaxLength = dbType.MaxLength;
ClrType = dbType.ClrType;
NumericPrecision = dbType.NumericPrecision;
Collation = dbType.Collation;
}
