/// <summary>
/// Defines a 'unique inside of DbSet' validator on the current rule builder.
/// Validation will fail if the value of the property is not unique within the column
/// of the given <paramref name="dbSet"/>.
/// The column is specified by <paramref name="getColumnSelector"/>.
/// </summary>
/// <param name="ruleBuilder"></param>
/// <param name="dbSet"></param>
/// <param name="getColumnSelector">
/// Determines the column, with which we will compare the value of the property.
/// </param>
/// <typeparam name="TObject">
/// Type of object being validated
/// </typeparam>
/// <typeparam name="TProperty">
/// Type of property being validated
/// </typeparam>
/// <typeparam name="TEntity">
/// Type of entity, with which <paramref name="dbSet"/> operates
/// </typeparam>
/// <returns></returns>
public static IRuleBuilderOptions <TObject, TProperty> UniqueInsideOfDbSetColumn <TObject, TProperty, TEntity>(
this IRuleBuilder <TObject, TProperty> ruleBuilder,
DbSet <TEntity> dbSet, Expression <Func <TEntity, TProperty> > getColumnSelector)
where TObject : class
where TEntity : class
{
return(ruleBuilder
.MustAsync
(
(newTitle, token) => EfCoreValidationHelpers.IsValueUniqueInsideOfDbSetColumnAsync
(dbSet, getColumnSelector, newTitle, token)
)
.WithMessage("{PropertyName} must be unique"));
}
