MinLength / MaxLength

A value constraint of type MinLength or MaxLength defines a minimum or maximum length of a string value:

• MinLength means a string is at least X characters long.

• MaxLength means a string no longer than X characters long.

Note that because the columns for value constraint and value constraint type are not repeatable in the base DCTAP model, these value constraint types cannot be used to indicate ranges (eg, “2 to 9”). Users who need to express value ranges should consider extending DCTAP, for example as follows:

• With a single column that uses an application-specific syntax for ranges (eg, “1-6”).

• With two columns: one for MinInclusive and one for MaxInclusive.

propertyID	valueConstraint	valueConstraintType
:identifier	3	MinLength
:identifier	3.1	MinLength
:identifier	-10	MaxLength
:identifier	info@example.org	MaxLength

This is interpreted as:

DCTAP instance
    Shape
        shapeID                  default
        Statement Template
            propertyID           :identifier
            valueConstraint      3
            valueConstraintType  minlength
        Statement Template
            propertyID           :identifier
            valueConstraint      3.1
            valueConstraintType  minlength
        Statement Template
            propertyID           :identifier
            valueConstraint      -10
            valueConstraintType  maxlength
        Statement Template
            propertyID           :identifier
            valueConstraint      info@example.org
            valueConstraintType  maxlength

WARNING [default/valueConstraint] Value constraint type is 'minlength', but '3.1' is not an integer.
WARNING [default/valueConstraint] Value constraint type is 'maxlength', but 'info@example.org' is not an integer.

Values of type MinLength or MaxLength must be integers. Note:

• String and float values trigger warnings but are passed through, untouched, as string values.

• Negative integers do not trigger warnings, though they may not make sense.