4.3. Validator Reference

A quick reference to the built-in Archetypes validators.

Using Validators

Archetypes fields may have validators specified in the Field schema. For example, the schema for the basic page type includes the stanza:

ATDocumentSchema = ATContentTypeSchema.copy() + Schema((
    TextField('text',
...
              validators = ('isTidyHtmlWithCleanup',),
...
    ),

This specifies that the isTidyHtmlWithCleanup test will be applied to validate form input.

You may specify a sequence of validators:

validators = ('isMaxSize', 'isTidyHtmlWithCleanup',),

and the validators will tested in order.

The validators sequence may contain two kinds of entries:

The string names of validators registered with the validation service (see Products.validation);
Instances of classes implementing the IValidator interface (Products.validation.interfaces.IValidator.IValidator).

A validation specification using a validator class instance can look like:

validators = ( ExpressionValidator('python: int(value) == 5'), )

Registered Validators

These are validators pre-registered with the validation service. They may be specified by name.

Name	Use	Details
isDecimal	Is the input a decimal number.	Allows exponent notation.
isInt	Is the input an integer.
isPrintable	Does not contain unprintable characters	r'[a-zA-Z0-9\s]+$'
isSSN	Is a well-formed social-security number	Very naive: r'^\d{9}$'
isUSPhoneNumber	Is a valid US phone number	Looks for 10 digits, ignores spaces, parens and dashes
isInternationalPhoneNumber	Is a valid international phone number	Looks for any number of digits, ignores spaces, parens and dashes
isZipCode	Very naive: is five or nine digits
isURL	Is a valid URL	Recognizes most protocols
isEmail	Is a valid e-mail address	A pretty good regular expression test
isMailTo	Is an e-mail address preceded by "mailto:"
isUnixLikeName	Passes the basic test to be a Unix-style name	r"^[A-Za-z][\w\d\-\_]{0,7}$"
isMaxSize	Tests if an upload, file or something supporting len() is smaller than a given max size value.	Tests against a maxsize attribute on the field
isValidDate	Tests whether or not input value can be converted to a DateTime object.
isEmpty	Input value must be empty.
isEmptyNoError	Input value must be empty.	Validation will fail if input value is not empty; but no error will show.
isValidId	Input value is a valid identifier.
isTidyHtml	Uses mx.Tidy to validate HTML input. Fails on errors and warnings.
isTidyHtmlWithCleanup	Uses mx.Tidy to validate HTML input. Fails only on errors; cleans up.
isNonEmptyFile	The uploaded file is not empty.
isTAL	Validates as Template Attribute Language

Useful Validation Classes

These classes are useful for creating your own validation class instances. Imports and prototypes are shown. See source for details.

ExpressionValidator

Evaluates an expression to test the input value.

from Products.validation.validators.ExpressionValidator import ExpressionValidator

def ExpressionValidator(expression=None, errormsg=None)

RegexValidator

Tests value against a regular expression after removing ignore

characters.

from Products.validation.validators.RegexValidator import RegexValidator

def RegexValidator(name, regex, title=name, description='',
 errmsg='fails tests of %s' % name, ignore=None)

RangeValidator

Tests to see if specified minval <= input_value < maxval

from Products.validation.validators.RangeValidator import RangeValidator

def RangeValidator(name, minval=0.0, maxval=0.0, title='', description='')

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