NAME
Data::Validate - common data validation methods
SYNOPSIS
use Data::Validate wq(:math);
if(defined(is_integer($suspect))){
print "Looks like an integer\n";
}
my $name = is_alphanumeric($suspect);
if(defined($name)){
print "$name is alphanumeric, and has been untainted\n";
} else {
print "$suspect was not alphanumeric"
}
# or as an object
my $v = Data::Validate->new();
die "'foo' is not an integer" unless defined($v->is_integer('foo'));
DESCRIPTION
This module collects common validation routines to make input
validation, and untainting easier and more readable. Most of the
functions are not much shorter than their direct perl equivalent (and
are much longer in some cases), but their names make it clear what
you're trying to test for.
Almost all functions return an untainted value if the test passes, and
undef if it fails. This means that you should always check for a defined
status explicitly. Don't assume the return will be true. (e.g.
is_integer(0))
The value to test is always the first (and often only) argument.
FUNCTIONS
new - constructor for OO usage
new();
*Description*
Returns a Data::Validator object. This lets you access all the
validator function calls as methods without importing them into
your namespace or using the clumsy
Data::Validate::function_name() format.
*Arguments*
None
*Returns*
Returns a Data::Validate object
is_integer - is the value an integer?
is_integer($value);
*Description*
Returns the untainted number if the test value is an integer, or
can be cast to one without a loss of precision. (i.e. 1.0 is
considered an integer, but 1.0001 is not.)
*Arguments*
$value
The potential integer to test.
*Returns*
Returns the untainted integer on success, undef on failure. Note
that the return can be 0, so always check with defined()
*Notes, Exceptions, & Bugs*
Number translation is done by POSIX casting tools (strtol).
is_numeric - is the value numeric?
is_numeric($value);
*Description*
Returns the untainted number if the test value is numeric, or
can be cast to a number without a any bits being left over.
(i.e. 1.0 is considered a number, 1.0hello is not.)
*Arguments*
$value
The potential number to test.
*Returns*
Returns the untainted number on success, undef on failure. Note
that the return can be 0, so always check with defined()
*Notes, Exceptions, & Bugs*
Number translation is done by POSIX casting tools (strtol).
is_between - is the value between to numbers?
is_between($value, $min, $max);
*Description*
Returns the untainted number if the test value is numeric, and
falls between $min and $max inclusive. Note that either $min or
$max can be undef, which means 'unlimited'. i.e.
is_between($val, 0, undef) would pass for any number zero or
larger.
*Arguments*
$value
The potential number to test.
$min
The minimum valid value. Unlimited if set to undef
$max
The maximum valid value. Unlimited if set to undef
*Returns*
Returns the untainted number on success, undef on failure. Note
that the return can be 0, so always check with defined()
is_greater_than - is the value greater than a threshold?
is_greater_than($value, $threshold);
*Description*
Returns the untainted number if the test value is numeric, and
is greater than $threshold. (not inclusive)
*Arguments*
$value
The potential number to test.
$threshold
The minimum value (non-inclusive)
*Returns*
Returns the untainted number on success, undef on failure. Note
that the return can be 0, so always check with defined()
is_less_than - is the value less than a threshold?
is_less_than($value, $threshold);
*Description*
Returns the untainted number if the test value is numeric, and
is less than $threshold. (not inclusive)
*Arguments*
$value
The potential number to test.
$threshold
The maximum value (non-inclusive)
*Returns*
Returns the untainted number on success, undef on failure. Note
that the return can be 0, so always check with defined()
is_equal_to - do a string/number neutral ==
is_equal_to($value, $target);
*Description*
Returns the target if $value is equal to it. Does a math
comparison if both $value and $target are numeric, or a string
comparison otherwise. Both the $value and $target must be
defined to get a true return. (i.e. undef != undef)
*Arguments*
$value
The value to test.
$target
The value to test against
*Returns*
Unlike most validator routines, this one does not necessarily
untaint its return value, it just returns $target. This has the
effect of untainting if the target is a constant or other clean
value. (i.e. is_equal_to($bar, 'foo')). Note that the return can
be 0, so always check with defined()
is_even - is a number even?
is_even($value);
*Description*
Returns the untainted $value if it's numeric, an integer, and
even.
*Arguments*
$value
The value to test.
*Returns*
Returns $value (untainted). Note that the return can be 0, so
always check with defined().
is_odd - is a number odd?
is_odd($value);
*Description*
Returns the untainted $value if it's numeric, an integer, and
odd.
*Arguments*
$value
The value to test.
*Returns*
Returns $value (untainted). Note that the return can be 0, so
always check with defined().
is_alphanumeric - does it only contain letters and numbers?
is_alphanumeric($value);
*Description*
Returns the untainted $value if it is defined and only contains
letters (upper or lower case) and numbers. Also allows an empty
string - ''.
*Arguments*
$value
The value to test.
*Returns*
Returns $value (untainted). Note that the return can be 0, so
always check with defined().
is_printable - does it only contain printable characters?
is_alphanumeric($value);
*Description*
Returns the untainted $value if it is defined and only contains
printable characters as defined by the composite POSIX character
class [[:print:][:space:]]. Also allows an empty string - ''.
*Arguments*
$value
The value to test.
*Returns*
Returns $value (untainted). Note that the return can be 0, so
always check with defined().
length_is_between - is the string length between two limits?
length_is_between($value, $min, $max);
*Description*
Returns $value if it is defined and its length is between $min
and $max inclusive. Note that this function does not untaint the
value.
If either $min or $max are undefined they are treated as
no-limit.
*Arguments*
$value
The value to test.
$min
The minimum length of the string (inclusive).
$max
The maximum length of the string (inclusive).
*Returns*
Returns $value. Note that the return can be 0, so always check
with defined(). The value is not automatically untainted.
AUTHOR
Richard Sonnen .
COPYRIGHT
Copyright (c) 2004 Richard Sonnen. All rights reserved.
This program is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.