NAME
Validation::Class - Low-Fat Full-Flavored Data Validation Construction
Kit
VERSION
version 5.22
SYNOPSIS
use MyApp::Validation;
my $input = MyApp::Validation->new(params => $params);
unless ($input->validate('user', 'pass')){
return $input->errors_to_string;
}
unless ($input->validate_profile('registration')) {
return $input->errors_to_string;
}
DESCRIPTION
Validation::Class takes a different approach towards data validation,
... it attempts to simplify and centralize data validation rules to
ensure DRY (don't repeat yourself) code. The primary intent of this
module is to provide a simplistic data modeling/validation framework.
Your validation class can be thought of as your data input firewall
which can be used anywhere and is flexible enough in an MVC environment
to be used in the Controller and Model alike.
The benefits this approach provides might require you to change your
perspective on parameter handling. Typically when designing an
application we tend to name parameters arbitrarily with the only purpose
being to identify incoming data within a script on a per use-case basis.
To get the most out of Validation::Class you should consider each
parameter hitting your application (individually) as a transmission
fitting a very specific criteria. Your validation rules will act as
filters which will reject or accept and format the transmission for use
within your application. Yes, .. almost exactly like a firewall.
A validation class is defined as follows:
package MyApp::Validation;
use Validation::Class;
# a mixin template
mxn 'basic' => {
required => 1
};
# a validation rule
fld 'login' => {
label => 'User Login',
error => 'Login invalid.',
mixin => 'basic',
validation => sub {
my ($self, $this_field, $all_params) = @_;
return $this_field->{value} eq 'admin' ? 1 : 0;
}
};
# a validation rule
fld 'password' => {
label => 'User Password',
error => 'Password invalid.',
mixin => 'basic',
validation => sub {
my ($self, $this_field, $all_params) = @_;
return $this_field->{value} eq 'pass' ? 1 : 0;
}
};
# a validation profile
pro 'registration' => sub {
my ($self, @args) = shift;
return $self->validate(qw(
+name
+email
-login
+password
))
};
1;
The fields defined will be used to validate the specified input
parameters. You specify the input parameters at instantiation,
parameters should take the form of a hashref of key/value pairs.
Multi-level (nested) hashrefs are allowed and are inflated/deflated in
accordance with the rules of Hash::Flatten. The following is an example
on using your validate class to validate input in various scenarios:
# web app
package MyApp;
use MyApp::Validation;
use Misc::WebAppFramework;
get '/auth' => sub {
# get user input parameters
my $params = shift;
# initialize validation class and set input parameters
my $rules = MyApp::Validation->new(params => $params);
unless ($rules->validate('login', 'password')) {
# print errors to browser unless validation is successful
return $rules->errors_to_string;
}
return 'you have authenticated';
};
BUILDING A VALIDATION CLASS
package MyApp::Validation;
use Validation::Class;
# a validation rule template
mixin 'basic' => {
required => 1,
min_length => 1,
max_length => 255,
filters => ['lowercase', 'alphanumeric']
};
# a validation rule
field 'user.login' => {
mixin => 'basic',
label => 'user login',
error => 'login invalid',
validation => sub {
my ($self, $this, $fields) = @_;
return $this->{value} eq 'admin' ? 1 : 0;
}
};
# a validation rule
field 'user.password' => {
mixin => 'basic',
label => 'user login',
error => 'login invalid',
validation => sub {
my ($self, $this, $fields) = @_;
return $this->{value} eq 'pass' ? 1 : 0;
}
};
1;
THE MIXIN KEYWORD
The mixin keyword (or mxn) creates a validation rules template that can
be applied to any field using the mixin directive.
package MyApp::Validation;
use Validation::Class;
mixin 'constrain' => {
required => 1,
min_length => 1,
max_length => 255,
...
};
# e.g.
field 'login' => {
mixin => 'constrain',
...
};
THE FILTER KEYWORD
The filter keyword (or flt) creates custom filters to be used in your
field definitions.
package MyApp::Validation;
use Validation::Class;
filter 'usa_telephone_number_converter' => sub {
$_[0] =~ s/\D//g;
my ($ac, $pre, $num) = $_[0] =~ /(\d{3})(\d{3})(\d{4})/;
$_[0] = "($ac) $pre-$num";
};
# e.g.
field 'my_telephone' => {
filter => ['trim', 'usa_telephone_number_converter'],
...
};
THE DIRECTIVE KEYWORD
The directive keyword (or dir) creates custom validator directives to be
used in your field definitions. The routine is passed two parameters,
the value of directive and the value of the field the validator is being
processed against. The validator should return true or false.
package MyApp::Validation;
use Validation::Class;
directive 'between' => sub {
my ($directive, $value, $field, $class) = @_;
my ($min, $max) = split /\-/, $directive;
unless ($value > $min && $value < $max) {
my $handle = $field->{label} || $field->{name};
$class->error($field, "$handle must be between $directive");
return 0;
}
return 1;
};
# e.g.
field 'hours' => {
between => '00-24',
...
};
THE FIELD KEYWORD
The field keyword (or fld) creates a validation block and defines
validation rules for reuse in code. The field keyword should correspond
with the parameter name expected to be passed to your validation class.
package MyApp::Validation;
use Validation::Class;
field 'login' => {
required => 1,
min_length => 1,
max_length => 255,
...
};
The field keyword takes two arguments, the field name and a hashref of
key/values pairs.
THE PROFILE KEYWORD
The profile keyword (or pro) stores a validation profile (coderef) which
as in the traditional use of the term is a sequence of validation
routines that validate data relevant to a specific action. The profile
keyword takes a name and coderef as arguments.
package MyApp::Validation;
use Validation::Class;
profile 'app_signup' => sub {
my ($self, @args) = @_;
return $self->validate(qw(
+name
+email
+email_confirmation
-login
+password
+password_confirmation
));
};
package main;
my $val = MyApp::Validation->new(params => $params);
unless ($val->validate_profile('app_signup')) {
die $val->errors_to_string;
}
The field keyword takes two arguments, the field name and a hashref of
key/values pairs.
FILTERING INCOMING DATA
Validation::Class supports pre/post filtering but is configured to
pre-filter incoming data. This means that based upon the filtering
options supplied within the individual fields, filtering will happen
before validation (technically at instantiation and again just before
validation). As expected, this is configurable via the filtering
attribute.
A WORD OF CAUTION: Validation::Class is configured to pre-filter
incoming data which boosts application security and is best used with
passive filtering (e.g. converting character case - filtering which only
alters the input in predictable ways), versus aggressive filtering (e.g.
formatting a telephone number) which completely and permanently changes
the incoming data ... so much so that if the validation still fails ...
errors that are reported may not match the data that was submitted.
If you're sure you'd rather employ aggressive filtering, I suggest
setting the filtering attribute to 'post' for post-filtering or setting
it to null and applying the filters manually by calling the
apply_filters() method.
AUTO-SERIALIZATION/DESERIALIZATION
Validation::Class supports automatic serialization and deserialization
of parameters with complex data structures which means that you can set
a parameter as an arrayref or hashref of nested data structures and
validate against them, likewise you can set a parameters using parameter
names which are serialized string representations of the keys within the
complex structure you wish to set and validate against. The
serialization rules are as documented in Hash::Flatten.
The following is an example of that:
my $params = {
user => {
login => 'admin',
password => 'pass'
}
};
my $rules = MyApp::Validation->new(params => $params);
# or
my $params = {
'user.login' => 'admin',
'user.password' => 'pass'
};
my $rules = MyApp::Validation->new(params => $params);
# field definition using field('user.login', ...)
# and field('user.password', ...) will match against the parameters above
# after filtering, validation, etc ... return your params as a hashref if
# needed
my $params = $rules->get_params_hash;
SEPARATION OF CONCERNS
For larger applications where a single validation class might become
cluttered and inefficient, Validation::Class comes equipped to help you
separate your validation rules into separate classes.
The idea is that you'll end up with a main validation class (most likely
empty) that will simply serve as your point of entry into your relative
(child) classes. The following is an example of this:
package MyVal::User;
use Validation::Class;
field name => { ... };
field email => { ... };
field login => { ... };
field password => { ... };
package MyVal::Profile;
use Validation::Class;
field age => { ... };
field sex => { ... };
field birthday => { ... };
package MyVal;
use Validation::Class;
load { classes => 1 };
package main;
my $rules = MyVal->new(params => $params);
my $user = $rules->class('user');
my $profile = $rules->class('profile');
...
1;
DEFAULT FIELD/MIXIN DIRECTIVES
package MyApp::Validation;
use Validation::Class;
# a validation template
mixin '...' => {
# mixin directives here
...
};
# a validation rule
field '...' => {
# field directives here
...
};
1;
When building a validation class, the first encountered and arguably two
most important keyword functions are field() and mixin(), which are used
to declare their respective properties. A mixin() declares a validation
template where its properties are intended to be copied within field()
declarations which declares validation rules, filters and other
properties.
Both the field() and mixin() declarations/functions require two
parameters, the first being a name, used to identify the declaration and
to be matched against incoming input parameters and the second being a
hashref of key/value pairs. The key(s) within a declaration are commonly
referred to as directives.
The following is a list of default directives which can be used in
field/mixin declarations:
alias
The alias directive is useful when many different parameters with
different names can be validated using a single rule. E.g. The paging
parameters in a webapp may take on different names but require the same
validation.
# the alias directive
field 'pager' => {
alias => ['page_user_list', 'page_other_list']
...
};
default
The default directive is used as a default value for a field to be used
when a matching parameter is not present.
# the default directive
field 'quantity' => {
default => 1,
...
};
error/errors
The error/errors directive is used to replace the system generated error
messages when a particular field doesn't validate. If a field fails
multiple directives, multiple errors will be generated for the same
field. This may not be desirable, the error directive overrides this
behavior and only the specified error is registered and displayed.
# the error(s) directive
field 'foobar' => {
errors => 'Foobar failed processing, Wtf?',
...
};
filtering
The filtering directive is used to control when field filters are
applied. The default recognized values are pre/post. A value of 'pre'
instructs the validation class to apply the field's filters at
instantiation and before validation whereas a value of 'post' instructs
the validation class to apply the field's filters after validation.
Alternatively, a value of undef or '' will bypass filtering altogether.
# the filtering directive
field 'foobar' => {
filtering => 'post',
...
};
label
The label directive is used as a user-friendly reference when the field
name is a serialized hash key or just plain ugly.
# the label directive
field 'hashref.foo.bar' => {
label => 'Foo Bar',
...
};
mixin
The mixin directive is used to create a template of directives to be
applied to other fields.
mixin 'ID' => {
required => 1,
min_length => 1,
max_length => 11
};
# the mixin directive
field 'user.id' => {
mixin => 'ID',
...
};
mixin_field
The mixin directive is used to copy all directives from an existing
field except for the name, label, and validation directives.
# the mixin_field directive
field 'foobar' => {
label => 'Foo Bar',
required => 1
};
field 'barbaz' => {
mixin_field => 'foobar',
label => 'Bar Baz',
...
};
name
The name directive is used *internally* and cannot be changed.
# the name directive
field 'thename' => {
...
};
required
The required directive is an important directive but can be
misunderstood. The required directive is used to ensure the submitted
parameter exists and has a value. If the parameter is never submitted,
the directive is effectively skipped. This directive can be thought of
as the "must-have-a-value-if-exists" directive.
# the required directive
field 'foobar' => {
required => 1,
...
};
# fail
my $rules = MyApp::Validation->new(params => { });
$rules->validate('foobar');
# fail
my $rules = MyApp::Validation->new(params => { foobar => '' });
$rules->validate('foobar');
# pass
my $rules = MyApp::Validation->new(params => { foobar => 'Nice' });
$rules->validate('foobar');
See the toggle functionality within the validate() method. This method
allows you to temporarily alter whether a field is required or not.
validation
The validation directive is a coderef used add additional custom
validation to the field. The coderef must return true (to pass) or false
(to fail). Custom error messages can be set from within the coderef so
make sure they are set based on appropriate logic as the registration of
error message are not contingent on the success or failure of the
routine.
# the validation directive
field 'login' => {
validation => sub {
my ($self, $this_field, $all_params) = @_;
return 0 unless $this_field->{value};
return $this_field->{value} eq 'admin' ? 1 : 0;
},
...
};
value
The value directive is used internally to store the field's matching
parameter's value. This value can be set in the definition but SHOULD
NOT be used as a default value unless you're sure no parameter will
overwrite it during run-time. If you need to set a default value, see
the default directive.
# the value directive
field 'quantity' => {
value => 1,
...
};
DEFAULT FIELD/MIXIN FILTER DIRECTIVES
filters
The filters directive is used to correct, alter and/or format the values
of the matching input parameter. Note: Filtering is applied before
validation. The filter directive can have multiple filters (even a
coderef) in the form of an arrayref of values.
# the filter(s) directive
field 'text' => {
filters => [qw/trim strip/ => sub {
$_[0] =~ s/\D//g;
}],
...
};
The following is a list of default filters that may be used with the
filter directive:
alpha
The alpha filter removes all non-Alphabetic characters from the field's
value.
field 'foobar' => {
filter => 'alpha',
};
alphanumeric
The alpha filter removes all non-Alphabetic and non-Numeric characters
from the field's value.
field 'foobar' => {
filter => 'alphanumeric',
};
capitalize
The capitalize filter attempts to capitalize the first word in each
sentence, where sentences are separated by a period and space, within
the field's value.
field 'foobar' => {
filter => 'capitalize',
};
decimal
The decimal filter removes all non-decimal-based characters from the
field's value. Allows only: decimal, comma, and numbers.
field 'foobar' => {
filter => 'decimal',
};
numeric
The numeric filter removes all non-numeric characters from the field's
value.
field 'foobar' => {
filter => 'numeric',
};
strip
As with the trim filter the strip filter removes leading and trailing
whitespaces from the field's value and additionally removes multiple
whitespaces from between the values characters.
field 'foobar' => {
filter => 'strip',
};
titlecase
The titlecase filter converts the field's value to titlecase by
capitalizing the first letter of each word.
field 'foobar' => {
filter => 'titlecase',
};
trim
The trim filter removes leading and trailing whitespace from the field's
value.
field 'foobar' => {
filter => 'trim',
};
uppercase
The uppercase filter converts the field's value to uppercase.
field 'foobar' => {
filter => 'uppercase',
};
DEFAULT FIELD/MIXIN VALIDATOR DIRECTIVES
package MyApp::Validation;
use Validation::Class;
# a validation rule with validator directives
field 'telephone_number' => {
length => 14,
pattern => '(###) ###-####',
...
};
1;
Validator directives are special directives with associated validation
code that is used to validate common use cases such as "checking the
length of a parameter", etc.
The following is a list of the default validators which can be used in
field/mixin declarations:
between
# the between directive
field 'foobar' => {
between => '1-5',
...
};
depends_on
# the depends_on directive
field 'change_password' => {
depends_on => ['password', 'password_confirm'],
...
};
length
# the length directive
field 'foobar' => {
length => 20,
...
};
matches
# the matches directive
field 'this_field' => {
matches => 'another_field',
...
};
max_alpha
# the max_alpha directive
field 'password' => {
max_alpha => 30,
...
};
max_digits
# the max_digits directive
field 'password' => {
max_digits => 5,
...
};
max_length
# the max_length directive
field 'foobar' => {
max_length => '...',
...
};
max_sum
# the max_sum directive
field 'vacation_days' => {
max_sum => 5,
...
};
max_symbols
# the max_symbols directive
field 'password' => {
max_symbols => 1,
...
};
min_alpha
# the min_alpha directive
field 'password' => {
min_alpha => 2,
...
};
min_digits
# the min_digits directive
field 'password' => {
min_digits => 1,
...
};
min_length
# the min_length directive
field 'foobar' => {
min_length => '...',
...
};
min_sum
# the min_sum directive
field 'vacation_days' => {
min_sum => 0,
...
};
min_symbols
# the min_symbols directive
field 'password' => {
min_symbols => 0,
...
};
options
# the options directive
field 'status' => {
options => 'Active, Inactive',
...
};
pattern
# the pattern directive
field 'telephone' => {
# simple pattern
pattern => '### ###-####',
...
};
field 'country_code' => {
# simple pattern
pattern => 'XX',
filter => 'uppercase'
...
};
field 'complex' => {
# regex pattern
pattern => qr/[0-9]+\,\s\.\.\./,
...
};
THE VALIDATION CLASS
The following is an example of how to use your constructed validation
class in other code, .e.g. Web App Controller, etc.
use MyApp::Validation;
my $input = MyApp::Validation->new(params => $params);
unless ($input->validate('field1','field2')){
return $input->errors_to_string;
}
Feeling lazy? Have your validation class automatically find the
appropriate fields to validate against (params must match field names).
use MyApp::Validation;
my $input = MyApp::Validation->new(params => $params);
unless ($input->validate){
return $input->errors_to_string;
}
You can define an alias to automatically map a parameter to a validation
field whereby a field definition will have an alias attribute containing
an arrayref of alternate parameters that can be matched against
passed-in parameters.
package MyApp::Validation;
field 'foo.bar' => {
...,
alias => [
'foo',
'bar',
'baz',
'bax'
]
};
use MyApp::Validation;
my $input = MyApp::Validation->new(params => { foo => 1 });
unless ($input->validate(){
return $input->errors_to_string;
}
new
The new method instantiates and returns an instance of your validation
class.
use MyApp::Validation;
my $input = MyApp::Validation->new;
$input->params($params);
...
my $input = MyApp::Validation->new(params => $params);
...
VALIDATION CLASS ATTRIBUTES
ignore_unknown
The ignore_unknown boolean determines whether your application will live
or die upon encountering unregistered field directives during
validation. This is off (0) by default, attempts to validate unknown
fields WILL cause the program to die.
my $self = MyApp::Validation->new(params => $params, ignore_unknown => 1);
$self->ignore_unknown(1);
...
fields
The fields attribute returns a hashref of defined fields, filtered and
merged with their parameter counterparts.
my $self = MyApp::Validation->new(fields => $fields);
my $fields = $self->fields();
...
filtering
The filtering attribute (by default set to 'pre') controls when incoming
data is filtered. Setting this attribute to 'post' will defer filtering
until after validation which allows any errors messages to report errors
based on the unaltered data. Alternatively, setting the filtering
attribute to '' or undef will bypass all filtering unless explicitly
defined at the field-level.
my $self = MyApp::Validation->new(filtering => 'post');
$self->validate();
...
filters
The filters attribute returns a hashref of pre-defined filter
definitions.
my $filters = $self->filters();
...
hash_inflator
The hash_inflator value determines how the hash serializer
(inflation/deflation) behaves. The value must be a hashref of "OPTIONS"
in Hash::Flatten options. Purely for the sake of consistency, you can
use lowercase keys (with underscores) which will be converted to
camel-cased keys before passed to the serializer.
my $self = MyApp::Validation->new(
hash_inflator => {
hash_delimiter => '/',
array_delimiter => '//'
}
);
...
mixins
The mixins attribute returns a hashref of defined validation templates.
my $mixins = $self->mixins();
...
params
The params attribute gets/sets the parameters to be validated.
my $input = {
...
};
my $self = MyApp::Validation->new(params => $input);
$self->params($input);
my $params = $self->params();
...
report_unknown
The report_unknown boolean determines whether your application will
report unregistered fields as class-level errors upon encountering
unregistered field directives during validation. This is off (0) by
default, attempts to validate unknown fields will NOT be registered as
class-level variables.
my $self = MyApp::Validation->new(params => $params,
ignore_unknown => 1, report_unknown => 1);
$self->report_unknown(1);
...
stashed
The stashed attribute represents a list of field names stored to be used
in validation later. If the stashed attribute contains a list you can
omit arguments to the validate method.
$self->stashed([qw/this that .../]);
VALIDATION CLASS METHODS
apply_filters
The apply_filters method (usually called automatically based on the
filtering attribute) can be used to run the currently defined parameters
through the filters defined in the fields.
my $rules = MyVal->new(filtering => '', params => $params);
if ($rules->validate) {
$rules->apply_filters;
}
else {
print $rules->errors_to_string;
# print errors on unaltered parameters
}
class
The class method returns a new initialize child validation class under
the namespace of the calling class that issued the load_classes() method
call. Existing parameters and configuration options are passed to the
child class's constructor. All attributes can be easily overwritten
using the attribute's accessors on the child class. Also, you may
prevent/override arguments from being copy to the new child class object
by supplying the them as arguments to this method.
The class method is also quite handy in that it will detect parameters
that are prefixed with the name of the class being fetched, and adjust
the matching rule (if any) to allow validation to occur.
package MyVal;
use Validation::Class;
load {
classes => 1 # load child classes e.g. MyVal::*
};
package main;
my $rules = MyVal->new(params => $params);
my $kid1 = $rules->class('Child'); # loads MyVal::Child;
my $kid2 = $rules->class('StepChild'); # loads MyVal::StepChild;
my $kid3 = $rules->class('child'); # loads MyVal::Child;
my $kid4 = $rules->class('step_child'); # loads MyVal::StepChild;
# INTELLIGENTLY DETECTING AND MAP PARAMS TO CHILD CLASS
my $params = {
'my.name' => 'Guy Friday',
'child.name' => 'Guy Friday Jr.'
};
$rules->class('child'); # child field *name* mapped to param *child.name*
# WITHOUT COPYING PARAMS FROM MyVal
my $kid5 = $rules->class('child', params => {}); # .. etc
1;
clear_queue
The clear_queue method resets the queue container, see the queue method
for more information on queuing fields to be validated. The clear_queue
method has yet another useful behavior in that it can assign the values
of the queued parameters to the list it is passed, where the values are
assigned in the same order queued.
my $rules = MyVal->new(params => $params);
$rules->queue(qw(name +email +login +password));
unless ($rules->validate) {
return $rules->errors_to_string;
}
$rules->clear_queue(my($name, $email));
1;
clone
The clone method is used to create new fields (rules) from existing
fields on-the-fly. This is useful when you have a variable number of
parameters being validated that can share existing validation rules.
E.g., a web-form on a user's profile page may have dynamically created
input boxes for the person's phone numbers allowing the user to add
additional parameters to the web-form as needed, in that case as opposed
to having multiple validation rules hardcoded for each parameter, you
could hardcode one single rule and clone the rule at run-time.
package MyVal;
use Validation::Class;
field phone => { required => 1 };
package main;
my $rules = MyVal->new(params => $params);
# clone phone rule at run-time to validate dynamically created parameters
$rules->clone('phone', 'phone2', { label => 'Other Phone', required => 0 });
$rules->clone('phone', 'phone3', { label => 'Third Phone', required => 0 });
$rules->clone('phone', 'phone4', { label => 'Forth Phone', required => 0 });
$rules->validate(qw/phone phone2 phone3 phone4/);
1;
error
The error method is used to set and/or retrieve errors encountered
during validation. The error method with no parameters returns the error
message object which is an arrayref of error messages stored at
class-level.
# set errors at the class-level
return $self->error('this isnt cool', 'unknown somethingorother');
# set an error at the field-level, using the field ref (not field name)
$self->error($field_object, "i am your error message");
# return all errors encountered/set as an arrayref
my $all_errors = $self->error();
# return all error for a specific field, ... see the get_errors() method
my @errors = $self->get_errors('field_name');
error_count
The error_count method returns the total number of error encountered
from the last validation call.
return $self->error_count();
unless ($self->validate) {
print "Found ". $self->error_count ." Errors";
}
error_fields
The error_fields method returns a hashref of fields whose value is an
arrayref of error messages.
unless ($self->validate) {
my $bad_fields = $self->error_fields();
}
my $bad_fields = $self->error_fields('login', 'password');
errors_to_string
The errors_to_string method stringifies the error arrayref object using
the specified delimiter or ', ' by default.
return $self->errors_to_string("
\n");
return $self->errors_to_string("
\n", sub{ uc shift });
unless ($self->validate) {
return $self->errors_to_string;
}
get_errors
The get_errors method returns the list of class-level error set on the
current class or a list of errors from the specified fields.
my @errors = $self->get_errors();
my @lp_errors = $self->get_errors('login', 'password');
get_params
The get_params method returns the values (in list form) of the
parameters specified.
if ($self->validate) {
my $name_a = $self->get_params('name');
my ($name_b, $email, $login, $password) =
$self->get_params(qw/name email login password/);
# you should note that if the params dont exist they will return undef
# ... meaning you should check that it exists before checking its value
# e.g.
if (defined $name) {
if ($name eq '') {
print 'name parameter was passed but was empty';
}
}
else {
print 'name parameter was never submitted';
}
}
get_params_hash
If your fields and parameters are designed with complex hash structures,
the get_params_hash method returns the deserialized hashref of specified
parameters based on the the default or custom configuration of the hash
serializer Hash::Flatten.
my $params = {
'user.login' => 'member',
'user.password' => 'abc123456'
};
if ($self->validate(keys %$params)) {
my $params = $self->get_params_hash;
print $params->{user}->{login};
}
load
The load method provides a more structured and aesthetically pleasing
interface for configuring the current class.
package MyVal;
use Validation::Class;
# load all child classes (relatives)
load {
classes => 1
};
# load CPAN or Custom plugins
load {
plugins => [
'CPANPlugin',
'+MyVal::Plugin'
]
};
# merge configuration information from another class(es)
load {
base => [
'BaseClass'
]
};
1;
load_classes
The load_classes method (depreciated) uses Module::Find to load child
classes for convenient access through the class() method. Existing
parameters and configuration options are passed to the child class's
constructor. All attributes can be easily overwritten using the
attribute's accessors on the child class.
package MyVal;
use Validation::Class;
__PACKAGE__->load_classes;
# or
load {
classes => 1 # same as above
};
1;
load_plugins
The load_plugins method (depreciated) is used to load plugins that
support Validation::Class. A Validation::Class plugin is little more
than a Role (Moose::Role) that extends the Validation::Class core. As
usual, an official Validation::Class plugin can be referred to using
shorthand while custom plugins are called by prefixing a plus symbol to
the fully-qualified plugin name. Learn more about plugins at
Validation::Class::Plugins.
package MyVal;
use Validation::Class;
__PACKAGE__->load_plugins('SuperX');
# loads Validation::Class::Plugin::SuperX
__PACKAGE__->load_plugins('+MyApp::Validation::Plugin::SuperY');
# or
load {
plugins => [
'SuperX',
'+MyApp::Validation::Plugin::SuperY'
]
}; # same as above
1;
param
The param method returns a single parameter by name.
if ($self->param('chng_pass')) {
$self->validate('password_confirmation');
}
queue
The queue method is a convenience method used specifically to append the
stashed attribute allowing you to *queue* field to be validated. This
method also allows you to set fields that must always be validated.
# conditional validation flow WITHOUT the queue method
# imagine a user profile update action
my $rules = MyApp::Validation->new(params => $params);
my @fields = qw/name login/;
push @fields, 'email_confirm' if $rules->param('chg_email');
push @fields, 'password_confirm' if $rules->param('chg_pass');
... if $rules->validate(@fields);
# conditional validation WITH the queue method
my $rules = MyApp::Validation->new(params => $params);
$rules->queue(qw/name login/);
$rules->queue(qw/email_confirm/) if $rules->param('chg_email');
$rules->queue(qw/password_confirm/) if $rules->param('chg_pass');
... if $rules->validate();
# set fields that must ALWAYS be validated
# imagine a simple REST server
my $rules = MyApp::Validation->new(params => $params);
$rules->queue(qw/login password/);
if ($request eq '/resource/:id') {
if ($rules->validate('id')) {
# validated login, password and id
...
}
}
reset
The reset method clears all errors, fields and stashed field names, both
at the class and individual field levels.
$self->reset();
reset_errors
The reset_errors method clears all errors, both at the class and
individual field levels. This method is called automatically every time
the validate() method is triggered.
$self->reset_errors();
reset_fields
The reset_fields method clears all errors and field values, both at the
class and individual field levels. This method is executed automatically
at instantiation.
$self->reset_fields();
sanitize
The sanitize method executes a set of routines that reset the parameter
environment filtering any parameters present. This method is executed
automatically at instantiation and validation.
$self->sanitize();
set_errors
The set_errors method pushes its arguments (error messages) onto the
class-level error stack of the current class.
my $count = $self->set_errors('Oops', 'OMG', 'WTF');
set_method
The set_method method conveniently creates a method on the calling
class, this method is primarily intended to be used during instantiation
of a plugin during instantiation of the validation class.
Additionally, method names are flattened, e.g. ThisPackage will be
converted to this_package for convenience and consistency.
my $sub = $self->set_method(__PACKAGE__ => sub { ... });
set_params_hash
Depending on how parameters are being input into your application, if
your input parameters are already complex hash structures, The
set_params_hash method will set and return the serialized version of
your hashref based on the the default or custom configuration of the
hash serializer Hash::Flatten.
my $params = {
user => {
login => 'member',
password => 'abc123456'
}
};
my $serialized_params = $self->set_params_hash($params);
stash
The stash method provides a container for context/instance specific
information. The stash is particularly useful when custom validation
routines require insight into context/instance specific operations.
package MyApp::Validation;
use Validation::Class;
fld 'email' => {
validation => sub {
my $db = shift->stash->{database};
my $this = shift;
return $db->find('email' => $this->{value}) ? 0 : 1 ; # email exists
}
};
package main;
$self->stash( { database => $dbix_object } );
$self->stash( ftp => $net_ftp, database => $dbix_object );
...
validate
The validate method returns true/false depending on whether all
specified fields passed validation checks.
use MyApp::Validation;
my $input = MyApp::Validation->new(params => $params);
# validate specific fields
unless ($input->validate('field1','field2')){
return $input->errors_to_string;
}
# validate fields based on a regex pattern
unless ($input->validate(qr/^field(\d+)?/)){
return $input->errors_to_string;
}
# validate existing parameters, if no parameters exist,
# validate all fields ... which will return true unless field(s) exist
# with a required directive
unless ($input->validate()){
return $input->errors_to_string;
}
# validate all fields period, obviously
unless ($input->validate(keys %{$input->fields})){
return $input->errors_to_string;
}
# validate specific parameters (by name) after mapping them to other fields
my $parameter_map = {
user => 'hey_im_not_named_login',
pass => 'password_is_that_really_you'
};
unless ($input->validate($parameter_map)){
return $input->errors_to_string;
}
Another cool trick the validate() method can perform is the ability to
temporarily alter whether a field is required or not during run-time.
This functionality is often referred to as the *toggle* function.
This method is important when you define a field (or two or three) as
required or non and want to change that per validation. This is done by
calling the validate() method with a list of fields to be validated and
prefixing the target fields with a plus or minus as follows:
use MyApp::Validation;
my $input = MyApp::Validation->new(params => $params);
# validate specific fields, force name, email and phone to be required
# regardless of the field definitions directives ... and force the age, sex
# and birthday to be optional
my @spec = qw(+name +email +phone -age -sex -birthday);
unless ($input->validate(@spec)){
return $input->errors_to_string;
}
validate_profile
The validate_profile method executes a stored validation profile, it
requires a profile name and can be passed additional parameters which
get forwarded into the profile routine in the order received.
unless ($self->validate_profile('password_change')) {
die $self->errors_to_string;
}
unless ($self->validate_profile('email_change', $dbi_handle)) {
die $self->errors_to_string;
}
AUTHOR
Al Newkirk
COPYRIGHT AND LICENSE
This software is copyright (c) 2011 by awncorp.
This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.