NAME Validation::Class - Low-Fat Full-Flavored Data Modeling and Validation Framework VERSION version 5.64 SYNOPSIS package MyVal::User; use Validation::Class; # rules mixin mxn basic => { required => 1, max_length => 255, filters => [qw/trim strip/] }; # attr(s) w/rules fld id => { mixin => 'basic', max_length => 11, required => 0 }; fld name => { mixin => 'basic', min_length => 2 }; fld email => { mixin => 'basic', min_length => 3 }; fld login => { mixin => 'basic', min_length => 5 }; fld password => { mixin => 'basic', min_length => 5, min_symbols => 1 }; has attitude => 1; # just an attr # self-validating method mth create => { input => [qw/name email login password/], output => ['+id'], using => sub { my ($self, @args) = @_; # make sure to set id for output validation } }; package main; my $user = MyVal::User->new(name => '...', email => '...'); unless ($user->create) { # did you forget your login and pass? } 1; Validation::Class takes a different approach towards data validation, it centralizes data validation rules to ensure consistency through DRY (dont-repeat-yourself) code. use MyApp; my $params = { 'user.login' => '...', 'user.pass' => '...' }; my $app = MyApp->new(params => $params); my $user = $app->class('user'); # instantiated MyApp::User object unless ($user->validate('login', 'pass')){ # do something with ... $input->errors; } DESCRIPTION Validation::Class is much more than a simple data validation framework, in-fact it is more of a data modeling framework and can be used as an alternative to minimalistic object systems such as Moo, Mo, etc. Validation::Class aims to provide the building blocks for easily defining self-validating data models. When fields (attributes with validation rules) are defined, accessors are automatically generated to make getting and setting their values much easier. Methods can be defined using the method keyword which can make the routine self-validating, checking the defined input requirements against existing validation rules before executing the routine gaining consistency and security. KEYWORDS attribute The attribute keyword (or has) creates a class attribute. package MyApp::User; use Validate::Class; has 'attitude' => sub { return $self->bothered ? 1 : 0 }; 1; The attribute keyword takes two arguments, the attribute name and a constant or coderef that will be used as its default value. build The build keyword (or bld) registers a coderef to be run at instantiation much in the same way the common BUILD routine is used in modern-day OO systems. package MyApp::User; use Validation::Class; build sub { my $self = shift; # ... do something }; The build keyword takes one argument, a coderef which is passed the instantiated class object. directive The directive keyword (or dir) creates custom validator directives to be used in your field definitions. It is a means of extending the pre-existing directives table before runtime and is ideal for creating custom directive extension packages to be used in all your classes. package MyApp::Directives; use Validation::Class; use Data::Validate::Email; directive 'is_email' => sub { my ($dir, $value, $field, $self) = @_; my $validator = Data::Validate::Email->new; unless ($validator->is_email($value)) { my $handle = $field->{label} || $field->{name}; $self->error($field, "$handle must be a valid email address"); return 0; } return 1; }; package MyApp::User; use Validate::Class; use MyApp::Directives; field 'email' => { is_email => 1, ... }; 1; The directive keyword takes two arguments, the name of the directive and a coderef which will be used to validate the associated field. The coderef is passed four ordered parameters, the value of directive, the value of the field (parameter value), the field object (hashref), and the instantiated class object. The validator MUST return true or false. field The field keyword (or fld) creates an attribute with validation rules for reuse in code. The field keyword may also correspond with the parameter name expected to be passed to your validation class. package MyApp::User; 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 known as directives. Protip: Fields are used to validate constant and array data, not hashrefs and objects. Don't try to use fields like attributes (use the has keyword instead). filter The filter keyword (or flt) creates custom filters to be used in your field definitions. It is a means of extending the pre-existing filters table before runtime and is ideal for creating custom directive extension packages to be used in all your classes. package MyApp::Directives; use Validation::Class; filter 'flatten' => sub { $_[0] =~ s/[\t\r\n]+/ /g; $_[0] # return }; package MyApp::User; use Validate::Class; use MyApp::Directives; field 'description' => { filters => ['trim', 'flatten'], ... }; 1; The filter keyword takes two arguments, the name of the filter and a coderef which will be used to filter the value the associated field. The coderef is passed the value of the field and that value MUST be operated on directly. The coderef should also return the transformed value. load The load keyword (or set), which can also be used as a method, provides options for further configuring the calling class. package MyApp; use Validation::Class; # load specific child class load { ... }; 1; The "load.class" option, can be a constant or arrayref, will require other classes specifically and add them to the relationship map for convenient access through the class() method. Existing parameters and configuration options are passed to the child class' constructor. All attributes can be easily overwritten using the attribute's accessors on the child class. package MyApp; use Validation::Class; # load specific child class load { class => 'MyApp::Relative' }; package main; my $app = MyApp->new; my $rel = $app->class('relative'); # instantiated MyApp::Relative object my $rel = $app->class('MyApp::Relative'); # alternatively 1; The "load.classes" option, can be a constant or arrayref, uses Module::Find to load all child classes (in-all-subdirectories) for convenient access through the class() method. Existing parameters and configuration options are passed to the child class' constructor. All attributes can be easily overwritten using the attribute's accessors on the child class. package MyApp; use Validation::Class; # load specific child class load { classes => 1 }; package main; my $app = MyApp->new; my $rel = $app->class('relative'); # instantiated MyApp::Relative object my $rel = $app->class('MyApp::Relative'); # alternatively my $rel = $app->class('data_source'); # MyApp::DataSource my $rel = $app->class('data_source-first'); # MyApp::DataSource::First 1; The "load.plugins" option is used to load plugins that support Validation::Class. A Validation::Class plugin is little more than a class that implements a "new" method that extends the associated validation class object. As usual, an official Validation::Class plugin can be referred to using shorthand while custom plugins are called by prefixing a plus symbol to the fully-qualified plugin name. Learn more about plugins at Validation::Class::Cookbook. package MyVal; load { plugins => [ 'CPANPlugin', # Validation::Class::Plugin::CPANPlugin '+MyVal::Plugin' ] }; 1; method The method keyword (or mth) is used to create an auto-validating method. Similar to method signatures, an auto-validating method can leverage pre-existing validation rules and profiles to ensure a method has the required data necessary to proceed. package MyApp::User; use Validation::Class; method 'register' => { input => ['name', '+email', 'login', '+password'], output => ['+id'], # optional output validation using => sub { my ($self, @args) = @_; # .... do something registrationy $self->id(...); # set the ID field for output validation return $self; } }; package main; my $user = MyApp::User->new(params => $params); if ($user->register) { ... } 1; The method keyword takes two arguments, the name of the method to be created and a hashref of required key/value pairs. The hashref must have an "input" variable whose value is either an arrayref of fields to be validated, or a constant value which matches a validation profile name. The hashref must also have a "using" variable whose value is a coderef which will be executed upon successfully validating the input. Whether and what the method returns is yours to decide. Optionally the required hashref can have an "output" variable whose value is either an arrayref of fields to be validated, or a constant value which matches a validation profile name which will be used to perform data validation after the coderef has been executed. Please note that output validation failure will cause the program to die, the premise behind this decision is based on the assumption that given successfully validated input a routine's output should be predictable and if an error occurs it is most-likely a program error as opposed to a user error. See the ignore_failure and report_failure switch to control how method input validation failures are handled. mixin The mixin keyword (or mxn) creates a validation rules template that can be applied to any field using the mixin directive. Mixin directives are processed first so existing field directives will override the mixed-in directives. package MyApp::User; use Validation::Class; mixin 'constrain' => { required => 1, min_length => 1, max_length => 255, ... }; # e.g. field 'login' => { mixin => 'constrain', ... }; The mixin keyword takes two arguments, the mixin name and a hashref of key/values pairs known as directives. profile 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. package MyApp::User; use Validation::Class; profile 'signup' => sub { my ($self, @args) = @_; return $self->validate(qw( +name +email +email_confirmation -login +password +password_confirmation )); }; package main; my $user = MyApp::User->new(params => $params); unless ($user->validate_profile('signup')) { die $user->errors_to_string; } The profile keyword takes two arguments, a profile name and coderef which will be used to execute a sequence of actions for validation purposes. METHODS new The new method, exported into the calling namespace automatically, should NOT be tampered with. The new method performs a series of actions (magic) required for the class to function properly. See the build keyword for hooking into the instantiation process. package MyApp; use Validation::Class; package main; my $app = MyApp->new; ... ATTRIBUTES, METHODS, AND MORE This class encapsulates the functionality used to manipulate the environment of the calling class. The engine-class is the role that provides all of the data validation functionality, please see Validation::Class::Engine for more information on specific methods, and attributes. 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.