Validation

Validation

The validator class is a simple, convenient facility for validating data and retrieving validation error messages via the Validator class. It is useful when processing form data submitted by the end user.

When working with models, October CMS ships with a useful Validation Trait that implements the Validator class and supports the same rule definitions.

Below is a list of all available validation rules:

# Basic Usage

In most cases you should first capture the user input and pass it to the make method (first argument) and include the validation rules that should be applied to the data (second argument). In the following example, we capture the postback user input with the post() helper function.

$data = post();

$validator = Validator::make($data, [
    'name' => 'required|min:5'
]);

Multiple rules may be delimited using either a "pipe" character, or as separate elements of an array.

$validator = Validator::make($data, [
    'name' => ['required', 'min:5']
]);

To validate multiple fields, simply add them to the array.

$data = [
    'name' => 'Joe',
    'password' => 'lamepassword',
    'email' => 'email@example.tld'
];

$validator = Validator::make($data, [
    'name' => 'required',
    'password' => 'required|min:8',
    'email' => 'required|email|unique:users'
]);

# Checking the Validation Results

Once a Validator instance has been created, the fails (or passes) method may be used to perform the validation.

if ($validator->fails()) {
    // The given data did not pass validation
}

If validation has failed, you may retrieve the error messages from the validator.

$messages = $validator->messages();

You may also access an array of the failed validation rules, without messages. To do so, use the failed method:

$failed = $validator->failed();

# Validating Files

The Validator class provides several rules for validating files, such as size, mimes, and others. When validating files, you may simply pass them into the validator with your other data.

$data = files() + post();

$validator = Validator::make($data, [...]);

It is not recommended to use unfiltered input() values here since it contains GET values that can be used to potentially craft malicious links.

# Throwing a Validation Exception

In most cases, you'll be validating user input submitted using a form, and if validation fails, throwing a ValidationException is a compatible action. As a shorter way to validate the form, you can use the validate method directly.

$data = Validator::validate($data, $rules);

The validate method returns filtered user data, the attributes and values that were validated.

The above method performs the equivalent functionality as the following code. It also demonstrates how you can pass the validator instance directly to the validation exception (first argument).

$validation = Validator::make($data, $rules);

if ($validation->fails()) {
    throw new ValidationException($validation);
}

# Validating the Request

Another option is to use the Request facade to perform validation on all user input. This removes the need to supply the data so you can just supply the rules (first argument). The validate method returns filtered user data, the attributes and values that were validated.

$data = Request::validate($rules);

The return value from validate is filtered by the validation rules. If the field is not defined in the rules, it won't be included in this data.

# Working with Error Messages

After calling the messages method on a Validator instance, you will receive a Illuminate\Support\MessageBag instance, which has a variety of convenient methods for working with error messages.

# Retrieving the first error message for a field

echo $messages->first('email');

# Retrieving all error messages for a field

foreach ($messages->get('email') as $message) {
    //
}

# Retrieving all error messages for all fields

foreach ($messages->all() as $message) {
    //
}

# Determining if messages exist for a field

if ($messages->has('email')) {
    //
}

# Retrieving an error message with a format

echo $messages->first('email', '<p>:message</p>');

Note: By default, messages are formatted using Bootstrap compatible syntax.

# Retrieving all error messages with a format

foreach ($messages->all('<li>:message</li>') as $message) {
    //
}

# Error Messages & Views

Once you have performed validation, you will need an easy way to get the error messages back to your views. This is conveniently handled by October CMS. Consider the following AJAX handler as an example:

public function onRegister()
{
    $rules = [];

    $validator = Validator::make(input(), $rules);

    if ($validator->fails()) {
        return Redirect::to('register')->withErrors($validator);
    }
}

Note that when validation fails, we pass the Validator instance to the Redirect using the withErrors method. This method will flash the error messages to the session so that they are available on the next request.

October CMS will always check for errors in the session data, and automatically bind them to the view if they are available. So, it is important to note that an errors variable will always be available in all of your pages, on every request, allowing you to conveniently assume the errors variable is always defined and can be safely used. The errors variable will be an instance of MessageBag.

So, after redirection, you may utilize the automatically bound errors variable in your view:

{{ errors.first('email') }}

# Named Error Bags

If you have multiple forms on a single page, you may wish to name the MessageBag of errors. This will allow you to retrieve the error messages for a specific form. Simply pass a name as the second argument to withErrors.

return Redirect::to('register')->withErrors($validator, 'login');

You may then access the named MessageBag instance from the $errors variable:

{{ errors.login.first('email') }}

# Available Validation Rules

Below are all available validation rules and their functions.

# accepted

The field under validation must be yes, on, or 1. This is useful for validating "Terms of Service" acceptance.

# active_url

The field under validation must be a valid URL according to the checkdnsrr PHP function.

# after:date

The field under validation must be a value after a given date. The dates will be passed into the PHP strtotime function.

# alpha

The field under validation must be entirely alphabetic characters.

# alpha_dash

The field under validation may have alpha-numeric characters, as well as dashes and underscores.

# alpha_num

The field under validation must be entirely alpha-numeric characters.

# array

The field under validation must be of type array.

# before:date

The field under validation must be a value preceding the given date. The dates will be passed into the PHP strtotime function.

# between:min,max

The field under validation must have a size between the given min and max. Strings, numerics, and files are evaluated in the same fashion as the size rule.

# boolean

The field under validation must be able to be cast as a boolean. Accepted input are true, false, 1, 0, "1" and "0".

# confirmed

The field under validation must have a matching field of foo_confirmation. For example, if the field under validation is password, a matching password_confirmation field must be present in the input.

# date

The field under validation must be a valid date according to the strtotime PHP function.

# date_format:format

The field under validation must match the format defined according to the date_parse_from_format PHP function.

# different:field

The given field must be different than the field under validation.

# digits:value

The field under validation must be numeric and must have an exact length of value.

# digits_between:min,max

The field under validation must have a length between the given min and max.

# email

The field under validation must be formatted as an e-mail address.

# exists:table,column

The field under validation must exist on a given database table.

Basic usage of exists rule

'state' => 'exists:states'

Specifying a custom column name

'state' => 'exists:states,abbreviation'

You may also specify more conditions that will be added as "where" clauses to the query:

'email' => 'exists:staff,email,account_id,1'

Passing NULL as a "where" clause value will add a check for a NULL database value:

'email' => 'exists:staff,email,deleted_at,NULL'

# image

The file under validation must be an image (jpeg, png, bmp, or gif)

# in:foo,bar,...

The field under validation must be included in the given list of values.

# integer

The field under validation must have an integer value.

# ip

The field under validation must be formatted as an IP address.

# max:value

The field under validation must be less than or equal to a maximum value. Strings, numerics, and files are evaluated in the same fashion as the size rule.

# mimes:foo,bar,...

The file under validation must have a MIME type corresponding to one of the listed extensions.

# Basic usage of MIME rule

'photo' => 'mimes:jpeg,bmp,png'

# min:value

The field under validation must have a minimum value. Strings, numerics, and files are evaluated in the same fashion as the size rule.

# not_in:foo,bar,...

The field under validation must not be included in the given list of values.

# nullable

The field under validation may be null. This is particularly useful when validating primitive such as strings and integers that can contain null values.

# numeric

The field under validation must have a numeric value.

# regex:pattern

The field under validation must match the given regular expression.

Note: When using the regex pattern, it may be necessary to specify rules in an array instead of using pipe delimiters, especially if the regular expression contains a pipe character.

# required

The field under validation must be present in the input data.

# required_if:field,value,...

The field under validation must be present if the field field is equal to any value.

# required_unless:anotherfield,value,...

The field under validation must be present and not empty unless the anotherfield field is equal to any value.

# required_with:foo,bar,...

The field under validation must be present only if any of the other specified fields are present.

# required_with_all:foo,bar,...

The field under validation must be present only if all of the other specified fields are present.

# required_without:foo,bar,...

The field under validation must be present only when any of the other specified fields are not present.

# required_without_all:foo,bar,...

The field under validation must be present only when the all of the other specified fields are not present.

# same:field

The specified field value must match the field's value under validation.

# size:value

The field under validation must have a size matching the given value. For string data, value corresponds to the number of characters. For numeric data, value corresponds to a given integer value. For files, size corresponds to the file size in kilobytes.

# string:value

The field under validation must be a string type.

# timezone

The field under validation must be a valid timezone identifier according to the timezone_identifiers_list PHP function.

# unique:table,column,except,idColumn

The field under validation must be unique on a given database table. If the column option is not specified, the field name will be used.

Basic usage of unique rule.

'email' => 'unique:users'

Specifying a custom column name.

'email' => 'unique:users,email_address'

Forcing a unique rule to ignore a given ID.

'email' => 'unique:users,email_address,10'

Adding additional where clauses.

You may also specify more conditions that will be added as "where" clauses to the query:

'email' => 'unique:users,email_address,NULL,id,account_id,1'

In the rule above, only rows with an account_id of 1 would be included in the unique check.

# site_unique:table,column,except,idColumn

The field under validation must be unique within the same site context. The definition is identical to the unique rule.

'email' => 'site_unique:users'

# url

The field under validation must be formatted as an URL.

This function uses PHP's filter_var method.

# Conditionally Adding Rules

In some situations, you may wish to run validation checks against a field only if that field is present in the input array. To quickly accomplish this, add the sometimes rule to your rule list:

$v = Validator::make($data, [
    'email' => 'sometimes|required|email',
]);

In the example above, the email field will only be validated if it is present in the $data array.

# Complex Conditional Validation

Sometimes you may wish to require a given field only if another field has a greater value than 100. Or you may need two fields to have a given value only when another field is present. Adding these validation rules doesn't have to be a pain. First, create a Validator instance with your static rules that never change:

$v = Validator::make($data, [
    'email' => 'required|email',
    'games' => 'required|numeric',
]);

Let's assume our web application is for game collectors. If a game collector registers with our application and they own more than 100 games, we want them to explain why they own so many games. For example, perhaps they run a game re-sell shop, or maybe they just enjoy collecting. To conditionally add this requirement, we can use the sometimes method on the Validator instance.

$v->sometimes('reason', 'required|max:500', function($input) {
    return $input->games >= 100;
});

The first argument passed to the sometimes method is the name of the field we are conditionally validating. The second argument is the rules we want to add. If the Closure passed as the third argument returns true, the rules will be added. This method makes it a breeze to build complex conditional validations. You may even add conditional validations for several fields at once:

$v->sometimes(['reason', 'cost'], 'required', function($input) {
    return $input->games >= 100;
});

The $input parameter passed to your Closure will be an instance of Illuminate\Support\Fluent and may be used as an object to access your input and files.

# Validating Arrays

Validating array based form input fields doesn't have to be a pain. You may use "dot notation" to validate attributes within an array. For example, if the incoming HTTP request contains a photos[profile] field, you may validate it like so:

$validator = Validator::make(input(), [
    'photos.profile' => 'required|image',
]);

You may also validate each element of an array. For example, to validate that each e-mail in a given array input field is unique, you may do the following:

$validator = Validator::make(input(), [
    'person.*.email' => 'email|unique:users',
    'person.*.first_name' => 'required_with:person.*.last_name',
]);

Likewise, you may use the * character when specifying your validation messages in your language files, making it a breeze to use a single validation message for array based fields:

'custom' => [
    'person.*.email' => [
        'unique' => 'Each person must have a unique e-mail address',
    ]
],

You may also use "array notation" in your validation rules if you wish. These rules will be converted to "dot notation" automatically on validation.

$validator = Validator::make(input(), [
    'photos[profile]' => 'required|image',
    'person[][email]' => 'email|unique:users',
]);

# Custom Error Messages

If needed, you may use custom error messages for validation instead of the defaults. There are several ways to specify custom messages. The following shows how to pass custom messages to the validator instance.

$messages = [
    'required' => 'The :attribute field is required.',
];

$validator = Validator::make($input, $rules, $messages);

The :attribute placeholder will be replaced by the actual name of the field under validation. You may also utilize other placeholders in validation messages. The following shows some other validation placeholders you may encounter.

$messages = [
    'same' => 'The :attribute and :other must match.',
    'size' => 'The :attribute must be exactly :size.',
    'between' => 'The :attribute must be between :min - :max.',
    'in' => 'The :attribute must be one of the following types: :values',
];

Sometimes you may wish to specify a custom error messages only for a specific field. The following will specify a custom message for the email attribute when using the required rule.

$messages = [
    'email.required' => 'We need to know your e-mail address!',
];

# Specifying Custom Messages in Language Files

In some cases, you may wish to specify your custom messages in a language file instead of passing them directly to the Validator. To do so, add your messages to an array in the lang/xx/validation.php language file for your plugin.

return  [
    'required' => 'We need to know your e-mail address!',
    'email.required' => 'We need to know your e-mail address!',
];

Then in your call to Validator::make use the Lang:get to use your custom files.

Validator::make($formValues, $validations, Lang::get('acme.blog::validation'));

# Overriding Validation Messages Globally

The default message strings for the validator are located in the modules/system/lang/xx/validation.php file. We recommend opening this file to locate all the available messages.

The file contains an array of messages for each validation rule. There is a custom attribute for custom error messages using the "attribute.rule" naming convention, and a attributes attribute to store custom attribute names.

return [
    'required' => 'The :attribute field is required!',
    // ...

    'custom' => [
        // ...
    ],

    'attributes' => [
        // ...
    ]
];

You can modify any of these values by creating a new file in the app directory, for example, for the en locale, create a file called app/lang/system/en/validation.php. The values inside this file will override the default values and you can include just the values you want modified.

return [
    'required' => 'Sorry, we need that field (:attribute) you gave!',

    'attributes' => [
        'email' => 'email address'
    ],
];

# Custom Validation Rules

There are a variety of helpful validation rules, however, you may wish to specify some of your own. First you should decide if your rule should be registered globally, or use a local rule object.

# Globally Registered Rules

A globally registered rule can be shared throughout your application by registering it with a tag and rule class. This is typically done in the register method of a plugin registration file using the registerValidationRule helper method.

public function register()
{
    $this->registerValidationRule('uppercase', UppercaseRule::class);
}

In this instance, we have created a rule tagged uppercase and referenced our rule class where it becomes available to specify as a rule everywhere.

Validator::make($data, [
    'shoutout' => 'required|uppercase',
]);

# Defining a Global Rule Class

A global rule class represents a single reusable validation rule for your models. At a minimum, the rule class must provide a validate method that determines if the validation rule passes. You may also specify an optional message method to return a custom error message.

class UppercaseRule
{
    /**
     * validate determines if the validation rule passes.
     * @param string $attribute
     * @param mixed $value
     * @param array $params
     * @return bool
     */
    public function validate($attribute, $value, $params)
    {
        return strtoupper($value) === $value;
    }

    /**
     * message gets the validation error message.
     * @return string
     */
    public function message()
    {
        return 'The :attribute must be uppercase.';
    }
}

# Passing Arguments to Rules

Global rules can support passing arguments along with their definition. For example, a rule called betwixt may require two values. Parameters can be passed to a rule by separating with a colon (:) and each parameter is seperated by a comma (,).

$v = Validator::make($data, [
    'name' => 'betwixt:1,6',
]);

The parameters are then passed to the validate method and become available. The error message can also be processed by defining a replace method.

class BetwixtRule
{
    /**
     * validate between start and end parameters.
     */
    public function validate($attribute, $value, $params)
    {
        [$start, $end] = $params;

        return strlen($value) > $start && strlen($value) < $end;
    }

    /**
     * message gets the validation error message.
     * @return string
     */
    public function message()
    {
        return 'The :attribute must be between :start and :end.';
    }

    /**
     * replace defines custom placeholder replacements.
     * @return string
     */
    public function replace($message, $attribute, $rule, $params)
    {
        [$start, $end] = $params;

        $message = str_replace(':start', $start, $message);

        $message = str_replace(':end', $end, $message);

        return $message;
    }
}

# Local Rule Objects

The Laravel documentation on rule objects (opens new window) describes in more detail how to define a rule class. Specifically, the rule must implement the Illuminate\Contracts\Validation\Rule contract which requires a passes method to be defined.

class LowercaseRule implements \Illuminate\Contracts\Validation\Rule
{
    /**
     * passes checks if the rule is successful
     * @param  string  $attribute
     * @param  mixed  $value
     * @return bool
     */
    public function passes($attribute, $value)
    {
        return strtolower($value) === $value;
    }

    /**
     * message gets the validation error message.
     * @return string
     */
    public function message()
    {
        return 'The :attribute must be lowercase.';
    }
}

Once a rule is defined, it can be passed as an insatance to the Validator service.

$v = Validator::make($data, [
    'name' => ['required', new LowercaseRule],
]);

You may also implement the rule object in models using the beforeValidate method override.

public function beforeValidate()
{
    $this->rules['name'] = ['required', new LowercaseRule];
}

# See Also