validators

Aeria's field validation

Aeria validates fields while editing the frontend, calling our validation API, and while saving the fields in the backend.

Stock validators

Aeria provides a simple way to validate the edited fields. By default, two validators are integrated in Aeria:

• "isEmail" checks if the inserted value is a valid email, using PHP's FILTER_VALIDATE_EMAIL
• "isShort" checks if the inserted string is too short (length<4)

Extending Aeria's validators

We obviously thought you may need new validators, so here are two dummy-proof ways of creating new validators.

Creating a RegEx validator

Let's say we want to validate our book author by checking if there are no special characters in his name. The regular expression we need is something like this: /^\w*$/. Now, we only need to extend AbstractRegExValidator with our AuthorValidator.

RegEx validators need 3 properties:

• $_key is our validator name. We're gonna use isAuthor.
• $_message is the error message displayed when this validator is not satisfied.
• $_validator is our RegEx. Don't forget PHP's RegExs delimiter /.

Now we're able to create our validator class in functions.php.

if (function_exists('aeria')) {
  class AuthorValidator extends Aeria\Validator\Types\RegEx\AbstractRegExValidator
  {
    protected static $_key="isAuthor";
    protected static $_message="Please, insert a valid author.";
    protected static $_validator="/^\w*$/";
  }
  aeria('validator')->registerValidatorClass(AuthorValidator::class);
}

After declaring the class, we need to register the validator in Aeria by calling registerValidatorClass.

Now that the validator is registered, we just need to add it to the author field.

{
  "type": "text",
  "id": "author-name",
  "label": "Author name",
  "description": "Insert the book's author name here.",
  "size": "half",
  "placeholder": "Author",
  "validators": "isAuthor",
  "required": true
}

Creating a callable validator

Sometimes your validation cannot just be a simple RegEx. Aeria offers you the possibility to declare validators with callable methods inside them.

Let's say we now want to check if the book's cover image exists. A RegEx cannot obviously do this.

We need to extend Aeria\Validator\Types\Callables\AbstractValidator with our BookCoverValidator.

Like the RegEx validator, a callable validator needs:

• a $_key to access the validator, let's say, "isBookCover".
• an error $_message to display the user.
• a getValidator method returning a function.

The function returned by getValidator has one argument, $field, and returns an array composed of:

• "status" which may be
  • false if the field is ok.
  • true if the field is not valid.
• "message" just in case "status" is true, containing the error message.

Now we're able to create our validator class in functions.php.

if (function_exists('aeria')) {
  class BookCoverValidator extends Aeria\Validator\Types\Callables\AbstractValidator
  {
      protected static $_key="isBookCover";
      protected static $_message="Please insert a valid book cover.";
  
      public static function getValidator(){
          return function ($photoID)
          {
              if (wp_get_attachment_image($photoID) != null)
                return ["status" => false];
              else
                return ["status" => true,"message" => static::$_message];
          };
      }
  }
  aeria('validator')->registerValidatorClass(BookCoverValidator::class);
}

After declaring the class, we need to register the validator in Aeria by calling registerValidatorClass.

Now that the validator is registered, we just need to add it to the book cover field.

{
  "type": "picture",
  "id": "book-cover",
  "label": "Book cover",
  "description": "Insert the book's cover",
  "size": "full",
  "required": true,
  "ctaLabel": "Insert cover",
  "validators": "isBookCover"
}

Our validator is now up and running.

Validation API

You may want to validate your fields before saving them in the backend. We exposed a validation API that does just that.

Validating with a validators list

To validate a field with a validators list, you just need two parameters:

• field is the value of the field.
• validators contains all the validators, separated by a |.

The response is an array containing

• if the validation was not passed, a "message" array containing all the error messages.
• a "status" boolean, false if the field is valid, true if not.
• a "value" string, containing the checked value.

The API can be accessed on the path http://example.com/wp-json/aeria/validate.

An example call to this validation API may be:

http://example.com/wp-json/aeria/validate?field=johnsmithatexample.com&validators=isEmail|isShort, which would return:

{
    "message": [
        "Please insert a valid email. "
    ],
    "value": "johnsmithatexample.com",
    "status": true
}

Validating with a field's ID

Sometimes you just don't wanna cope with validators lists. Know the field's ID? That's all you need.

You can use this validator at http://example.com/wp-json/aeria/validate-by-id, with the parameters:

• field_id is the value of the field's full ID, containing the metabox ID. This is the key you can see in the database.
• value is the value you want to validate.

The response is equal to the one above, so an array containing:

• if the validation was not passed, a "message" array containing all the error messages.
• a "status" boolean, false if the field is valid, true if not.
• a "value" string, containing the checked value.

An example call to this validation API may be:

http://example.com/wp-json/aeria/validate-by-id?field_id=metaexample-input-text-email&value=aeria%example,com, which would return:

{
    "message": [
        "Please insert a valid email. "
    ],
    "value": "aeria%example,com",
    "status": true
}

A valid email, would instead return:

{
    "message": [],
    "value": "aeria@example.com",
    "status": false
}