CakePHP Form Validation only on Entering Data

Question

I am trying to Upload a photo for one of the models and when i am going to the edit mode. It still asks me to upload the photo when the user only wants to edit the text rela

Answer 1

uploadError expects an upload

The code for uploadError expects an upload:

public static function uploadError($check) {
    if (is_array($check) && isset($check['error'])) {
        $check = $check['error'];
    }

    return (int)$check === UPLOAD_ERR_OK;
}

If there is no file uploaded the error will not contain that value - it'll be UPLOAD_ERR_NO_FILE.

File uploads are never empty

Putting 'allowEmpty' => true, in the rule definition won't have any effect as the value, if present, will never be empty - it's always of the form:

array(
    ...
    'error' => int
)

As such it's best to remove allowEmpty from all the file-upload validation rules.

Use beforeValidate

Instead of dealing with the validation rules, you can instead use beforeValidate to simply remove the file upload data before the validation check is made:

public function beforeValidate() {
    if (
        isset($this->data[$this->alias]['display_photo']) &&
        $this->data[$this->alias]['display_photo']['error'] === UPLOAD_ERR_NO_FILE
    ) {
        unset($this->data[$this->alias['display_photo']);
    }
    return parent::beforeValidate();
}

In this way the validation rules for display_photo are skipped entirely if there is no upload to process.