A fast, extensible & stand-alone PHP input validation class that allows you to validate any data
Latest commit 6092cd0 Aug 30, 2016 @filisko filisko committed on GitHub Merge pull request #157 from eko3alpha/master
Feature: Add filter to convert MS Word special characters to web safe characters


Getting started

GUMP is a standalone PHP data validation and filtering class that makes validating any data easy and painless without the reliance on a framework.

Follow along on the project board: http://d.monsterboards.co/project/LSCPVmHUxQ-gump

There are 2 ways to install GUMP

Install Manually
  1. Download GUMP
  2. Unzip it and copy the directory into your PHP project directory.

Include it in your project:

require "gump.class.php";

$is_valid = GUMP::is_valid($_POST, array(
    'username' => 'required|alpha_numeric',
    'password' => 'required|max_len,100|min_len,6'

if($is_valid === true) {
    // continue
} else {
Install with composer

Add the following to your composer.json file:

    "require": {
        "wixel/gump": "dev-master"

Then open your terminal in your project directory and run:

composer install

Available Methods

// Shorthand validation
is_valid(array $data, array $rules)

// Get or set the validation rules
validation_rules(array $rules);

// Get or set the filtering rules
filter_rules(array $rules);

// Runs the filter and validation routines
run(array $data);

// Strips and encodes unwanted characters
xss_clean(array $data);

// Sanitizes data and converts strings to UTF-8 (if available),
// optionally according to the provided field whitelist
sanitize(array $input, $whitelist = NULL);

// Validates input data according to the provided ruleset (see example)
validate(array $input, array $ruleset);

// Filters input data according to the provided filterset (see example)
filter(array $input, array $filterset);

// Returns human readable error text in an array or string
get_readable_errors($convert_to_string = false);

// Fetch an array of validation errors indexed by the field names

// Override field names with readable ones for errors
set_field_name($field, $readable_name);

Example (Long format)

The following example is part of a registration form, the flow should be pretty standard

# Note that filters and validators are separate rule sets and method calls. There is a good reason for this.

require "gump.class.php";

$gump = new GUMP();

$_POST = $gump->sanitize($_POST); // You don't have to sanitize, but it's safest to do so.

    'username'    => 'required|alpha_numeric|max_len,100|min_len,6',
    'password'    => 'required|max_len,100|min_len,6',
    'email'       => 'required|valid_email',
    'gender'      => 'required|exact_len,1|contains,m f',
    'credit_card' => 'required|valid_cc'

    'username' => 'trim|sanitize_string',
    'password' => 'trim',
    'email'    => 'trim|sanitize_email',
    'gender'   => 'trim',
    'bio'      => 'noise_words'

$validated_data = $gump->run($_POST);

if($validated_data === false) {
    echo $gump->get_readable_errors(true);
} else {
    print_r($validated_data); // validation successful

Example (Short format)

The short format is an alternative way to run the validation.

$data = array(
    'street' => '6 Avondans Road'

$validated = GUMP::is_valid($data, array(
    'street' => 'required|street_address'

if($validated === true) {
    echo "Valid Street Address!";
} else {

Match data-keys against rules-keys

We can check if there is a rule specified for every data-key, by adding an extra parameter to the run method.

$gump->run($_POST, true);

If it doesn't match the output will be:

There is no validation rule for <span class=\"$field_class\">$field</span>

Return Values

run() returns one of two types:

ARRAY containing the successfully validated and filtered data when the validation is successful

BOOLEAN False when the validation has failed

validate() returns one of two types:

ARRAY containing key names and validator names when data does not pass the validation.

You can use this array along with your language helpers to determine what error message to show.

BOOLEAN value of TRUE if the validation was successful.

filter() returns the exact array structure that was parsed as the $input parameter, the only difference would be the filtered data.

Available Validators

  • required Ensures the specified key value exists and is not empty
  • valid_email Checks for a valid email address
  • max_len,n Checks key value length, makes sure it's not longer than the specified length. n = length parameter.
  • min_len,n Checks key value length, makes sure it's not shorter than the specified length. n = length parameter.
  • exact_len,n Ensures that the key value length precisely matches the specified length. n = length parameter.
  • alpha Ensure only alpha characters are present in the key value (a-z, A-Z)
  • alpha_numeric Ensure only alpha-numeric characters are present in the key value (a-z, A-Z, 0-9)
  • alpha_dash Ensure only alpha-numeric characters + dashes and underscores are present in the key value (a-z, A-Z, 0-9, _-)
  • alpha_space Ensure only alpha-numeric characters + spaces are present in the key value (a-z, A-Z, 0-9, \s)
  • numeric Ensure only numeric key values
  • integer Ensure only integer key values
  • boolean Checks for PHP accepted boolean values, returns TRUE for "1", "true", "on" and "yes"
  • float Checks for float values
  • valid_url Check for valid URL or subdomain
  • url_exists Check to see if the url exists and is accessible
  • valid_ip Check for valid generic IP address
  • valid_ipv4 Check for valid IPv4 address
  • valid_ipv6 Check for valid IPv6 address
  • valid_cc Check for a valid credit card number (Uses the MOD10 Checksum Algorithm)
  • valid_name Check for a valid format human name
  • contains,n Verify that a value is contained within the pre-defined value set
  • contains_list,n Verify that a value is contained within the pre-defined value set. The list of valid values must be provided in semicolon-separated list format (like so: value1;value2;value3;..;valuen). If a validation error occurs, the list of valid values is not revelead (this means, the error will just say the input is invalid, but it won't reveal the valid set to the user.
  • doesnt_contain_list,n Verify that a value is not contained within the pre-defined value set. Semicolon (;) separated, list not outputted. See the rule above for more info.
  • street_address Checks that the provided string is a likely street address. 1 number, 1 or more space, 1 or more letters
  • iban Check for a valid IBAN
  • min_numeric Determine if the provided numeric value is higher or equal to a specific value
  • max_numeric Determine if the provided numeric value is lower or equal to a specific value
  • date Determine if the provided input is a valid date (ISO 8601)
  • starts Ensures the value starts with a certain character / set of character
  • phone_number Validate phone numbers that match the following examples: 555-555-5555 , 5555425555, 555 555 5555, 1(519) 555-4444, 1 (519) 555-4422, 1-555-555-5555
  • regex You can pass a custom regex using the following format: 'regex,/your-regex/'
  • valid_json_string validate string to check if it's a valid json format

Available Filters

Filters can be any PHP function that returns a string. You don't need to create your own if a PHP function exists that does what you want the filter to do.

  • sanitize_string Remove script tags and encode HTML entities, similar to GUMP::xss_clean();
  • urlencode Encode url entities
  • htmlencode Encode HTML entities
  • sanitize_email Remove illegal characters from email addresses
  • sanitize_numbers Remove any non-numeric characters
  • sanitize_floats Remove any non-float characters
  • trim Remove spaces from the beginning and end of strings
  • base64_encode Base64 encode the input
  • base64_decode Base64 decode the input
  • sha1 Encrypt the input with the secure sha1 algorithm
  • md5 MD5 encode the input
  • noise_words Remove noise words from string
  • json_encode Create a json representation of the input
  • json_decode Decode a json string
  • rmpunctuation Remove all known punctuation characters from a string
  • basic_tags Remove all layout orientated HTML tags from text. Leaving only basic tags
  • whole_number Ensure that the provided numeric value is represented as a whole number
  • ms_word_characters Converts MS Word special characters [“”‘’–…] to web safe characters

Creating your own validators and filters

Adding custom validators and filters is made easy by using callback functions.


   Create a custom validation rule named "is_object".
   The callback receives 3 arguments:
   The field to validate, the values being validated, and any parameters used in the validation rule.
   It should return a boolean value indicating whether the value is valid.
GUMP::add_validator("is_object", function($field, $input, $param = NULL) {
    return is_object($input[$field]);

   Create a custom filter named "upper".
   The callback function receives two arguments:
   The value to filter, and any parameters used in the filter rule. It should returned the filtered value.
GUMP::add_filter("upper", function($value, $params = NULL) {
    return strtoupper($value);

Alternately, you can simply create your own class that extends the GUMP class.


class MyClass extends GUMP
    public function filter_myfilter($value, $param = NULL)

    public function validate_myvalidator($field, $input, $param = NULL)

} // EOC

$validator = new MyClass();

$validated = $validator->validate($_POST, $rules);

Please see examples/custom_validator.php for further information.

Remember to create a public methods with the correct parameter types and parameter counts.

  • For filter methods, prepend the method name with "filter_".
  • For validator methods, prepend the method name with "validate_".

Set Custom Field Names

You can easily override your form field names for improved readability in errors using the GUMP::set_field_name($field, $readable_name) method as follows:

$data = array(
    'str' => null

$rules = array(
    'str' => 'required'

GUMP::set_field_name("str", "Street");

$validated = GUMP::is_valid($data, $rules);

if($validated === true) {
    echo "Valid Street Address\n";
} else {

validating file fields

require "gump.class.php";

$is_valid = GUMP::is_valid(array_merge($_POST,$_FILES), array(
    'title' => 'required|alpha_numeric',
    'image' => 'required_file|extension,png;jpg'

if($is_valid === true) {
    // continue
} else {

Running the examples:

  1. Open up your terminal
  2. cd [GUMP DIRECTORY/examples]
  3. php [file].php

The output will depend on the input data.



  • A currency validator
  • A country validator
  • Location co-ordinates validator
  • HTML validator
  • Language validation ... determine if a piece of text is a specified language
  • Validate a spam domain or IP.
  • Validate a spam email address
  • Validate spam text with askimet or something similar
  • Improve documentation
  • More examples
  • W3C validation filter?
  • A filter that integrates with an HTML tidy service?: http://infohound.net/tidy/
  • Add a twitter & facebook profile url validator: http://stackoverflow.com/questions/2845243/check-if-twitter-username-exists
  • Add more logical examples - log in form, profile update form, blog post form, etc etc.
  • Add validators to allow checking the PHP $_FILES array.
  • Allow a validator that can check for existing files on the host machine
  • Add an 'is empty' validator check
  • Check that arrays have a positive count (if type is array)
  • A secure password validator