Validate that a Value Exists
Ensure that a value entered in Form A has been previously submitted on Form B. This is useful if you’re generating a reference number of some sort on Form B and would like the user to enter it on Form A.
Instructions
See “Where do I put snippets?” in our documentation for installation instructions.
Code
Filename: gw-validate-that-a-value-exists.php
<?php
/**
* Gravity Wiz // Gravity Forms // Validate that a Value Exists
*
* Ensure that a value entered in Form A has been previously submitted on Form B. This is useful if you're generating a reference number of some sort
* on Form B and would like the user to enter it on Form A.
*
* @version 1.10
* @author David Smith <david@gravitywiz.com>
* @license GPL-2.0+
* @link https://gravitywiz.com/require-existing-value-submission-gravity-forms/
*/
class GW_Value_Exists_Validation {
protected static $is_script_output = false;
private $_args = array();
public function __construct( $args = array() ) {
// set our default arguments, parse against the provided arguments, and store for use throughout the class
$this->_args = wp_parse_args( $args, array(
'target_form_id' => false,
'target_field_id' => false,
'source_form_id' => false,
'source_field_id' => false,
'validation_message' => __( 'Please enter a valid value.' ),
'field_map' => array(),
'disable_ajax_validation' => false,
'validate_blank_values' => true,
) );
// Map source and target fields to field map if field map is not set.
if ( empty( $this->_args['field_map'] ) ) {
$this->_args['field_map'] = array( $this->_args['source_field_id'] => $this->_args['target_field_id'] );
}
// do version check in the init to make sure if GF is going to be loaded, it is already loaded
add_action( 'init', array( $this, 'init' ) );
}
public function init() {
// make sure we're running the required minimum version of Gravity Forms
if ( ! property_exists( 'GFCommon', 'version' ) || ! version_compare( GFCommon::$version, '1.8', '>=' ) ) {
return;
}
add_filter( 'gform_validation', array( $this, 'validation' ) );
if ( ! $this->_args['disable_ajax_validation'] ) {
add_action( 'gform_enqueue_scripts', array( $this, 'enqueue_form_script' ) );
add_filter( 'gform_pre_render', array( $this, 'load_form_script' ), 10, 2 );
add_action( 'gform_register_init_scripts', array( $this, 'add_init_script' ) );
add_action( 'wp_ajax_gwvev_does_value_exist', array( $this, 'ajax_does_value_exist' ) );
add_action( 'wp_ajax_nopriv_gwvev_does_value_exist', array( $this, 'ajax_does_value_exist' ) );
}
}
public function enqueue_form_script( $form ) {
if ( $this->is_applicable_form( $form ) ) {
wp_enqueue_script( 'gform_gravityforms' );
}
return $form;
}
public function validation( $result ) {
if ( ! $this->is_applicable_form( $result['form'] ) ) {
return $result;
}
foreach ( $result['form']['fields'] as &$field ) {
if ( $this->is_applicable_field( $field ) && ! GFFormsModel::is_field_hidden( $result['form'], $field, array() ) ) {
if ( ! $this->do_values_exists( $this->get_values(), $this->_args['source_form_id'] ) ) {
$field['failed_validation'] = true;
$field['validation_message'] = $this->_args['validation_message'];
$result['is_valid'] = false;
}
}
}
return $result;
}
public function ajax_does_value_exist() {
if ( ! wp_verify_nonce( rgpost( 'nonce' ), 'gwvev_does_value_exist' ) ) {
die( __( 'Invalid nonce.' ) );
}
$form_id = rgpost( 'form_id' );
$values = rgpost( 'values' );
$entries = $this->get_matching_entry( $values, $form_id );
echo json_encode( array(
'doesValueExist' => ! empty( $entries ),
'entries' => $entries,
) );
die();
}
public function does_value_exist( $value, $form_id, $field_id ) {
$entries = $this->get_matching_entry( array( $field_id => $value ), $form_id );
return count( $entries ) > 0;
}
public function do_values_exists( $values, $form_id ) {
$entries = $this->get_matching_entry( $values, $form_id );
return $entries && count( $entries ) > 0;
}
public function get_matching_entry( $values, $form_id ) {
$field_filters = array();
foreach ( $values as $field_id => $value ) {
$field_filters[] = array(
'key' => $field_id,
'value' => $value,
);
}
$args = apply_filters( 'gwvev_get_entries_args', array(
$form_id,
array(
'status' => 'active',
'field_filters' => $field_filters,
),
) );
$entries = GFAPI::get_entries( $args[0], $args[1] );
return reset( $entries );
}
public function get_field_map() {
if ( ! empty( $this->_args['field_map'] ) ) {
$field_map = $this->_args['field_map'];
} else {
$field_map = array( $this->_args['target_field_id'] => $this->_args['source_field_id'] );
}
return $field_map;
}
public function get_values() {
$field_map = $this->get_field_map();
$values = array();
foreach ( $field_map as $source_field_id => $target_field_id ) {
$value = rgpost( 'input_' . $target_field_id );
if ( ! rgblank( $value ) || $this->_args['validate_blank_values'] ) {
$values[ $source_field_id ] = $value;
}
}
return $values;
}
public function load_form_script( $form, $is_ajax_enabled ) {
// Do not output main script if AJAX is enabled
if ( ! $is_ajax_enabled && $this->is_applicable_form( $form ) && ! self::$is_script_output && ! $this->is_ajax_submission( $form['id'], $is_ajax_enabled ) ) {
add_action( 'wp_footer', array( $this, 'output_script' ) );
add_action( 'gform_preview_footer', array( $this, 'output_script' ) );
}
return $form;
}
public function output_script() {
?>
<script type="text/javascript">
( function( $ ) {
window.GWValueExistsValidation = function( args ) {
var self = this;
// copy all args to current object: (list expected props)
for( prop in args ) {
if( args.hasOwnProperty( prop ) ) {
self[ prop ] = args[ prop ];
}
}
self.init = function() {
self.$elems().on( 'change', function() {
var inputId = gf_get_input_id_by_html_id( $( this ).attr( 'id' ) );
for( var sourceFieldId in self.fieldMap ) {
if( self.fieldMap.hasOwnProperty( sourceFieldId ) && sourceFieldId == inputId ) {
break;
}
}
self.doesValueExist( $( this ) )
} );
};
self.getAllValues = function() {
var values = {};
self.$elems().each( function() {
var inputId = gf_get_input_id_by_html_id( $( this ).attr( 'id' ) );
for( var sourceFieldId in self.fieldMap ) {
if( self.fieldMap.hasOwnProperty( sourceFieldId ) && sourceFieldId == inputId ) {
break;
}
}
values[ sourceFieldId ? sourceFieldId : inputId ] = $( this ).val();
} );
return values;
}
self.doAllFieldsHaveValue = function() {
var values = Object.values( self.getAllValues() );
return values.length === values.filter( Boolean ).length;
}
self.doesValueExist = function( $elem ) {
if ( ! self.doAllFieldsHaveValue() ) {
self.removeIndicators();
return;
}
self.removeIndicators();
var spinner = new self.spinner( $elem, false, 'position:relative;top:2px;left:-25px;' ),
$buttons = $( '.gform_button' );
$buttons.prop( 'disabled', true );
self.$elems().prop( 'disabled', true );
$.post( self.ajaxUrl, {
nonce: self.nonce,
action: 'gwvev_does_value_exist',
values: self.getAllValues(),
form_id: self.sourceFormId
}, function( response ) {
self.$elems().prop( 'disabled', false );
$buttons.prop( 'disabled', false );
spinner.destroy();
if( ! response ) {
return;
}
response = $.parseJSON( response );
if( response.doesValueExist ) {
self.addIndicators( 'gwvev-response-success', '✔' );
} else {
self.addIndicators( 'gwvev-response-error', '✘' )
}
gform.doAction( 'gwvev_post_ajax_validation', self, response );
} );
};
self.$elems = function() {
return $( self.selectors.join( ', ' ) );
}
self.getIndicatorId = function( inputId ) {
return 'response_{0}_{1}'.gformFormat( self.targetFormId, inputId );
}
self.getIndicatorTemplate = function() {
return '<span id="{0}" class="gwvev-response {1}">{2}</span>';
}
self.removeIndicators = function() {
self.$elems().each( function() {
var inputId = gf_get_input_id_by_html_id( $( this ).attr( 'id' ) );
self.removeIndicator( inputId );
} );
}
self.removeIndicator = function( inputId ) {
$( '#' + self.getIndicatorId( inputId ) ).remove();
}
self.addIndicators = function( cssClass, icon ) {
self.$elems().each( function() {
var inputId = gf_get_input_id_by_html_id( $( this ).attr( 'id' ) );
self.addIndicator( $( this ), inputId, cssClass, icon );
} );
}
self.addIndicator = function( $elem, inputId, cssClass, icon ) {
$elem.after( self.getIndicatorTemplate().gformFormat( self.getIndicatorId( inputId ), cssClass, icon ) );
}
self.spinner = function( elem, imageSrc, inlineStyles ) {
imageSrc = typeof imageSrc == 'undefined' || ! imageSrc ? window.gf_global.spinnerUrl : imageSrc;
inlineStyles = typeof inlineStyles != 'undefined' ? inlineStyles : '';
this.elem = elem;
this.image = '<img class="gfspinner" src="' + imageSrc + '" style="' + inlineStyles + '" />';
this.init = function() {
this.spinner = jQuery(this.image);
jQuery(this.elem).after(this.spinner);
return this;
};
this.destroy = function() {
jQuery(this.spinner).remove();
};
return this.init();
};
self.init();
}
} )( jQuery );
</script>
<?php
self::$is_script_output = true;
}
public function add_init_script( $form ) {
if ( ! $this->is_applicable_form( $form ) ) {
return;
}
$args = array(
'ajaxUrl' => admin_url( 'admin-ajax.php' ),
'nonce' => wp_create_nonce( 'gwvev_does_value_exist' ),
'targetFormId' => $this->_args['target_form_id'],
'sourceFormId' => $this->_args['source_form_id'],
'selectors' => $this->get_selectors( $form ),
'fieldMap' => $this->get_field_map(),
'gfBaseUrl' => GFCommon::get_base_url(),
);
$script = 'new GWValueExistsValidation( ' . json_encode( $args ) . ' );';
$slug = implode( '_', array( 'gw_value_exists_validation', $this->_args['target_form_id'], $this->_args['target_field_id'] ) );
GFFormDisplay::add_init_script( $this->_args['target_form_id'], $slug, GFFormDisplay::ON_PAGE_RENDER, $script );
}
public function get_selectors( $form ) {
$selectors = array();
foreach ( $form['fields'] as $field ) {
if ( ! $this->is_applicable_field( $field ) ) {
continue;
}
$prefix = sprintf( '#input_%d_%d', $form['id'], $field->id );
if ( is_array( $field->inputs ) ) {
foreach ( $field->inputs as $input ) {
$bits = explode( '.', $input['id'] );
$input_id = $bits[1];
$selectors[] = "{$prefix}_{$input_id}";
}
} else {
$selectors[] = $prefix;
}
}
return $selectors;
}
public function is_applicable_form( $form ) {
$form_id = isset( $form['id'] ) ? $form['id'] : $form;
return $form_id == $this->_args['target_form_id'];
}
public function is_applicable_field( $field ) {
$field_map = $this->get_field_map();
return $this->is_applicable_form( $field->formId ) && in_array( $field->id, $field_map );
}
public function is_ajax_submission( $form_id, $is_ajax_enabled ) {
// Ensure GFFormDisplay is available before continuing to check (edge case with GPPA loading a pseudo form. See HS#25828)
return class_exists( 'GFFormDisplay' ) && isset( GFFormDisplay::$submission[ $form_id ] ) && $is_ajax_enabled;
}
}
# Configuration
new GW_Value_Exists_Validation( array(
'target_form_id' => 123,
'target_field_id' => 1,
'source_form_id' => 124,
'source_field_id' => 1,
'validation_message' => 'Hey! This isn\'t a valid reference number.',
) );
Hello, this creates a conflict with the signature of gravity forms. it is impossible to sign once this code is in place.
Hi,
I just tested the snippet with the signature field, but I wasn’t able to recreate the issue you’re experiencing. I’m guessing it could be specific to your setup. Please submit a ticket for this via our support form so we can dig into this further.
Best,