October 18, 2019: Fixed issue where field groups were not correctly limited on submission.
October 10, 2019: Fixed issue where Calculated Product fields were still added to order summary after their inventory was exhausted.
March 19, 2019: Fixed issue where remaining shortcode did not always target correct instance of Better Inventory.
November 17, 2018: Added support for fetching prepopulated values when limiting by field group.
April 26, 2018: Updated snippet for Gravity Forms 2.3; snippet now requires 2.3.
May 31, 2017: Updated "remaining" shortcode to correctly limit by field groups and approved payments flag.
January 27, 2017: Fixed bug with approved_payments_only parameter where entries with no payment were counting towards all inventory limits.
January 21, 2017: Added support for automatically limiting GP Limit Date-enabled Date fields and paired with an inventory input (via field_group parameter) so that days with exhausted inventory or not available.
January 17, 2017: Updated "remaining" shortcode to dynamically retrieve the limit for the specified form and field.
March 23, 2016: Added support for specifying "stock_qty" parameter as a function. Allows for dynamically setting the stock_qty during runtime.
March 15, 2016: Updated paid status to "Paid" from "Approved" to work with GF Payment Add-on framework.
October 5, 2014: Added support for "remaining" action on [gravityforms] shortcode.
October 1, 2014: Added support for "sum" action on [gravityforms] shortcode.
November 11, 2012: Fixed issue where database prefix was not applied via $wpdb->prefix.
Let’s dive into the code first.
| <?php | |
| /** | |
| * Gravity Wiz // Gravity Forms // Better Inventory with Gravity Forms | |
| * | |
| * Implements the concept of "inventory" with Gravity Forms by allowing the specification of a limit determined by the | |
| * sum of a specific field, typically a quantity field. | |
| * | |
| * @version 2.17 | |
| * @author David Smith <david@gravitywiz.com> | |
| * @license GPL-2.0+ | |
| * @link http://gravitywiz.com/better-inventory-with-gravity-forms/ | |
| */ | |
| class GW_Inventory { | |
| public $_args; | |
| public function __construct( $args ) { | |
| $this->_args = $this->parse_args( $args ); | |
| 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_pre_render_{$this->_args['form_id']}", array( $this, 'limit_by_field_values' ) ); | |
| add_filter( "gform_validation_{$this->_args['form_id']}", array( $this, 'limit_by_field_values_validation' ) ); | |
| // check 'field_group' for date fields; if found, limit based on exhausted inventory days. | |
| if( ! empty( $this->_args['field_group'] ) ) { | |
| add_filter( "gpld_limit_dates_options_{$this->_args['form_id']}", array( $this, 'limit_date_fields' ), 10, 2 ); | |
| } | |
| // add 'sum' action for [gravityforms] shortcode | |
| add_filter( 'gform_shortcode_sum', array( $this, 'shortcode_sum' ), 10, 2 ); | |
| add_filter( 'gform_shortcode_remaining', array( $this, 'shortcode_remaining' ), 10, 2 ); | |
| add_action( 'gwinv_before_get_sum', array( $this, 'before_get_sum' ) ); | |
| add_action( 'gwinv_after_get_sum', array( $this, 'after_get_sum' ) ); | |
| add_filter( 'gform_product_info', array( $this, 'handle_calculated_product_fields' ), 10, 3 ); | |
| if( $this->_args['enable_notifications'] ) { | |
| $this->enable_notifications(); | |
| } | |
| } | |
| public function parse_args( $args ) { | |
| $args = wp_parse_args( $args, array( | |
| 'form_id' => false, | |
| 'field_id' => false, | |
| 'input_id' => false, | |
| 'stock_qty' => false, | |
| 'out_of_stock_message' => __( 'Sorry, this item is out of stock.' ), | |
| 'not_enough_stock_message' => __( 'You ordered %1$s of this item but there are only %2$s of this item left.' ), | |
| 'approved_payments_only' => false, | |
| 'hide_form' => false, | |
| 'enable_notifications' => false, | |
| 'field_group' => array() | |
| ) ); | |
| /** | |
| * @var $stock_qty | |
| * @var $field_group | |
| */ | |
| extract( $args ); | |
| if( ! $stock_qty && isset( $limit ) ) { | |
| $args['stock_qty'] = $limit; | |
| unset( $args['limit'] ); | |
| } | |
| if( isset( $limit_message ) ) { | |
| $args['out_of_stock_message'] = $limit_message; | |
| unset( $args['limit_message'] ); | |
| } | |
| if( isset( $validation_message ) ) { | |
| $args['not_enough_stock_message'] = $validation_message; | |
| unset( $args['validation_message'] ); | |
| } | |
| if( ! $args['input_id'] ) { | |
| $args['input_id'] = $args['field_id']; | |
| unset( $args['field_id'] ); | |
| } | |
| if( $field_group && ! is_array( $field_group ) ) { | |
| $args['field_group'] = array( $field_group ); | |
| } | |
| return $args; | |
| } | |
| public function enable_notifications() { | |
| if( ! class_exists( 'GW_Notification_Event' ) ) { | |
| _doing_it_wrong( 'GW_Inventory::$enable_notifications', __( 'Inventory notifications require the \'GW_Notification_Event\' class.' ), '1.0' ); | |
| } else { | |
| $event_slug = "gwinv_out_of_stock_{$this->_args['input_id']}"; | |
| $event_name = GFForms::get_page() == 'notification_edit' ? $this->get_notification_event_name() : __( 'Event name is only populated on Notification Edit view; saves a DB call to get the form on every ' ); | |
| $this->_notification_event = new GW_Notification_Event( array( | |
| 'form_id' => $this->_args['form_id'], | |
| 'event_name' => $event_name, | |
| 'event_slug' => $event_slug, | |
| 'trigger' => array( $this, 'notification_event_listener' ) | |
| ) ); | |
| } | |
| } | |
| public function limit_by_field_values( $form ) { | |
| if( $this->is_in_stock() ) { | |
| return $form; | |
| } | |
| if( $this->_args['hide_form'] ) { | |
| add_filter( "gform_get_form_filter_{$form['id']}", array( $this, 'get_out_of_stock_message' ) ); | |
| } else if( empty( $this->_args['field_group'] ) ) { | |
| add_filter( 'gform_field_input', array( $this, 'hide_field' ), 10, 2 ); | |
| } | |
| return $form; | |
| } | |
| public function limit_by_field_values_validation( $validation_result ) { | |
| $input_id = $this->_args['input_id']; | |
| $limit = $this->get_stock_quantity(); | |
| $validation_message = $this->_args['not_enough_stock_message']; | |
| $form = $validation_result['form']; | |
| $exceeded_limit = false; | |
| foreach( $form['fields'] as &$field ) { | |
| if( $field['id'] != intval( $input_id ) ) { | |
| continue; | |
| } | |
| $requested_qty = rgpost( 'input_' . str_replace( '.', '_', $input_id ) ); | |
| $field_sum = $this->get_sum(); | |
| if( rgblank( $requested_qty ) || $field_sum + $requested_qty <= $limit ) { | |
| continue; | |
| } | |
| $exceeded_limit = true; | |
| $stock_left = $limit - $field_sum >= 0 ? $limit - $field_sum : 0; | |
| $field['failed_validation'] = true; | |
| $field['validation_message'] = sprintf( $validation_message, $requested_qty, $stock_left ); | |
| } | |
| if( $exceeded_limit && ! empty( $this->_args['field_group'] ) ) { | |
| foreach( $form['fields'] as &$field ) { | |
| if( in_array( $field->id, $this->_args['field_group'] ) ) { | |
| $field['failed_validation'] = true; | |
| $field['validation_message'] = sprintf( $validation_message, $requested_qty, $stock_left ); | |
| } | |
| } | |
| } | |
| $validation_result['form'] = $form; | |
| $validation_result['is_valid'] = ! $validation_result['is_valid'] ? false : ! $exceeded_limit; | |
| return $validation_result; | |
| } | |
| public function limit_by_field_group( $query, $form_id, $input_id ) { | |
| global $wpdb; | |
| if( $input_id != $this->_args['input_id'] ) { | |
| return $query; | |
| } | |
| $form = GFAPI::get_form( $form_id ); | |
| $join = $where = array(); | |
| foreach( $this->_args['field_group'] as $index => $field_id ) { | |
| $field = GFFormsModel::get_field( $form, $field_id ); | |
| $alias = sprintf( 'fgld%d', $index + 1 ); | |
| // Fetch entry from submission if available. Otherwise, get default/dynpop value. | |
| if( rgpost( 'gform_submit' ) == $form_id ) { | |
| $value = $field->get_value_save_entry( GFFormsModel::get_field_value( $field ), $form, null, null, null ); | |
| } else { | |
| $value = $field->get_value_default_if_empty( GFFormsModel::get_parameter_value( $field->inputName, array(), $field ) ); | |
| } | |
| $join[] = "\nINNER JOIN {$wpdb->prefix}gf_entry_meta {$alias} ON em.entry_id = {$alias}.entry_id"; | |
| $where[] = $wpdb->prepare( "CAST( {$alias}.meta_key as unsigned ) = %d AND {$alias}.meta_value = %s ", $field_id, $value ); | |
| } | |
| $query['join'] .= implode( "\n", $join ); | |
| $query['where'] .= sprintf( "\n AND %s", implode( "\nAND ", $where ) ); | |
| return $query; | |
| } | |
| public function limit_date_fields( $options, $form ) { | |
| global $wpdb; | |
| foreach( $form['fields'] as $field ) { | |
| if( ! in_array( $field->id, $this->_args['field_group'] ) || $field->get_input_type() != 'date' || $field->dateType != 'datepicker' ) { | |
| continue; | |
| } | |
| $query = self::get_sum_query( $field->formId, $this->_args['input_id'] ); | |
| if( $this->_args['approved_payments_only'] ) { | |
| $query = $this->limit_by_approved_payments_only( $query ); | |
| } | |
| if( ! empty( $this->_args['field_group'] ) ) { | |
| // add our Date field to the front of the array so we can reliably target it when replacing the queries below | |
| array_unshift( $this->_args['field_group'], $field->id ); | |
| $this->_args['field_group'] = array_unique( $this->_args['field_group'] ); | |
| $query = $this->limit_by_field_group( $query, $field->formId, $this->_args['input_id'] ); | |
| } | |
| $regex = sprintf( '/(CAST\( fgld1.meta_key as unsigned \) = %d) AND fgld1.meta_value = \'(?:[\w\d]*)\'/', $field->id ); | |
| preg_match( $regex , $query['where'], $match ); | |
| if( ! empty( $match ) ) { | |
| list( $search, $replace ) = $match; | |
| $query['where'] = str_replace( $search, $replace, $query['where'] ); | |
| } | |
| $query['select'] = 'SELECT sum( em.meta_value ) as total, fgld1.meta_value as date'; | |
| $query['group_by'] = 'GROUP BY date'; | |
| $query['having'] = sprintf( 'HAVING total >= %d', $this->get_stock_quantity() ); | |
| $sql = implode( "\n", $query ); | |
| $results = $wpdb->get_results( $sql ); | |
| foreach( $results as $result ) { | |
| $options[ $field->id ]['exceptionsMode'] = 'disable'; | |
| $options[ $field->id ]['exceptions'][] = date( 'm/d/Y', strtotime( $result->date ) ); | |
| } | |
| } | |
| return $options; | |
| } | |
| public function get_stock_quantity() { | |
| $stock = $this->_args['stock_qty']; | |
| if( is_callable( $stock ) ) { | |
| $stock = call_user_func( $stock ); | |
| } | |
| return $stock; | |
| } | |
| public function is_in_stock() { | |
| $count = $this->get_sum();//self::get_field_values_sum( $this->_args['form_id'], $this->_args['input_id'] ); | |
| return $count < $this->get_stock_quantity(); | |
| } | |
| public function hide_field( $field_content, $field ) { | |
| if( $field['id'] == intval( $this->_args['input_id'] ) ) { | |
| return "<div class=\"ginput_container\">{$this->_args['out_of_stock_message']}</div>"; | |
| } | |
| return $field_content; | |
| } | |
| public function notification_event_listener() { | |
| // really is no better hook to use to send custom notifications just yet | |
| add_filter( "gform_confirmation_{$this->_args['form_id']}", array( $this, 'send_out_of_stock_notifications' ), 10, 3 ); | |
| } | |
| public function send_out_of_stock_notifications( $return, $form, $entry ) { | |
| // if product is still in stock or the entry is spam, don't sent notification | |
| if( $this->is_in_stock() || $entry['status'] == 'spam' ) | |
| return $return; | |
| // if product is out of stock and no qty of the product is in current order, assume that out of stock notifications have already been sent | |
| $requested_qty = intval( rgar( $entry, (string) $this->_args['input_id'] ) ); | |
| if( $requested_qty <= 0 ) | |
| return $return; | |
| $this->_notification_event->send_notifications( $this->_notification_event->get_event_slug(), $form, $entry ); | |
| return $return; | |
| } | |
| public function get_notification_event_name() { | |
| $form = GFAPI::get_form( $this->_args['form_id'] ); | |
| $field = GFFormsModel::get_field( $form, $this->_args['input_id'] ); | |
| $event_name = sprintf( __( '%s: Out of Stock' ), GFCommon::get_label( $field ) ); | |
| return $event_name; | |
| } | |
| public function shortcode_sum( $output, $atts ) { | |
| $atts = shortcode_atts( array( | |
| 'id' => false, | |
| 'input_id' => false | |
| ), $atts ); | |
| extract( $atts ); // gives us $id, $input_id | |
| return intval( self::get_field_values_sum( $id, $input_id ) ); | |
| } | |
| public function shortcode_remaining( $output, $atts ) { | |
| /** | |
| * @var $id | |
| * @var $input_id | |
| * @var $limit | |
| */ | |
| $atts = shortcode_atts( array( | |
| 'id' => false, | |
| 'input_id' => false, | |
| 'limit' => false, | |
| ), $atts ); | |
| extract( $atts ); // gives us $id, $input_id | |
| if( $input_id == $this->_args['input_id'] && $id == $this->_args['form_id'] ) { | |
| $limit = $limit ? $limit : $this->get_stock_quantity(); | |
| $remaining = $limit - intval( $this->get_sum() ); | |
| $output = max( 0, $remaining ); | |
| } | |
| return $output; | |
| } | |
| public function get_sum() { | |
| if( $this->_args['approved_payments_only'] ) { | |
| add_filter( 'gwinv_query', array( $this, 'limit_by_approved_payments_only' ) ); | |
| } | |
| if( ! empty( $this->_args['field_group'] ) ) { | |
| add_filter( 'gwinv_query', array( $this, 'limit_by_field_group' ), 10, 3 ); | |
| } | |
| $sum = self::get_field_values_sum( $this->_args['form_id'], $this->_args['input_id'] ); | |
| remove_filter( 'gwinv_query', array( $this, 'limit_by_approved_payments_only' ) ); | |
| remove_filter( 'gwinv_query', array( $this, 'limit_by_field_group' ) ); | |
| return $sum; | |
| } | |
| public function limit_by_approved_payments_only( $query ) { | |
| $valid_statuses = array( 'Approved' /* old */, 'Paid', 'Active' ); | |
| $query['where'] .= sprintf( ' AND ( e.payment_status IN ( %s ) OR e.payment_status IS NULL )', self::prepare_strings_for_mysql_in_statement( $valid_statuses ) ); | |
| return $query; | |
| } | |
| public function get_out_of_stock_message() { | |
| return $this->_args['out_of_stock_message']; | |
| } | |
| /** | |
| * Calculated Product fields limited by their default quantity should be excluded from the order summary. | |
| * | |
| * Since their value is calculated post submission, they function uniquely from other product fields. | |
| * | |
| * @param $order | |
| * @param $form | |
| * @param $entry | |
| * | |
| * @return mixed | |
| */ | |
| public function handle_calculated_product_fields( $order, $form, $entry ) { | |
| foreach( $order['products'] as $field_id => $product ) { | |
| // Check for if target input ID is for the current field and is targeting a Product field default quantity input (i.e. 1.3). | |
| if( $field_id != intval( $this->_args['input_id'] ) || rgar( explode( '.', $this->_args['input_id'] ), 1 ) != '3' ) { | |
| continue; | |
| } | |
| $field = GFAPI::get_field( $form, $field_id ); | |
| if( $field->get_input_type() !== 'calculation' ) { | |
| continue; | |
| } | |
| if( ! $this->is_in_stock() ) { | |
| unset( $order['products'][ $field_id ] ); | |
| } | |
| } | |
| return $order; | |
| } | |
| public static function get_field_values_sum( $form_id, $input_id ) { | |
| global $wpdb; | |
| $query = self::get_sum_query( $form_id, $input_id ); | |
| $sql = implode( "\n", $query ); | |
| $result = $wpdb->get_var( $sql ); | |
| return intval( $result ); | |
| } | |
| public static function get_sum_query( $form_id, $input_id, $suppress_filters = false ) { | |
| global $wpdb; | |
| $query = array( | |
| 'select' => 'SELECT sum( em.meta_value )', | |
| 'from' => "FROM {$wpdb->prefix}gf_entry_meta em", | |
| 'join' => "INNER JOIN {$wpdb->prefix}gf_entry e ON e.id = em.entry_id", | |
| 'where' => $wpdb->prepare( " | |
| WHERE em.form_id = %d | |
| AND em.meta_key = %s | |
| AND e.status = 'active'\n", | |
| $form_id, $input_id | |
| ) | |
| ); | |
| if( class_exists( 'GF_Partial_Entries' ) ) { | |
| $query['where'] .= "and em.entry_id NOT IN( SELECT entry_id FROM {$wpdb->prefix}gf_entry_meta WHERE meta_key = 'partial_entry_id' )"; | |
| } | |
| if( ! $suppress_filters ) { | |
| $query = apply_filters( 'gwlimitbysum_query', $query, $form_id, $input_id ); | |
| $query = apply_filters( 'gwinv_query', $query, $form_id, $input_id ); | |
| $query = apply_filters( "gwinv_query_{$form_id}", $query, $form_id, $input_id ); | |
| $query = apply_filters( "gwinv_query_{$form_id}_{$input_id}", $query, $form_id, $input_id ); | |
| } | |
| return $query; | |
| } | |
| public static function prepare_strings_for_mysql_in_statement( $strings ) { | |
| $wrapped = array(); | |
| foreach( $strings as $string ) { | |
| $wrapped[] = sprintf( '"%s"', $string ); | |
| } | |
| return implode( ', ', $wrapped ); | |
| } | |
| } | |
| class GWLimitBySum extends GW_Inventory { } |
How do I install this snippet?
Easy peasy. Just copy and paste the code above into your theme's functions.php file.
Do I need to modify this snippet to work with my form?
You don’t have to modify the snippet itself. Just the parameters with which you initialize it.
| <?php | |
| new GW_Inventory( array( | |
| 'form_id' => 363, | |
| 'field_id' => 2.3, | |
| 'stock_qty' => 20, | |
| 'out_of_stock_message' => 'Sorry, there are no more tickets!', | |
| 'not_enough_stock_message' => 'You ordered %1$s tickets. There are only %2$s tickets left.', | |
| 'approved_payments_only' => false, | |
| 'hide_form' => false, | |
| 'enable_notifications' => true | |
| ) ); |
Parameters
$form_idthe ID of the form you are working with.$field_idthe ID of your product or quantity field. If using a Single Product field, you’ll need to specify the quantity input ID which will always be{field ID}.3(ie if the field ID is12, the quantity input ID will be12.3). If using a separate Quantity field, simply specify the field ID.$stock_qtythe number of this item you have available.$out_of_stock_messagethe message which should be displayed to users when the product limit has been reached. You can get fancy with this and add HTML as well. Be sure to escape any double quotes with a backslash. Here’s a more advanced example:$sum_limit_message = '<div style="border: 1px solid #e6db55; background-color: #FFFFE0; padding: 10px;">Sorry, this show is sold out.</div>'; 
Better Inventory: Limit Message$not_enough_stock_messagethe message which should be displayed on the field if the limit has not been reached, but the user’s requested quantity would exceed the product limit.
Better Inventory: Limit Validation Message$approved_payments_onlytrue/falseindicate whether all submissions for this field should be counted against the limit or only submissions with an approved payment. You’ll want to be careful here when using PayPal Standard due to the delay between the form submission and the payment being approved. It could lead to users exceeding the limit.$hide_formby default this snippet will only hide the field when the limit has been reached. If you would rather hide the entire form, set this totrue.$enable_notificationsenable the ability to create notifications that are sent when the stock of a product (or any configured field) has been exhausted
Shortcodes
Remaining
Show the quantity remaining for the specified input and limit.[gravityforms action="remaining" id="1" input_id="2.3" limit="50"]Sum
Show the current sum of quantities ordered for this field across all entries.[gravityforms action="sum" id="1" input_id="2.3"]
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Any chance this can work on a select/dropdown field? Was hoping to have an option where the user could select from one event date or the other (and each event date is limited to 4 registrations). If I’m reading this correctly, it only seems to work on a single field (that doesn’t have variations). I have a bit of a complicated situation where I’m using a WooCommerce product that can only be purchased 8 times (a workshop) and then there is an option add-on where users can buy it 4x per date – so it’s almost like I have dual stock management going on where I need to manage stock for the master product and then also at the variation level but I don’t believe there is a way for WooCommerce to do that either. That’s why I was hoping within the Gravity Forms Product add-on I could manage the stock there somehow.
Hi Justin, Gravity Forms Limit Choices is a great way to provide inventory per choice in a Drop Down field. This can be combined with our very powerful Field Groups snippet to make the inventory specific to the choice and any other variations selected in other fields (included a Date field or a Drop Down field with available dates).
Hi David,
Thank you for this code. I am using gravity forms product add-ons in Woocommerce and someone can place an order for more stock than is available, so your code snippet works great.
However what I need to do is vary the stock quantity (used in the GW_Inventory parameters) based around the current product stock quantity. No matter what I try to do I cannot get the code to recognise either the product id or the post id.
If I hard code the product id then something like this works fine.
http://snippi.com/s/dchklx9
I can happily output the post / product id to the page but when I try the same in your GW_Inventory parameters it returns a null value, and the main code fails.
Anything you could do to point me in the right direction would be much appreciated.
Thanks
Hi Jonathan, here’s an example of the preferred method for current-post-specific stock quantities: http://snippi.com/s/84wz11f
I have this integrated with a payment gateway Stripe. In the new release of Gravity Forms Stripe, we have the option to have the secure checkout be redirected to a “stripe checkout” form ( hosted by Stripe ) I have found that the inventory is subtracted even if the payment isn’t complete..
Is there a way to only take inventory if payment is successful ?
Thanks.
Hi Josh, you’re looking for the “approved_payments_only” parameter.
There it is. I apologize this was right in front of me :-)