torvista / zen_cart-back_in_stock_notifications

Customers can subscribe to a notification when a product in not in stock.

Zen Cart - Back in Stock Notifications

If a product is out of stock, customers can subscribe/request to receive a notification when that product becomes available again.

This was based on the original CEON version, not the forked ajax version. Neither are supported anymore, but the functionality is well worthwhile, and I use it, so am encouraging use and development here despite it being the usual yelling into the void...

I've been modifying it for years, multi-language and attributes handling being the most significant omissions from the original code.

As a result, this code is hugely different from the plugin version, so always test on a development server: DO NOT drop it into your production server without testing first. It's compatible with the current Zen Cart 1.5.8 and php7.3+.

Note that the original documentation in the docs folder has NOT been updated, so the file list is out of date.

Installation/Upgrade

1. On your development server, remove original BISN files.
2. Copying all this fileset will not overwrite any other files: they are all new.
   But, regarding the template files, you will find bootstrap CLONE and responsive_classic CLONE folders containing modified template files (suffixed BISN php) for you to compare and merge into your own equivalents.

Go to the Admin Catalog->BISN Notifications Admin page to auto upgrade/install.

Use/How it Works

The use of the BISN service may be restricted to only logged-in users to prevent spam from the BISN form, or you can try the ReCaptcha plugin
https://github.com/torvista/Zen_Cart-Google_reCAPTCHA

The BISN observer determines if the product is out of stock and hence shows the BISN link and form.
The user fills in the form on the product info page or if logged-in, the data is filled automatically.
If the submitted form data has an error, the BISN subscribe page is shown, similar to Ask a Question. If the form data is valid, the BISN subscribe page is skipped, the subscripion is recorded and a success message is shown.

Languages

If you have a single language store, you should not see anything about languages.

For a multiple-language store, although real notification emails will be sent in the same language as that used by the customer for the subscription, it requires manual intervention.

This is done by selecting Option 4: this sends the emails in the language that matches the currently-selected admin-language. Then, changing the admin language will reload the Option 4 page and send the other emails that correspond to this other admin language etc.
Todo: make this automatic.

Testing

If you want to test the real sending of notifications repeatedly/not deleting the subscriptions:
in admin\back_in_stock_notifications.php
set this to false
$delete_customer_subscriptions = true;

The BISN configuration allows an alternative email destination for the test emails to prevent cluttering up the business email account while testing.

Optional copies of real Notification Subscription Emails are sent to what is defined in the BISN Admin (SEND_EXTRA_BACK_IN_STOCK_NOTIFICATION_SUBSCRIPTION_EMAILS_TO).

Ceon XHTML template

This plugin uses a unique (to CEON/Conor) method of building the forms and emails using templates and variable substitutions.
It's complicated to understand/modify, and something that needs replacing by ZC core methods... feel free to have a go and contribute that.

Problems/Ideas

Any problems or suggestions: open an issue in GitHub, not in the forum.

Changelog

16/08/2024: update and simplify template files

20/01/2023: added support for Google Recaptcha: https://github.com/torvista/Zen_Cart-Google_reCAPTCHA

18/11/2023 or thereabouts Add multi-language to email sending. A reply to the Admin copy of BISN subscription email now replies to customer Replace tabs with spaces with all files. Admin Option 1 list subscriptions by product Option 2 list all subscriptions Bugfix: handle fatal error for a missing/deleted product Added column sorts/set column sort links to table id anchor Hide model column if not used. Add Delete buttons for each product/subscription. Corrected paging display text. Added support for Google reCaptcha. And lots more fun for all the family.

11/11/2023: moved admin functions file so only loaded with BISN admin page Remove duplicated function zen_get_products_model from bis_functions.php Renamed BACK_IN_STOCK_NOTIFICATION_ENABLED to BACK_IN_STOCK_NOTIFICATIONS_ENABLED Minor changes to installer messages and processing. Add delete of single subscriptions of a product

06/11/2023: relocated required/optional template files to main file structure. Updated template files based on ZC158 responsive_classic.

23/07/23: Use ZC158 admin header, move css to separate file.

16/02/22: Bugfix for duplicated subscription links when no login required.

Removed: /modules/ceon_form_bis as functionality duplicated in observer class

Removed: unnecessary observer auto loaders/observers made auto-loading

Bugfix for missing product_model in account BISN listing

Bugfix for missing image in account BISN listing, Update button

Modified: language defines

Removed: modified core file functions_general

Removed: empty language folders

Fixes for warnings in strict mode/php8 compatibility

Miscellaneous IDE recommendations, strict comparisons, short-array syntax

zen_cart-back_in_stock_notifications's Issues

account: --> PHP Warning: Undefined array key "product_model" in tpl_account_back_in_stock_notifications_default.php

The model is referenced but it is never retrieved in the header, nor is it contemplated in the table.
Commenting out for now.

remove/replace class.CeonEmailValidation

only used by includes\modules\pages\back_in_stock_notification_subscribe\header_php.php

remove class.CeonXHTMLHiTemplate: simplify email templating to ZC style

When this is stable:
zencart/zencart#5499

Simplify table sorting

Text email templates have undefined placeholders

So are shown in received email as unreplaced.
$URL_INTRO

$URL_VALUE

PHP Warning: Undefined variable $pagination_columns in admin\back_in_stock_notifications.php on line 557.

Zen_Cart-Back_in_Stock_Notifications/files/admin/back_in_stock_notifications.php

Line 555 in 1fa19c9

$pagination_columns .= '<table border="0" width="100%" cellspacing="0" cellpadding="0">' .

Two instances used of concatentation, but $pagination_columns has not been initialised.

PHP Warning: Undefined array key "product_model" in template_default\templates\tpl_account_back_in_stock_notifications_default.php on line 150.

When logged in, and viewing BISN list.

PHP Warning: Undefined array key "page" in admin\back_in_stock_notifications.php on line 129.

Zen_Cart-Back_in_Stock_Notifications/files/admin/back_in_stock_notifications.php

Line 129 in c7f6e37

if ($_GET['page'] != -1) {

allow admin deletion of BISN notifications by product/customer

done on my site

Spammers sending malicious links in NAME field

It seems that spammers are using the module to send SPAM LINKS which contain malicious links in the NAME field.

The module only asks for three fields: Name, Email Address, and Confirm Email Address. What is happening is that they put a legitimate email address in the two fields (the person they want to spam), but they put their malicious link in the NAME field. Since the form is submitted and authenticated by our own SMTP domain, it isn't seen as SPAM (since our domain is originating the email) and it gets sent to the customer.

Here is a screenshot of what the SPAM looks like: https://i.postimg.cc/c15tMdZj/screenshot-132.png

Notice that in this example, the NAME FIELD that the spammer used was: "🍒 Amber want to play with you! Start Game: https://letsg0dancing.page.link/go?exx 🍒"

So when the recipient (whose address is entered in the email field) opens the Back In Stock email, the very first line (which is the NAME field) contains the malicious link.

SOME THOUGHTS ON ADDRESSING THE ISSUE:

1. Some sort of CAPTCHA might be applied to help reduce automated spammers from abusing the form. However, this won't stop spammers from manually entering in the information.

2. At the very least, perhaps run a string-check on the NAME and reject anything that is 1) over a certain amount of characters, and 2) reject anything that has an "HTTP" or ".com" in it, and 3) reject any name with "more than two blank spaces" in it.

That alone should weed out most fake names, since most names won't be over about 10 characters, and most won't have a www/http string, and most won't have more than two blank spaces (John Smith Jr, etc).

3. As a complete fail-safe, perhaps having an option to DISABLE the NAME field would work. In other words, only allow an email address to be entered. This would still "spam" though, but it won't contain any malicious links because there would be no name field.

PHP Warning: Undefined variable $image in tpl_account_back_in_stock_notifications_default.php

Zen_Cart-Back_in_Stock_Notifications/files/includes/templates/template_default/templates/tpl_account_back_in_stock_notifications_default.php

Lines 56 to 58 in ec63317

	$image_src = zen_output_string($template->get_template_dir(BUTTON_IMAGE_BACK, DIR_WS_TEMPLATE,
	$current_page_base, 'buttons/' . $_SESSION['language'] . '/') . $image);

replace BISN function get_customer with ZC function

and so can remove bis_functions.php

Subscription link repeated on product page when login not required

Add a BISN subscription/notification for a specific out of stock attribute

Evidently this is only applicable for sites that have filled the hole that is control-of-attributes-stock with Stock By Attributes (SBA) or Products Options Stock Manager (POSM).

I've done a hack for POSM but it's not for public consumption, so it's a work in progress/up for consultation.

PHP Fatal error: 1055:'DBNAME.pd.products_name' isn't in GROUP BY :

php 8.1.9
When entering admin BISN page.

--> PHP Fatal error: 1055:'DBNAME.pd.products_name' isn't in GROUP BY ::
SELECT bisns.product_id, pd.products_name, p.products_model, COUNT(*) AS num_subscribers, p.products_type, p.products_quantity AS current_stock, cd.categories_name, cd.categories_id , bisns.product_name_extra FROM back_in_stock_notification_subscriptions bisns LEFT JOIN products_description pd ON (pd.products_id = bisns.product_id AND pd.language_id = '1') LEFT JOIN products p ON p.products_id = pd.products_id LEFT JOIN categories_description cd ON (p.master_categories_id = cd.categories_id AND cd.language_id = '1') WHERE 1 = 1 GROUP BY bisns.product_id ORDER BY p.products_model
==> ADMIN\back_in_stock_notifications.php on line 165.

make multi-language

done on my site

improve BISN email content to encourage purchase (image, description, advantages....etc.)

related article
https://www.drip.com/blog/back-in-stock-email-examples

Date format in \includes\modules\pages\back_in_stock_notification_subscribe\header_php.php

In \includes\modules\pages\back_in_stock_notification_subscribeLine\header_php.php
line 193 has the date format as
'date_subscribed' => date('Y-m-d H:m:i')
I believe that it should be 'date_subscribed' => date('Y-m-d H:m:i')

Enable bulk selection-delete of individual subscribers

handle missing product

crashes BISN admin pages if a product with subscriptions has been deleted

PHP Fatal error: Uncaught Error: Undefined constant "BACK_IN_STOCK_REQUIRES_LOGIN"

[15-Feb-2022 20:23:03 America/Vancouver] PHP Fatal error: Uncaught Error: Undefined constant "BACK_IN_STOCK_REQUIRES_LOGIN" in /usr/home/sites/zen15/www/includes/languages/english/extra_definitions/back_in_stock_notifications.php:23
Stack trace:
#0 /usr/home/sites/zen15/www/includes/modules/extra_definitions.php(45): include()
#1 /usr/home/sites/zen15/www/includes/init_includes/init_templates.php(85): include('/usr/home/sites...')
#2 /usr/home/sites/zen15/www/includes/autoload_func.php(37): require_once('/usr/home/sites...')
#3 /usr/home/sites/zen15/www/includes/application_top.php(222): require('/usr/home/sites...')
#4 /usr/home/sites/zen15/www/index.php(25): require('/usr/home/sites...')
#5 {main}
thrown in /usr/home/sites/zen15/www/includes/languages/english/extra_definitions/back_in_stock_notifications.php on

--- /usr/home/sites/zen15/www/includes/languages/english/extra_definitions/back_in_stock_notifications.php.old  2022-02-15 20:27:17.771032000 -0800
+++ /usr/home/sites/zen15/www/includes/languages/english/extra_definitions/back_in_stock_notifications.php      2022-02-15 20:30:26.138009000 -0800
@@ -20,7 +20,7 @@
  * Note that the link is added in place of %s, %s must be present for the link to work!
  */
 define('BACK_IN_STOCK_NOTIFICATION_TEXT_PRODUCT_LISTING_ALREADY_SUBSCRIBED', '<br />You have requested to be notified when this product is back in stock.');
-if (BACK_IN_STOCK_REQUIRES_LOGIN == '1') {
+if (defined('BACK_IN_STOCK_REQUIRES_LOGIN') && BACK_IN_STOCK_REQUIRES_LOGIN == '1') {
   define('BACK_IN_STOCK_NOTIFICATION_TEXT_PRODUCT_LISTING_FORM_LINK', '<br />To be notified when this product is back in stock please <a href="%s">click here</a>. (Requires account)');
 } else {
   define('BACK_IN_STOCK_NOTIFICATION_TEXT_PRODUCT_LISTING_FORM_LINK', '<br />To be notified when this product is back in stock please <a href="%s">click here</a>.');
@@ -30,7 +30,7 @@
  * Text/HTML for other pages.
  */
 define('BACK_IN_STOCK_NOTIFICATION_TEXT_ALREADY_SUBSCRIBED', 'You have requested to be notified when this product is back in stock.');
-if (BACK_IN_STOCK_REQUIRES_LOGIN == '1') {
+if (defined('BACK_IN_STOCK_REQUIRES_LOGIN') && BACK_IN_STOCK_REQUIRES_LOGIN == '1') {
   define('BACK_IN_STOCK_NOTIFICATION_TEXT_FORM_LINK', 'To be notified when this product is back in stock please <a href="%s">click here</a>. (Requires account)');
 } else {
   define('BACK_IN_STOCK_NOTIFICATION_TEXT_FORM_LINK', 'To be notified when this product is back in stock please <a href="%s">click here</a>.');

PHP Fatal error: Undefined constant "ACCOUNT_BACK_IN_STOCK_NOTIFICATIONS_TABLE_TITLE" in tpl_account_back_in_stock_notifications_default.php:110

Zen_Cart-Back_in_Stock_Notifications/files/includes/templates/template_default/templates/tpl_account_back_in_stock_notifications_default.php

Lines 108 to 110 in 4fde019

	// Add the table headers and update button
	$product_back_in_stock_notifications_table_title =
	ACCOUNT_BACK_IN_STOCK_NOTIFICATIONS_TABLE_TITLE;

This has been missing forever!

review embedded code in function_general

PHP Warning: Undefined variable $image in tpl_account_back_in_stock_notifications_default.php on line 188.

use customer reply-to address in admin BISN email

to allow quick reply if necessary

PHP Warning: Undefined variable $subscriptions_split admin\back_in_stock_notifications.php on line 530.

Zen_Cart-Back_in_Stock_Notifications/files/admin/back_in_stock_notifications.php

Lines 525 to 533 in 5c072ec

	if (isset($products_split)) {
	$split_object = $products_split;
	$count_text = TEXT_DISPLAY_NUMBER_OF_PRODUCTS;
	} else {
	$split_object = $subscriptions_split;
	$count_text = TEXT_DISPLAY_NUMBER_OF_BACK_IN_STOCK_NOTIFICATIONS;
	}

allow selection of BISN notifications by product

to not send all at once

PHP Fatal error: bisns.name' isn't in GROUP BY: Admin, Preview Emails

PHP Fatal error: 1055:'DBNAME.bisns.name' isn't in GROUP BY ::
SELECT
bisns.email_address, bisns.name, bisns.languages_id, c.customers_email_address, c.customers_firstname,
c.customers_lastname
FROM
back_in_stock_notification_subscriptions bisns
LEFT JOIN
products p
ON
p.products_id = bisns.product_id
LEFT JOIN
customers c
ON
c.customers_id = bisns.customer_id
WHERE
p.products_quantity > 0
AND
bisns.languages_id = 1
GROUP BY
email_address, customers_email_address
ORDER BY
email_address, customers_email_address ==> (as called by) ADMIN\includes\functions\back_in_stock_notifications_functions.php on line 82 <== in includes/classes/db/mysql/query_factory.php on line 665.

PHP Warning: Undefined array key "page" in admin\back_in_stock_notifications.php on line 536.

Zen_Cart-Back_in_Stock_Notifications/files/admin/back_in_stock_notifications.php

Line 536 in dbd3be8

if ($_GET['page'] != -1) {