From 3acc03c804cb19b7b8f49a6242ad84725611feef Mon Sep 17 00:00:00 2001
From: vedanshujain <vedanshu.jain.2012@gmail.com>
Date: Mon, 11 May 2020 23:34:51 +0530
Subject: [PATCH] Add `verify_base_db` method to check if all base tables are
 present.

Optionally, also adds a notice in case all db tables are not present. Returns list of tables.

Note that we only check missing tables and don't care about exact table structure because many time tables are modified by merchants to better suit their needs (indexes, collations etc).
---
 .../views/html-notice-base-table-missing.php  | 32 +++++++++++++++++
 includes/class-wc-install.php                 | 35 ++++++++++++++++++-
 2 files changed, 66 insertions(+), 1 deletion(-)
 create mode 100644 includes/admin/views/html-notice-base-table-missing.php

diff --git a/includes/admin/views/html-notice-base-table-missing.php b/includes/admin/views/html-notice-base-table-missing.php
new file mode 100644
index 00000000000..b38cbd4d039
--- /dev/null
+++ b/includes/admin/views/html-notice-base-table-missing.php
@@ -0,0 +1,32 @@
+<?php
+/**
+ * Admin View: Notice - Base table missing.
+ *
+ * @package WooCommerce\Admin
+ */
+
+defined( 'ABSPATH' ) || exit;
+
+?>
+<div class="updated woocommerce-message">
+	<a class="woocommerce-message-close notice-dismiss"
+	   href="<?php echo esc_url( wp_nonce_url( add_query_arg( 'wc-hide-notice', 'base_tables_missing' ), 'woocommerce_hide_notices_nonce', '_wc_notice_nonce' ) ); ?>">
+			<?php esc_html_e( 'Dismiss', 'woocommerce' ); ?>
+	</a>
+
+	<p>
+		<strong><?php esc_html_e( 'Database tables missing', 'woocommerce' ); ?></strong>
+	</p>
+	<p>
+		<?php
+			echo wp_kses_post(
+				sprintf(
+				/* translators: %1%s: WooCommerce status page %2$s: Link to check again */
+					__( 'One or more tables required for WooCommerce to function are missing, some features may not work as expected. Please visit <a href="%1$s">WooCommerce status page</a> to see details, or <a href="%2$s"> check again.</a>', 'woocommerce' ),
+					admin_url( 'admin.php?page=wc-status#status-database' ),
+					wp_nonce_url( admin_url( 'admin.php?page=wc-status&tab=tools&action=verify_db_tables' ), 'debug_action' )
+				)
+			);
+			?>
+	</p>
+</div>
diff --git a/includes/class-wc-install.php b/includes/class-wc-install.php
index 4061f1a7c9d..96581e66cc8 100644
--- a/includes/class-wc-install.php
+++ b/includes/class-wc-install.php
@@ -287,6 +287,7 @@ class WC_Install {
 		WC()->wpdb_table_fix();
 		self::remove_admin_notices();
 		self::create_tables();
+		self::verify_base_tables();
 		self::create_options();
 		self::create_roles();
 		self::setup_environment();
@@ -303,6 +304,37 @@ class WC_Install {
 		do_action( 'woocommerce_installed' );
 	}
 
+	/**
+	 * Check if all the base tables are present.
+	 *
+	 * @param bool $modify_notice Whether to modify notice based on if all tables are present.
+	 *
+	 * @return array List of querues.
+	 */
+	public static function verify_base_tables( $modify_notice = true ) {
+		require_once ABSPATH . 'wp-admin/includes/upgrade.php';
+
+		$queries = dbDelta( self::get_schema(), false );
+		$missing_tables = array();
+		foreach ( $queries as $table_name => $result ) {
+			if ( "Created table $table_name" === $result ) {
+				$missing_tables[] = $table_name;
+			}
+		}
+
+		if ( 0 < count( $missing_tables ) ) {
+			if ( $modify_notice ) {
+				WC_Admin_Notices::add_notice( 'base_tables_missing' );
+			}
+		} else {
+			if ( $modify_notice ) {
+				WC_Admin_Notices::remove_notice( 'base_tables_missing' );
+			}
+			update_option( 'woocommerce-db-verified', WC()->version );
+		}
+		return $missing_tables;
+	}
+
 	/**
 	 * Reset any notices added to admin.
 	 *
@@ -630,8 +662,9 @@ class WC_Install {
 	 *      woocommerce_order_itemmeta - Order line item meta is stored in a table for storing extra data.
 	 *      woocommerce_tax_rates - Tax Rates are stored inside 2 tables making tax queries simple and efficient.
 	 *      woocommerce_tax_rate_locations - Each rate can be applied to more than one postcode/city hence the second table.
+	 *      wc_reserved_stock - Hold reserved stock during a checkout.
 	 */
-	private static function create_tables() {
+	public static function create_tables() {
 		global $wpdb;
 
 		$wpdb->hide_errors();