From f5078cc04221e916b7d41ca8c598a06bdd8a42ed Mon Sep 17 00:00:00 2001
From: Seamus Lee <seamuslee001@gmail.com>
Date: Sat, 6 May 2017 13:02:35 +1000
Subject: [PATCH] NFC Add in function to check if Foreign key is there to make
 upgrade more stable

---
 CRM/Core/BAO/SchemaHandler.php            | 31 +++++++++++++++------
 CRM/Upgrade/Incremental/php/FourSeven.php | 33 ++++++++---------------
 2 files changed, 34 insertions(+), 30 deletions(-)

diff --git a/CRM/Core/BAO/SchemaHandler.php b/CRM/Core/BAO/SchemaHandler.php
index fbf194411a..51b5b77a87 100644
--- a/CRM/Core/BAO/SchemaHandler.php
+++ b/CRM/Core/BAO/SchemaHandler.php
@@ -640,15 +640,13 @@ MODIFY      {$columnName} varchar( $length )
   }
 
   /**
-   * Remove a foreign key from a table if it exists.
-   *
-   * @param $table_name
-   * @param $constraint_name
-   *
-   * @return bool
+   * Check if a foreign key Exists
+   * @param string $table_name
+   * @param string $constraint_name
+   * @return bool TRUE if FK is found
    */
-  public static function safeRemoveFK($table_name, $constraint_name) {
-
+  public static function checkFKExists($table_name, $constraint_name) {
+    $found = FALSE;
     $config = CRM_Core_Config::singleton();
     $dbUf = DB::parseDSN($config->dsn);
     $query = "
@@ -666,6 +664,23 @@ MODIFY      {$columnName} varchar( $length )
     $dao = CRM_Core_DAO::executeQuery($query, $params);
 
     if ($dao->fetch()) {
+      $found = TRUE;
+    }
+    return $found;
+  }
+
+  /**
+   * Remove a foreign key from a table if it exists.
+   *
+   * @param $table_name
+   * @param $constraint_name
+   *
+   * @return bool
+   */
+  public static function safeRemoveFK($table_name, $constraint_name) {
+    $check = self::checkFKExists($table_name, $constraint_name);
+
+    if ($check) {
       CRM_Core_DAO::executeQuery("ALTER TABLE {$table_name} DROP FOREIGN KEY {$constraint_name}", array());
       return TRUE;
     }
diff --git a/CRM/Upgrade/Incremental/php/FourSeven.php b/CRM/Upgrade/Incremental/php/FourSeven.php
index cbfbc839a7..abe4aa6599 100644
--- a/CRM/Upgrade/Incremental/php/FourSeven.php
+++ b/CRM/Upgrade/Incremental/php/FourSeven.php
@@ -1093,13 +1093,16 @@ FROM `civicrm_dashboard_contact` JOIN `civicrm_contact` WHERE civicrm_dashboard_
     if ($count = 1) {
       CRM_Core_DAO::executeQuery("UPDATE civicrm_sms_provider SET domain_id = (SELECT id FROM civicrm_domain)");
     }
-    CRM_Core_DAO::executeQuery("SET FOREIGN_KEY_CHECKS = 0;");
-    CRM_Core_DAO::executeQuery("ALTER TABLE `civicrm_sms_provider`
-      ADD CONSTRAINT FK_civicrm_sms_provider_domain_id
-      FOREIGN KEY (`domain_id`) REFERENCES `civicrm_domain`(`id`)
-      ON DELETE SET NULL");
+    $check = CRM_Core_BAO_SchemaHandler::checkFKExists('civicrm_sms_provider', 'FK_civicrm_sms_provider_domain_id');
+    if (!$check) {
+      CRM_Core_DAO::executeQuery("SET FOREIGN_KEY_CHECKS = 0;");
+      CRM_Core_DAO::executeQuery("ALTER TABLE `civicrm_sms_provider`
+        ADD CONSTRAINT FK_civicrm_sms_provider_domain_id
+        FOREIGN KEY (`domain_id`) REFERENCES `civicrm_domain`(`id`)
+        ON DELETE SET NULL");
 
-    CRM_Core_DAO::executeQuery("SET FOREIGN_KEY_CHECKS = 1;");
+      CRM_Core_DAO::executeQuery("SET FOREIGN_KEY_CHECKS = 1;");
+    }
     return TRUE;
   }
 
@@ -1126,22 +1129,8 @@ FROM `civicrm_dashboard_contact` JOIN `civicrm_contact` WHERE civicrm_dashboard_
    * CRM-19986 fix schema differnces in civicrm_action_schedule
    */
   public static function fixSchemaOnCiviCRMActionSchedule() {
-    $config = CRM_Core_Config::singleton();
-    $dbUf = DB::parseDSN($config->dsn);
-    $query = "
-      SELECT CONSTRAINT_NAME FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS
-      WHERE TABLE_SCHEMA = %1
-      AND TABLE_NAME = %2
-      AND CONSTRAINT_NAME = %3
-      AND CONSTRAINT_TYPE = 'FOREIGN KEY'
-    ";
-    $params = array(
-      1 => array($dbUf['database'], 'String'),
-      2 => array('civicrm_action_schedule', 'String'),
-      3 => array('FK_civicrm_action_schedule_sms_template_id', 'String'),
-    );
-    $dao = CRM_Core_DAO::executeQuery($query, $params);
-    if (!$dao->fetch()) {
+    $check = CRM_Core_BAO_SchemaHandler::checkFKExists('civicrm_action_schedule', 'FK_civicrm_action_schedule_sms_template_id');
+    if (!$check) {
       CRM_Core_DAO::executeQuery("ALTER TABLE `civicrm_action_schedule`
         ADD CONSTRAINT FK_civicrm_action_schedule_sms_template_id
         FOREIGN KEY (`sms_template_id`)  REFERENCES `civicrm_msg_template`(`id`)
-- 
2.25.1