Reset transaction settings to default on transaction end (Fixes #324)

CHANGELOG.md

@@ -5,6 +5,7 @@
 - Fix #321: Boolean settings in presets caused errors when trying to store the preset's addressbooks to the database
 - Fix #322: The refresh time string from admin presets was not converted to seconds, causing errors or wrong values when
   storing the preset's addressbooks to the database
+- Fix #324: Changes not immediately visible with postgresql (delete contact, add/remove contact to/from group)
 
 ## Version 4.0.3 (to 4.0.2)
 

src/Database.php

@@ -124,6 +124,8 @@ public static function endTransaction(): void
                 self::$logger->error("Database::endTransaction ERROR: " . $dbh->is_error());
                 throw new DatabaseException($dbh->is_error());
             }
+
+            $this->resetTransactionSettings();
         } else {
             throw new \Exception("Attempt to commit a transaction while not within a transaction");
         }
@@ -142,6 +144,8 @@ public static function rollbackTransaction(): void
                 self::$logger->error("Database::rollbackTransaction ERROR: " . $dbh->is_error());
                 throw new \Exception($dbh->is_error());
             }
+
+            $this->resetTransactionSettings();
         } else {
             // not throwing an error here facilitates usage of the interface at caller side. The caller
             // can issue rollback without having to keep track whether an error occurred before/after a
@@ -150,6 +154,29 @@ public static function rollbackTransaction(): void
         }
     }
 
+    /**
+     * Resets database transaction settings to defaults that should apply to autocommit transactions.
+     */
+    private function resetTransactionSettings(): void
+    {
+        $logger = $this->logger;
+        $dbh = $this->dbHandle;
+        switch ($dbh->db_provider) {
+            case "postgres":
+                $ret = $dbh->query(
+                    "SET SESSION CHARACTERISTICS AS TRANSACTION ISOLATION LEVEL REPEATABLE READ, READ WRITE"
+                );
+                break;
+            default:
+                return;
+        }
+
+        // reset default session characteristics to read/write for autocommit single-statement transactions
+        if ($ret === false) {
+            $logger->warning(__METHOD__ . " ERROR: " . $dbh->is_error());
+        }
+    }
+
     /**
      * Checks if the database schema is up to date and performs migrations if needed.
      *