Fix bug 1833: fix DATA_SOURCE_NAME in mysqld-exporter

Change-Id: I6641aa68aaa920bbe14ca688b984c5591c0ff72d
Signed-off-by: David Garcia <david.garcia@canonical.com>
diff --git a/installers/charm/mysqld-exporter/src/charm.py b/installers/charm/mysqld-exporter/src/charm.py
index 91be02a..46588b9 100755
--- a/installers/charm/mysqld-exporter/src/charm.py
+++ b/installers/charm/mysqld-exporter/src/charm.py
@@ -185,9 +185,9 @@
         self._check_missing_dependencies(config)
 
         data_source = (
-            config.mysql_uri.replace("mysql://", "").split("/")[0]
+            f'{config.mysql_uri.replace("mysql://", "").replace("@", "@(").split("/")[0]})/'
             if config.mysql_uri
-            else f"root:{self.mysql_client.root_password}@{self.mysql_client.host}:{self.mysql_client.port}"
+            else f"root:{self.mysql_client.root_password}@({self.mysql_client.host}:{self.mysql_client.port})/"
         )
 
         # Create Builder for the PodSpec