[IMP] sql_db: allow to customize pg connection's application_name

This is an improvement over commit f6c13d7 in order to allow full
customization of postgresql connection's `application_name`.

In a PID linux namespace the containers processes IDs might not be relevant
for a system administrator and one might want to customize the content of the
`application_name` just like it was possible to do before commit f6c13d7
using the `PGAPPNAME` environment variable.

This commit allows to expose an `ODOO_PGAPPNAME` environment variable whose
content will be interpolated with the PID (optional)

closes odoo/odoo#117921

X-original-commit: a4108eee91f8e9bf82be5a4be4b91bab16baa0df
Signed-off-by: Olivier Dony (odo) <odo@odoo.com>

odoo/sql_db.py

@@ -725,7 +725,11 @@ def connection_info_for(db_or_uri):
     :param str db_or_uri: database name or postgres dsn
     :rtype: (str, dict)
     """
-    app_name = "odoo-%d" % os.getpid()
+    if 'ODOO_PGAPPNAME' in os.environ:
+        # Using manual string interpolation for security reason and trimming at default NAMEDATALEN=63
+        app_name = os.environ['ODOO_PGAPPNAME'].replace('{pid}', str(os.getpid()))[0:63]
+    else:
+        app_name = "odoo-%d" % os.getpid()
     if db_or_uri.startswith(('postgresql://', 'postgres://')):
         # extract db from uri
         us = urls.url_parse(db_or_uri)