check postgresql presence before running

tests/test_postgresql.py

@@ -19,8 +19,7 @@ except ImportError:
 
 sys.path.append(str(Path(__file__).parents[1].resolve()))
 
-# pylint: disable=wrong-import-position
-from envsetup import utils as u  # noqa: E402
+import utils as u
 
 
 def is_ha(port: int) -> bool:
@@ -380,6 +379,10 @@ def check_local(db_conn: dict, errors: int = 0) -> int:
 def main():
     """Run all checks and exits with corresponding exit code."""
 
+    apt = u.apt.Apt()
+    if "postgresql" not in apt.installed_packages:
+        exit(2)
+
     # load configuration
     conf = u.load_conf()