fix: run on systems with newer setuptools

- Don't use pkg_resources.packaging if installed
version of setuptools doesn't support it

Author: mstyushin

mamonsu/plugins/pgsql/driver/pg8000/core.py

@@ -2,12 +2,16 @@
 from collections import defaultdict, deque
 from datetime import datetime as Datetime
 from decimal import Decimal
-from pkg_resources import packaging
 from hashlib import md5
 from itertools import count, islice
 from struct import Struct
 from warnings import warn
 
+try:
+    from pkg_resources import packaging
+except ImportError:
+    import packaging.version
+
 from mamonsu.plugins.pgsql.driver.pg8000 import converters
 from .exceptions import (
     ArrayContentNotSupportedError, DatabaseError, Error, IntegrityError,

mamonsu/plugins/pgsql/driver/pool.py

@@ -1,6 +1,9 @@
-from pkg_resources import packaging
 from .connection import Connection, ConnectionInfo
 
+try:
+    from pkg_resources import packaging
+except ImportError:
+    import packaging.version
 
 class Pool(object):
     ExcludeDBs = ["template0", "template1"]

mamonsu/plugins/pgsql/memory_leak_diagnostic.py

@@ -4,10 +4,13 @@
 import os
 from .pool import Pooler
 import re
-from pkg_resources import packaging
 import mamonsu.lib.platform as platform
 import posix
 
+try:
+    from pkg_resources import packaging
+except ImportError:
+    import packaging.version
 
 class MemoryLeakDiagnostic(Plugin):
     DEFAULT_CONFIG = {

mamonsu/plugins/pgsql/replication.py

@@ -1,10 +1,14 @@
 # -*- coding: utf-8 -*-
 
 from mamonsu.plugins.pgsql.plugin import PgsqlPlugin as Plugin
-from pkg_resources import packaging
 from .pool import Pooler
 from mamonsu.lib.zbx_template import ZbxTemplate
 
+try:
+    from pkg_resources import packaging
+except ImportError:
+    import packaging.version
+
 NUMBER_NON_ACTIVE_SLOTS = 0