code cleanup: dropped python2 support in libs, code formating in libs…

…. min pylint level set to 6

.github/workflows/tests-pull_request.yml

@@ -25,7 +25,7 @@ jobs:
           python -m pip install pylint==2.17.7 pylint_runner flask
       - name: Lint with pyLint
         run: |
-          pylint $(git ls-files '*.py') --fail-under 4
+          pylint $(git ls-files '*.py') --fail-under 6
       - name: Check with Unitests
         run: |
           ./tests.py

.github/workflows/tests-push.yml

@@ -27,7 +27,7 @@ jobs:
           #if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
       - name: Lint with pyLint
         run: |
-          pylint $(git ls-files '*.py') --fail-under 4
+          pylint $(git ls-files '*.py') --fail-under 6
       - name: Check with Unitest
         run: |
           ./tests.py

collectors/lib/docker_engine/docker_metrics.py

@@ -15,9 +15,10 @@
 from __future__ import print_function
 import time
 import requests
-from prometheus_client.parser import text_string_to_metric_families
+from prometheus_client.parser import text_string_to_metric_families  # pylint: disable=import-error
 from collectors.lib.docker_engine.metric import Metric
 
+
 class DockerMetrics(object):
     def __init__(self, url):
         self._url = url

collectors/lib/postgresqlutils.py

@@ -15,61 +15,61 @@
 Collector Utilities for PostgreSQL.
 """
 
-import sys
 import os
-import time
 import socket
-import errno
 
 try:
-  import psycopg2
+    import psycopg2
 except ImportError:
-  psycopg2 = None # handled in main()
+    psycopg2 = None  # handled in main()
 
-CONNECT_TIMEOUT = 2 # seconds
+CONNECT_TIMEOUT = 2  # seconds
 
 from collectors.lib import utils
 from collectors.etc import postgresqlconf
 
 # Directories under which to search socket files
 SEARCH_DIRS = frozenset([
-  "/var/run/postgresql", # Debian default
-  "/var/pgsql_socket", # MacOS default
-  "/usr/local/var/postgres", # custom compilation
-  "/tmp", # custom compilation
+    "/var/run/postgresql",  # Debian default
+    "/var/pgsql_socket",  # MacOS default
+    "/usr/local/var/postgres",  # custom compilation
+    "/tmp",  # custom compilation
 ])
 
+
 def find_sockdir():
-  """Returns a path to PostgreSQL socket file to monitor."""
-  for dir in SEARCH_DIRS:
-    for dirpath, dirnames, dirfiles in os.walk(dir, followlinks=True):
-      for name in dirfiles:
-        # ensure selection of PostgreSQL socket only
-        if (utils.is_sockfile(os.path.join(dirpath, name)) and "PGSQL" in name):
-          return(dirpath)
+    """Returns a path to PostgreSQL socket file to monitor."""
+    for dir in SEARCH_DIRS:
+        for dirpath, dirnames, dirfiles in os.walk(dir, followlinks=True):
+            for name in dirfiles:
+                # ensure selection of PostgreSQL socket only
+                if (utils.is_sockfile(os.path.join(dirpath, name)) and "PGSQL" in name):
+                    return dirpath
+
 
 def postgres_connect(sockdir):
-  """Connects to the PostgreSQL server using the specified socket file."""
-  user, password = postgresqlconf.get_user_password()
+    """Connects to the PostgreSQL server using the specified socket file."""
+    user, password = postgresqlconf.get_user_password()
+
+    try:
+        return psycopg2.connect("host='%s' user='%s' password='%s' "
+                                "connect_timeout='%s' dbname=postgres"
+                                % (sockdir, user, password,
+                                   CONNECT_TIMEOUT))
+    except (EnvironmentError, EOFError, RuntimeError, socket.error) as e:
+        utils.err("Couldn't connect to DB :%s" % (e))
 
-  try:
-    return psycopg2.connect("host='%s' user='%s' password='%s' "
-                            "connect_timeout='%s' dbname=postgres"
-                            % (sockdir, user, password,
-                            CONNECT_TIMEOUT))
-  except (EnvironmentError, EOFError, RuntimeError, socket.error) as e:
-    utils.err("Couldn't connect to DB :%s" % (e))
 
 def connect():
-  """Returns an initialized connection to Postgresql."""
-  if psycopg2 is None:
-    raise RuntimeError("error: Python module 'psycopg2' is missing")
+    """Returns an initialized connection to Postgresql."""
+    if psycopg2 is None:
+        raise RuntimeError("error: Python module 'psycopg2' is missing")
 
-  sockdir = find_sockdir()
-  if not sockdir: # Nothing to monitor
-    raise RuntimeError("error: Can't find postgresql socket file")
+    sockdir = find_sockdir()
+    if not sockdir:  # Nothing to monitor
+        raise RuntimeError("error: Can't find postgresql socket file")
 
-  db = postgres_connect(sockdir)
-  db.autocommit=True
+    db = postgres_connect(sockdir)
+    db.autocommit = True
 
-  return db
+    return db

collectors/lib/utils.py

@@ -1,6 +1,6 @@
 #!/usr/bin/env python
 # This file is part of tcollector.
-# Copyright (C) 2013  The tcollector Authors.
+# Copyright (C) 2013-2024  The tcollector Authors.
 #
 # This program is free software: you can redistribute it and/or modify it
 # under the terms of the GNU Lesser General Public License as published by
@@ -22,8 +22,6 @@
 import errno
 import sys
 
-PY3 = sys.version_info[0] > 2
-
 # If we're running as root and this user exists, we'll drop privileges.
 USER = "nobody"
 
@@ -58,14 +56,5 @@ def err(msg):
     print(msg, file=sys.stderr)
 
 
-if PY3:
-    def is_numeric(value):
-        return isinstance(value, (int, float))
-else:
-    def is_numeric(value):
-        try:
-            float(str(value))
-            return True
-        except ValueError:
-            pass
-        return False
+def is_numeric(value):
+    return isinstance(value, (int, float))

collectors/test/docker_engine/test_docker_metrics.py

@@ -33,5 +33,6 @@ def test_eval_prometheus_line(self):
         provided_line = provided.get_metric_lines()
         self.assertEqual(expected_line, provided_line)
 
+
 if __name__ == '__main__':
     unittest.main()

mocks.py

@@ -17,9 +17,11 @@
 # for debugging
 real_stderr = sys.stderr
 
+
 class SocketDone(Exception):
     pass
 
+
 class Socket():
     def __init__(self):
         self.AF_INET = 0
@@ -42,13 +44,14 @@ def close(self):
             return None
 
         def recvfrom(self, inBytes):
-            if (len(self.state['udp_in']) > 0):
+            if len(self.state['udp_in']) > 0:
                 line = self.state['udp_in'].pop(0)
                 return (line, None)
             else:
                 raise SocketDone('stop reading from socket')
 
-class Sys():
+
+class Sys:
     def __init__(self):
         self.stderr = self.Stderr()
         self.stdout = self.Stdout()
@@ -59,21 +62,22 @@ def exit(self, exitCode):
         msg = 'exit called with code %s\n  stderr: %s\n  trace: %s'
         raise Exception(msg % (exitCode, err, trace))
 
-    class Stderr():
+    class Stderr:
         def __init__(self):
             self.lines = []
 
         def write(self, outString):
             self.lines.append(outString)
 
-    class Stdout():
+    class Stdout:
         def __init__(self):
             self.lines = []
 
         def write(self, outString):
             self.lines.append(outString)
 
-class Utils():
+
+class Utils:
     def __init__(self):
         self.drop_privileges = lambda: None
 

tests.py

@@ -29,9 +29,6 @@
 import tcollector
 
 
-PY3 = sys.version_info[0] > 2
-
-
 def return_none(x):
     return None
 
@@ -113,10 +110,7 @@ def check_access_rights(top):
                 elif S_ISREG(mode):
                     # file, check permissions
                     permissions = oct(os.stat(pathname)[ST_MODE])
-                    if PY3:
-                        self.assertEqual("0o100755", permissions)
-                    else:
-                        self.assertEqual("0100755", permissions)
+                    self.assertEqual("0o100755", permissions)
                 else:
                     # unknown file type
                     pass