More cleanup, yey!

[python_utils.git] / lockfile.py

diff --git a/lockfile.py b/lockfile.py
index 290710759dbc702fff757ae2561fe5c0af3051a6..6993cb84d5e88f8dd6fc1a9d28a849f0cfd28713 100644 (file)
--- a/lockfile.py
+++ b/lockfile.py
@@ -1,5 +1,7 @@
 #!/usr/bin/env python3
 
+"""File-based locking helper."""
+
 import datetime
 import json
 import logging
@@ -26,11 +28,15 @@ logger = logging.getLogger(__name__)
 
 
 class LockFileException(Exception):
+    """An exception related to lock files."""
+
     pass
 
 
 @dataclass
 class LockFileContents:
+    """The contents we'll write to each lock file."""
+
     pid: int
     commandline: str
     expiration_timestamp: Optional[float]
@@ -56,9 +62,10 @@ class LockFile(object):
         expiration_timestamp: Optional[float] = None,
         override_command: Optional[str] = None,
     ) -> None:
-        self.is_locked = False
-        self.lockfile = lockfile_path
-        self.override_command = override_command
+        self.is_locked: bool = False
+        self.lockfile: str = lockfile_path
+        self.locktime: Optional[int] = None
+        self.override_command: Optional[str] = override_command
         if do_signal_cleanup:
             signal.signal(signal.SIGINT, self._signal)
             signal.signal(signal.SIGTERM, self._signal)
@@ -71,7 +78,7 @@ class LockFile(object):
         return not os.path.exists(self.lockfile)
 
     def try_acquire_lock_once(self) -> bool:
-        logger.debug(f"Trying to acquire {self.lockfile}.")
+        logger.debug("Trying to acquire %s.", self.lockfile)
         try:
             # Attempt to create the lockfile.  These flags cause
             # os.open to raise an OSError if the file already
@@ -81,13 +88,12 @@ class LockFile(object):
                 contents = self._get_lockfile_contents()
                 logger.debug(contents)
                 f.write(contents)
-            logger.debug(f'Success; I own {self.lockfile}.')
+            logger.debug('Success; I own %s.', self.lockfile)
             self.is_locked = True
             return True
         except OSError:
             pass
-        msg = f'Could not acquire {self.lockfile}.'
-        logger.warning(msg)
+        logger.warning('Couldn\'t acquire %s.', self.lockfile)
         return False
 
     def acquire_with_retries(
@@ -125,7 +131,7 @@ class LockFile(object):
         logger.warning(msg)
         raise LockFileException(msg)
 
-    def __exit__(self, type, value, traceback):
+    def __exit__(self, _, value, traceback):
         if self.locktime:
             ts = datetime.datetime.now().timestamp()
             duration = ts - self.locktime
@@ -164,7 +170,7 @@ class LockFile(object):
                     line = lines[0]
                     line_dict = json.loads(line)
                     contents = LockFileContents(**line_dict)
-                    logger.debug(f'Blocking lock contents="{contents}"')
+                    logger.debug('Blocking lock contents="%s"', contents)
 
                     # Does the PID exist still?
                     try: