Improve error message for logs.

[pyutils.git] / src / pyutils / files / lockfile.py

diff --git a/src/pyutils/files/lockfile.py b/src/pyutils/files/lockfile.py
index c7b4841e5373779d6c0bc783f7ce6f32270c9273..937c8631b9462bf168eb44b03bba79902918e4c7 100644 (file)
--- a/src/pyutils/files/lockfile.py
+++ b/src/pyutils/files/lockfile.py
@@ -25,15 +25,15 @@ from dataclasses import dataclass
 from typing import Literal, Optional
 
 from pyutils import argparse_utils, config, decorator_utils
-from pyutils.datetimez import datetime_utils
+from pyutils.datetimes import datetime_utils
 
-cfg = config.add_commandline_args(f'Lockfile ({__file__})', 'Args related to lockfiles')
+cfg = config.add_commandline_args(f"Lockfile ({__file__})", "Args related to lockfiles")
 cfg.add_argument(
-    '--lockfile_held_duration_warning_threshold',
+    "--lockfile_held_duration_warning_threshold",
     type=argparse_utils.valid_duration,
     default=datetime.timedelta(60.0),
-    metavar='DURATION',
-    help='If a lock is held for longer than this threshold we log a warning',
+    metavar="DURATION",
+    help="If a lock is held for longer than this threshold we log a warning",
 )
 logger = logging.getLogger(__name__)
 
@@ -123,12 +123,12 @@ class LockFile(contextlib.AbstractContextManager):
                 logger.debug(contents)
                 f.write(contents)
             self.locktime = datetime.datetime.now().timestamp()
-            logger.debug('Success; I own %s.', self.lockfile)
+            logger.debug("Success; I own %s.", self.lockfile)
             self.is_locked = True
             return True
         except OSError:
             pass
-        logger.warning('Couldn\'t acquire %s.', self.lockfile)
+        logger.warning("Couldn't acquire %s.", self.lockfile)
         return False
 
     def acquire_with_retries(
@@ -176,7 +176,8 @@ class LockFile(contextlib.AbstractContextManager):
     def __enter__(self):
         if self.acquire_with_retries():
             return self
-        msg = f"Couldn't acquire {self.lockfile}; giving up."
+        contents = self._get_lockfile_contents()
+        msg = f"Couldn't acquire {self.lockfile} after several attempts.  It's held by pid={contents.pid} ({contents.commandline}).  Giving up."
         logger.warning(msg)
         raise LockFileException(msg)
 
@@ -187,12 +188,12 @@ class LockFile(contextlib.AbstractContextManager):
             if (
                 duration
                 >= config.config[
-                    'lockfile_held_duration_warning_threshold'
+                    "lockfile_held_duration_warning_threshold"
                 ].total_seconds()
             ):
                 # Note: describe duration briefly only does 1s granularity...
                 str_duration = datetime_utils.describe_duration_briefly(int(duration))
-                msg = f'Held {self.lockfile} for {str_duration}'
+                msg = f"Held {self.lockfile} for {str_duration}"
                 logger.warning(msg)
                 warnings.warn(msg, stacklevel=2)
         self.release()
@@ -210,7 +211,7 @@ class LockFile(contextlib.AbstractContextManager):
         if self.override_command:
             cmd = self.override_command
         else:
-            cmd = ' '.join(sys.argv)
+            cmd = " ".join(sys.argv)
         contents = LockFileContents(
             pid=os.getpid(),
             commandline=cmd,
@@ -220,7 +221,7 @@ class LockFile(contextlib.AbstractContextManager):
 
     def _detect_stale_lockfile(self) -> None:
         try:
-            with open(self.lockfile, 'r') as rf:
+            with open(self.lockfile, "r") as rf:
                 lines = rf.readlines()
                 if len(lines) == 1:
                     line = lines[0]
@@ -233,7 +234,7 @@ class LockFile(contextlib.AbstractContextManager):
                         os.kill(contents.pid, 0)
                     except OSError:
                         logger.warning(
-                            'Lockfile %s\'s pid (%d) is stale; force acquiring...',
+                            "Lockfile %s's pid (%d) is stale; force acquiring...",
                             self.lockfile,
                             contents.pid,
                         )
@@ -244,7 +245,7 @@ class LockFile(contextlib.AbstractContextManager):
                         now = datetime.datetime.now().timestamp()
                         if now > contents.expiration_timestamp:
                             logger.warning(
-                                'Lockfile %s\'s expiration time has passed; force acquiring',
+                                "Lockfile %s's expiration time has passed; force acquiring",
                                 self.lockfile,
                             )
                             self.release()