gh-93205: When rotating logs with no namer specified, match whole extension (GH-93224)

ilCatania · web-flow · commit 113687a8381d · 2024-02-21T23:09:06.000+02:00
diff --git a/Lib/logging/handlers.py b/Lib/logging/handlers.py
@@ -369,32 +369,37 @@ def getFilesToDelete(self):
         dirName, baseName = os.path.split(self.baseFilename)
         fileNames = os.listdir(dirName)
         result = []
-        # See bpo-44753: Don't use the extension when computing the prefix.
-        n, e = os.path.splitext(baseName)
-        prefix = n + '.'
-        plen = len(prefix)
-        for fileName in fileNames:
-            if self.namer is None:
-                # Our files will always start with baseName
-                if not fileName.startswith(baseName):
-                    continue
-            else:
+        if self.namer is None:
+            prefix = baseName + '.'
+            plen = len(prefix)
+            for fileName in fileNames:
+                if fileName[:plen] == prefix:
+                    suffix = fileName[plen:]
+                    if self.extMatch.match(suffix):
+                        result.append(os.path.join(dirName, fileName))
+        else:
+            # See bpo-44753: Don't use the extension when computing the prefix.
+            n, e = os.path.splitext(baseName)
+            prefix = n + '.'
+            plen = len(prefix)
+            for fileName in fileNames:
                 # Our files could be just about anything after custom naming, but
                 # likely candidates are of the form
                 # foo.log.DATETIME_SUFFIX or foo.DATETIME_SUFFIX.log
                 if (not fileName.startswith(baseName) and fileName.endswith(e) and
                     len(fileName) > (plen + 1) and not fileName[plen+1].isdigit()):
                     continue
 
-            if fileName[:plen] == prefix:
-                suffix = fileName[plen:]
-                # See bpo-45628: The date/time suffix could be anywhere in the
-                # filename
-                parts = suffix.split('.')
-                for part in parts:
-                    if self.extMatch.match(part):
-                        result.append(os.path.join(dirName, fileName))
-                        break
+                if fileName[:plen] == prefix:
+                    suffix = fileName[plen:]
+                    # See bpo-45628: The date/time suffix could be anywhere in the
+                    # filename
+
+                    parts = suffix.split('.')
+                    for part in parts:
+                        if self.extMatch.match(part):
+                            result.append(os.path.join(dirName, fileName))
+                            break
         if len(result) < self.backupCount:
             result = []
         else:
diff --git a/Lib/test/test_logging.py b/Lib/test/test_logging.py
@@ -6193,6 +6193,43 @@ def test_compute_files_to_delete(self):
                     self.assertTrue(fn.startswith(prefix + '.') and
                                     fn[len(prefix) + 2].isdigit())
 
+    def test_compute_files_to_delete_same_filename_different_extensions(self):
+        # See GH-93205 for background
+        wd = pathlib.Path(tempfile.mkdtemp(prefix='test_logging_'))
+        self.addCleanup(shutil.rmtree, wd)
+        times = []
+        dt = datetime.datetime.now()
+        n_files = 10
+        for _ in range(n_files):
+            times.append(dt.strftime('%Y-%m-%d_%H-%M-%S'))
+            dt += datetime.timedelta(seconds=5)
+        prefixes = ('a.log', 'a.log.b')
+        files = []
+        rotators = []
+        for i, prefix in enumerate(prefixes):
+            backupCount = i+1
+            rotator = logging.handlers.TimedRotatingFileHandler(wd / prefix, when='s',
+                                                                interval=5,
+                                                                backupCount=backupCount,
+                                                                delay=True)
+            rotators.append(rotator)
+            for t in times:
+                files.append('%s.%s' % (prefix, t))
+        # Create empty files
+        for f in files:
+            (wd / f).touch()
+        # Now the checks that only the correct files are offered up for deletion
+        for i, prefix in enumerate(prefixes):
+            backupCount = i+1
+            rotator = rotators[i]
+            candidates = rotator.getFilesToDelete()
+            self.assertEqual(len(candidates), n_files - backupCount)
+            matcher = re.compile(r"^\d{4}-\d{2}-\d{2}_\d{2}-\d{2}-\d{2}(\.\w+)?$")
+            for c in candidates:
+                d, fn = os.path.split(c)
+                self.assertTrue(fn.startswith(prefix))
+                suffix = fn[(len(prefix)+1):]
+                self.assertRegex(suffix, matcher)
 
 def secs(**kw):
     return datetime.timedelta(**kw) // datetime.timedelta(seconds=1)
diff --git a/Misc/NEWS.d/next/Library/2022-05-25-17-49-04.gh-issue-93205.DjhFVR.rst b/Misc/NEWS.d/next/Library/2022-05-25-17-49-04.gh-issue-93205.DjhFVR.rst
@@ -0,0 +1 @@
+Fixed a bug in :class:`logging.handlers.TimedRotatingFileHandler` where multiple rotating handler instances pointing to files with the same name but different extensions would conflict and not delete the correct files.

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1 @@`
	`1`	+Fixed a bug in :class:`logging.handlers.TimedRotatingFileHandler` where multiple rotating handler instances pointing to files with the same name but different extensions would conflict and not delete the correct files.