logging: Introduced a supplemental logging rotating handler package.

Co-authored-by: Paul Sokolovsky <pfalcon@users.sourceforge.net>
Co-authored-by: Stefan Lehmann <stlm@posteo.de>
Signed-off-by: Jonah Bron <hi@jonah.id>

python-stdlib/logging-rotating-handler/README.md

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+# Rotating File Logging Handler
+
+Add-on package for [`logging`](../logging/).  Provides a Handler that can rotate
+logging output between multiple files while keeping the total filesize below a
+specified limit.

python-stdlib/logging-rotating-handler/logging/rotating_handler.py

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+import os
+from . import Handler
+
+# Source: https://github.com/pfalcon/pycopy-lib/blob/master/logging/logging/handlers.py
+
+
+def try_remove(fn: str) -> None:
+    """Try to remove a file if it existst."""
+    try:
+        os.remove(fn)
+    except OSError:
+        pass
+
+
+def get_filesize(fn: str) -> int:
+    """Return size of a file."""
+    return os.stat(fn)[6]
+
+
+class RotatingFileHandler(Handler):
+    """A rotating file handler like RotatingFileHandler.
+
+    Compatible with CPythons `logging.handlers.RotatingFileHandler` class.
+    """
+
+    def __init__(self, filename, maxBytes=0, backupCount=0):
+        super().__init__()
+        self.filename = filename
+        self.maxBytes = maxBytes
+        self.backupCount = backupCount
+
+        try:
+            self._counter = get_filesize(self.filename)
+        except OSError:
+            self._counter = 0
+
+    def emit(self, record):
+        """Write to file."""
+        msg = self.formatter.format(record)
+        s_len = len(msg)
+
+        if self.maxBytes and self.backupCount and self._counter + s_len > self.maxBytes:
+            # remove the last backup file if it is there
+            try_remove(self.filename + ".{0}".format(self.backupCount))
+
+            for i in range(self.backupCount - 1, 0, -1):
+                if i < self.backupCount:
+                    try:
+                        os.rename(
+                            self.filename + ".{0}".format(i),
+                            self.filename + ".{0}".format(i + 1),
+                        )
+                    except OSError:
+                        pass
+
+            try:
+                os.rename(self.filename, self.filename + ".1")
+            except OSError:
+                pass
+            self._counter = 0
+
+        with open(self.filename, "a") as f:
+            f.write(msg + "\n")
+
+        self._counter += s_len

python-stdlib/logging-rotating-handler/manifest.py

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+metadata(
+    version="0.7.5",
+    author="Stefan Lehmann, Paul Sokolovsky",
+    description="Rotating file handler for the logging package",
+)
+
+require("logging")
+
+package("logging")