Files
DECNET/tests/test_inode_aware_handler.py
anti cb12e7c475 fix: logging handler must not crash its caller on reopen failure
When decnet.system.log is root-owned (e.g. created by a pre-fix 'sudo
decnet deploy') and a subsequent non-root process tries to log, the
InodeAwareRotatingFileHandler raised PermissionError out of emit(),
which propagated up through logger.debug/info and killed the collector's
log stream loop ('log stream ended ... reason=[Errno 13]').

Now matches stdlib behaviour: wrap _open() in try/except OSError and
defer to handleError() on failure. Adds a regression test.

Also: scripts/profile/view.sh 'pyinstrument' keyword was matching
memray-flamegraph-*.html files. Exclude the memray-* prefix.
2026-04-17 14:01:36 -04:00

112 lines
3.4 KiB
Python

"""
Tests for InodeAwareRotatingFileHandler.
Simulates the two scenarios that break plain RotatingFileHandler:
1. External `rm` of the log file
2. External rename (logrotate-style rotation)
In both cases, the next log record must end up in a recreated file on
disk, not the orphaned inode held by the old file descriptor.
"""
import logging
import os
import pytest
from decnet.logging.inode_aware_handler import InodeAwareRotatingFileHandler
def _make_handler(path) -> logging.Handler:
h = InodeAwareRotatingFileHandler(str(path), maxBytes=10_000_000, backupCount=1)
h.setFormatter(logging.Formatter("%(message)s"))
return h
def _record(msg: str) -> logging.LogRecord:
return logging.LogRecord("t", logging.INFO, __file__, 1, msg, None, None)
def test_writes_land_in_file(tmp_path):
path = tmp_path / "app.log"
h = _make_handler(path)
h.emit(_record("hello"))
h.close()
assert path.read_text().strip() == "hello"
def test_reopens_after_unlink(tmp_path):
path = tmp_path / "app.log"
h = _make_handler(path)
h.emit(_record("first"))
os.remove(path) # simulate `rm decnet.system.log`
assert not path.exists()
h.emit(_record("second"))
h.close()
assert path.exists()
assert path.read_text().strip() == "second"
def test_reopens_after_rename(tmp_path):
"""logrotate rename-and-create: the old path is renamed, then we expect
writes to go to a freshly created file at the original path."""
path = tmp_path / "app.log"
h = _make_handler(path)
h.emit(_record("pre-rotation"))
rotated = tmp_path / "app.log.1"
os.rename(path, rotated) # simulate logrotate move
h.emit(_record("post-rotation"))
h.close()
assert rotated.read_text().strip() == "pre-rotation"
assert path.read_text().strip() == "post-rotation"
def test_no_reopen_when_file_is_stable(tmp_path, monkeypatch):
"""Ensure we don't thrash: back-to-back emits must share one FD."""
path = tmp_path / "app.log"
h = _make_handler(path)
h.emit(_record("one"))
fd_before = h.stream.fileno()
h.emit(_record("two"))
fd_after = h.stream.fileno()
assert fd_before == fd_after
h.close()
assert path.read_text().splitlines() == ["one", "two"]
def test_emit_does_not_raise_when_reopen_fails(tmp_path, monkeypatch):
"""A failed reopen must not propagate — it would crash the caller
(observed in the collector worker when decnet.system.log was root-owned
and the collector ran non-root)."""
path = tmp_path / "app.log"
h = _make_handler(path)
h.emit(_record("first"))
os.remove(path) # force reopen on next emit
def boom(*_a, **_kw):
raise PermissionError(13, "Permission denied")
monkeypatch.setattr(h, "_open", boom)
# Swallow the stderr traceback stdlib prints via handleError.
monkeypatch.setattr(h, "handleError", lambda _r: None)
# Must not raise.
h.emit(_record("second"))
def test_rotation_by_size_still_works(tmp_path):
"""maxBytes-triggered rotation must still function on top of the inode check."""
path = tmp_path / "app.log"
h = InodeAwareRotatingFileHandler(str(path), maxBytes=50, backupCount=1)
h.setFormatter(logging.Formatter("%(message)s"))
for i in range(20):
h.emit(_record(f"line-{i:03d}-xxxxxxxxxxxxxxx"))
h.close()
assert path.exists()
assert (tmp_path / "app.log.1").exists()