Files
fm-orchestrator/module_build_service/common/logger.py
Owen W. Taylor 1c8e2a07d8 Local builds: buffer up initial logs and replay to the module build file
Logging during a build that occurs before the build directory is created
used to be logged to the console, but not retained in the build log
file. This made referring to the build log file confusing. Solve this
by buffering logs in memory until the log file is created and replaying
them.

A little bit of hackery is needed to avoid saving dangling references to
libsolv objects.
2023-03-07 18:33:30 +00:00

289 lines
8.3 KiB
Python

# -*- coding: utf-8 -*-
# SPDX-License-Identifier: MIT
"""
Logging functions.
At the beginning of the MBS flow, init_logging(conf) must be called.
After that, logging from any module is possible using Python's "logging"
module as showed at
<https://docs.python.org/3/howto/logging.html#logging-basic-tutorial>.
Examples:
import logging
logging.debug("Phasers are set to stun.")
logging.info("%s tried to build something", username)
logging.warning("%s failed to build", task_id)
"""
from __future__ import absolute_import
import os
import logging
import logging.handlers
import inspect
levels = {
"debug": logging.DEBUG,
"error": logging.ERROR,
"warning": logging.WARNING,
"info": logging.INFO,
}
level_flags = {
"debug": levels["debug"],
"verbose": levels["info"],
"quiet": levels["error"],
}
log_format = "%(asctime)s - %(threadName)s - %(name)s - %(levelname)s - %(message)s"
class ModuleBuildFileHandler(logging.FileHandler):
"""
FileHandler subclass which handles only messages generated during
particular module build with `build_id` set in its constructor.
"""
def __init__(self, build_id, filename, mode="a", encoding=None, delay=0):
logging.FileHandler.__init__(self, filename, mode, encoding, delay)
self.build_id = build_id
def emit(self, record):
# Imported here because of importing cycle between __init__.py,
# scheduler and models.
from module_build_service.scheduler.consumer import MBSConsumer
# Check the currently handled module build and emit the message only
# if it's associated with current module.
build_id = MBSConsumer.current_module_build_id
if not build_id or build_id != self.build_id:
return
logging.FileHandler.emit(self, record)
def _is_solv_object(o):
"""
Returns true if the object is a libsolv object or contains one.
(Contains is implemented pragmatically and might need to be extended)
"""
if isinstance(o, (tuple, list)):
return any(_is_solv_object(x) for x in o)
else:
return str(type(o)).startswith("<class 'solv.")
class _ReprString(str):
"""
String that doesn't add quotes for repr()
"""
def __repr__(self):
return self
class ModuleBuildInitialHandler(logging.handlers.MemoryHandler):
"""
MemoryHandler subclass that never flushes - we use this to record initial log
messages for a Mock build so that we can write them into the build logs for
the module or modules.
"""
def __init__(self):
logging.handlers.MemoryHandler.__init__(self, 0, flushOnClose=False)
def handle(self, record):
# Python libsolv proxies don't actually reference the underlying object
# and keep it from being destroyed, so we need to avoid saving them
# in record.args
if any(_is_solv_object(a) for a in record.args):
record.args = tuple(_ReprString(a) if _is_solv_object(a) else a for a in record.args)
logging.handlers.MemoryHandler.handle(self, record)
def shouldFlush(self, record):
return False
class ModuleBuildLogs(object):
"""
Manages ModuleBuildFileHandler logging handlers.
"""
def __init__(self, build_logs_dir, build_logs_name_format, level=logging.INFO):
"""
Creates new ModuleBuildLogs instance. Module build logs are stored
to `build_logs_dir` directory.
"""
self.initial_handler = None
self.initial_logs = []
self.handlers = {}
self.build_logs_dir = build_logs_dir
self.build_logs_name_format = build_logs_name_format
self.level = level
def path(self, db_session, build):
"""
Returns the full path to build log of module with id `build_id`.
"""
path = os.path.join(self.build_logs_dir, self.name(db_session, build))
return path
def name(self, db_session, build):
"""
Returns the filename for a module build
"""
name = self.build_logs_name_format.format(**build.json(db_session))
return name
def buffer_initially(self):
"""
Starts saving messages before builds start - these messages will be
added to all build logs
"""
handler = ModuleBuildInitialHandler()
handler.setLevel(self.level)
log = logging.getLogger()
log.setLevel(self.level)
log.addHandler(handler)
self.initial_handler = handler
def start(self, db_session, build):
"""
Starts logging build log for module with `build_id` id.
"""
if not self.build_logs_dir:
return
log = logging.getLogger()
# We've finished recording the initial setup logs that we replay
# to all the build logs.
if self.initial_handler:
log = logging.getLogger()
self.initial_logs = self.initial_handler.buffer
log.removeHandler(self.initial_handler)
self.initial_handler = None
if build.id in self.handlers:
return
# Create and add ModuleBuildFileHandler.
handler = ModuleBuildFileHandler(build.id, self.path(db_session, build))
handler.setLevel(self.level)
handler.setFormatter(logging.Formatter(log_format, None))
log.setLevel(self.level)
log.addHandler(handler)
# Replay the initial logs to this handler
for record in self.initial_logs:
handler.handle(record)
self.handlers[build.id] = handler
def stop(self, build):
"""
Stops logging build log for module with `build_id` id. It does *not*
remove the build log from fs.
"""
if build.id not in self.handlers:
return
handler = self.handlers[build.id]
handler.flush()
handler.close()
# Remove the log handler.
log = logging.getLogger()
log.removeHandler(handler)
del self.handlers[build.id]
class MBSLogger:
def __init__(self):
self._logger = logging.getLogger("MBS")
self._level = logging.NOTSET
self._current_path = os.path.dirname(os.path.realpath(__file__))
@property
def logger(self):
return self._logger
@property
def level(self):
return self._level
@level.setter
def level(self, level):
self._level = level
self.logger.setLevel(self._level)
def setLevel(self, level):
self.level = level
def debug(self, *args, **kwargs):
return self._log_call("debug", args, kwargs)
def info(self, *args, **kwargs):
return self._log_call("info", args, kwargs)
def warning(self, *args, **kwargs):
return self._log_call("warning", args, kwargs)
def error(self, *args, **kwargs):
return self._log_call("error", args, kwargs)
def critical(self, *args, **kwargs):
return self._log_call("critical", args, kwargs)
def exception(self, *args, **kwargs):
return self._log_call("exception", args, kwargs)
def log(self, *args, **kwargs):
return self._log_call("log", args, kwargs)
def _log_call(self, level_name, args, kwargs):
caller_filename = inspect.stack()[2][1]
caller_filename = os.path.normpath(caller_filename)
if not caller_filename.startswith(self._current_path):
log_name = "MBS"
else:
log_name = "MBS" + caller_filename[len(self._current_path):-3].replace("/", ".")
return getattr(logging.getLogger(log_name), level_name)(*args, **kwargs)
def str_to_log_level(level):
"""
Returns internal representation of logging level defined
by the string `level`.
Available levels are: debug, info, warning, error
"""
if level not in levels:
return logging.NOTSET
return levels[level]
def supported_log_backends():
return ("console", "file")
def init_logging(conf):
"""
Initializes logging according to configuration file.
"""
log_backend = conf.log_backend
if not log_backend or len(log_backend) == 0 or log_backend == "console":
logging.basicConfig(level=conf.log_level, format=log_format)
log = MBSLogger()
log.level = conf.log_level
else:
logging.basicConfig(filename=conf.log_file, level=conf.log_level, format=log_format)
log = MBSLogger()