"""Miscellaneous utilities related to logging."""
import sys
import logging
# If any method that creates handlers is called twice (e.g., setup reconfigure or during tests),
# then we need to prevent another one from being created. Since we have multiple loggers now, we
# store them in a dictionary.
_loggers = {}
def _set_handler(logger, handler, level, use_format):
"""
Set the StreamHandler for logger.
Parameters
----------
logger : object
Logger object.
handler : logging handler
handler to add to the logger
level : int
Logging level for this logger. Default is logging.INFO (level 20).
use_format : bool
Set to True to use the openmdao format "Level: message".
"""
# set a format which is simpler for console use
if use_format:
formatter = logging.Formatter('%(levelname)s: %(message)s')
handler.setFormatter(formatter)
handler.setLevel(level)
logger.addHandler(handler)
[docs]def get_logger(name='default_logger', level=logging.INFO, use_format=False,
out_stream='stdout', out_file=None, lock=None):
"""
Return a logger that writes to an I/O stream.
Parameters
----------
name : str
Name of the logger to be returned, will be created if it doesn't exist.
level : int
Logging level for this logger. Default is logging.INFO (level 20).
(applied only when creating a new logger or setting a new stream).
use_format : bool
Set to True to use the openmdao format "Level: message".
(applied only when creating a new logger or setting a new stream).
out_stream : 'stdout', 'stderr' or file-like
Output stream to which logger output will be directed.
out_file : str or None
If not None, add a FileHandler to write to this file.
lock : bool
If True, do not allow the handler to be changed until unlocked.
If False, unlock the handler for the logger.
Returns
-------
<logging.Logger>
Logger that writes to a stream and adheres to requested settings.
"""
if out_stream == 'stdout':
out_stream = sys.stdout
elif out_stream == 'stderr':
out_stream = sys.stderr
if name in _loggers:
# use existing logger
info = _loggers[name]
logger = info['logger']
stream = info['stream']
ofile = info['file']
locked = info['locked']
unlock = lock is False
# redirect log to new stream (if not locked)
if (out_stream != stream or ofile != out_file) and (not locked or unlock):
for handler in logger.handlers:
logger.removeHandler(handler)
if out_stream:
_set_handler(logger, logging.StreamHandler(out_stream), level, use_format)
if out_file:
_set_handler(logger, logging.FileHandler(out_file, mode='w'), level, use_format)
info['stream'] = out_stream
info['file'] = out_file
# update locked status
info['locked'] = lock
else:
# create new logger
logger = logging.getLogger(name)
logger.setLevel(level)
if out_stream:
_set_handler(logger, logging.StreamHandler(out_stream), level, use_format)
if out_file:
_set_handler(logger, logging.FileHandler(out_file, mode='w'), level, use_format)
_loggers[name] = {
'logger': logger,
'stream': out_stream,
'file': out_file,
'locked': lock
}
return logger
[docs]class TestLogger(object):
"""
A logger that saves messages in lists.
Attributes
----------
_msgs : dict
Stores lists of messages under 'error', 'warning', and 'info' keys.
"""
[docs] def __init__(self):
"""
Initialize the message dict.
"""
self._msgs = {'error': [], 'warning': [], 'info': []}
[docs] def error(self, msg):
"""
Collect an error message.
Parameters
----------
msg : str
An error message.
"""
self._msgs['error'].append(msg)
[docs] def warning(self, msg):
"""
Collect a warning message.
Parameters
----------
msg : str
A warning message.
"""
self._msgs['warning'].append(msg)
[docs] def info(self, msg):
"""
Collect an informational message.
Parameters
----------
msg : str
An informational message.
"""
self._msgs['info'].append(msg)
[docs] def get(self, typ):
"""
Return all stored messages of a specific type.
Parameters
----------
typ : str
Type of messages ('error', 'warning', 'info') to be returned.
Returns
-------
list of str
Any messages of that type that have been written to the logger.
"""
return self._msgs[typ]
[docs] def contains(self, typ, message):
"""
Do any of the stored messages of a specific type equal the given message.
Parameters
----------
typ : str
Type of messages ('error', 'warning', 'info') to be returned.
message : str
The message to match.
Returns
-------
bool
True if any of the lines of stored messages of a specific type equal the line.
"""
for s in self._msgs[typ]:
if s == message:
return True
return False
[docs] def find_in(self, typ, message):
"""
Find the given message among the stored messages.
Raises an exception if the given message isn't found.
Parameters
----------
typ : str
Type of messages ('error', 'warning', 'info') to be searched.
message : str
The message to match.
"""
if not self.contains(typ, message):
raise RuntimeError('Message "{}" not found in {}.'.format(message,
',\n'.join(self._msgs[typ])))
