Source code for mpas_tools.logging

import sys
import logging
import subprocess


[docs]def check_call(args, logger): """ Call the given subprocess with logging to the given logger. Parameters ---------- args : list A list of argument to the subprocess logger : logging.Logger The logger to write output to Raises ------ subprocess.CalledProcessError If the given subprocess exists with nonzero status """ process = subprocess.Popen(args, stdout=subprocess.PIPE, stderr=subprocess.PIPE) stdout, stderr = process.communicate() if stdout: stdout = stdout.decode('utf-8') for line in stdout.split('\n'): logger.info(line) if stderr: stderr = stderr.decode('utf-8') for line in stderr.split('\n'): logger.error(line) if process.returncode != 0: raise subprocess.CalledProcessError(process.returncode, ' '.join(args))
[docs]class LoggingContext(object): """ A context manager for creating a logger or using an existing logger Attributes ---------- logger : logging.Logger A logger that sends output to a log file or stdout/stderr """
[docs] def __init__(self, name, logger=None, log_filename=None): """ If ``logger`` is ``None``, create a new logger either to a log file or stdout/stderr. If ``logger`` is anything else, just set the logger attribute Parameters ---------- name : str A unique name for the logger (e.g. ``__name__`` of the calling module) logger : logging.Logger, optional An existing logger that sends output to a log file or stdout/stderr to be used in this context log_filename : str, optional The name of a file where output should be written. If none is supplied, output goes to stdout/stderr """ self.logger = logger self.name = name self.log_filename = log_filename self.handler = None self.old_stdout = None self.old_stderr = None self.existing_logger = logger is not None
def __enter__(self): if not self.existing_logger: if self.log_filename is not None: # redirect output to a log file logger = logging.getLogger(self.name) handler = logging.FileHandler(self.log_filename) else: logger = logging.getLogger(self.name) handler = logging.StreamHandler(sys.stdout) formatter = MpasFormatter() handler.setFormatter(formatter) logger.addHandler(handler) logger.setLevel(logging.INFO) logger.propagate = False self.logger = logger self.handler = handler if self.log_filename is not None: self.old_stdout = sys.stdout self.old_stderr = sys.stderr sys.stdout = StreamToLogger(logger, logging.INFO) sys.stderr = StreamToLogger(logger, logging.ERROR) return self.logger def __exit__(self, exc_type, exc_val, exc_tb): if not self.existing_logger: if self.old_stdout is not None: self.handler.close() # restore stdout and stderr sys.stdout = self.old_stdout sys.stderr = self.old_stderr # remove the handlers from the logger (probably only necessary if # writeLogFile==False) self.logger.handlers = [] self.stdout = self.original_stdout = sys.stdout self.stderr = self.original_stderr = sys.stderr
class MpasFormatter(logging.Formatter): """ A custom formatter for logging Modified from: https://stackoverflow.com/a/8349076/7728169 https://stackoverflow.com/a/14859558/7728169 """ # Authors # ------- # Xylar Asay-Davis # printing error messages without a prefix because they are sometimes # errors and sometimes only warnings sent to stderr dbg_fmt = "DEBUG: %(module)s: %(lineno)d: %(msg)s" info_fmt = "%(msg)s" err_fmt = info_fmt def __init__(self, fmt=info_fmt): logging.Formatter.__init__(self, fmt) def format(self, record): # Save the original format configured by the user # when the logger formatter was instantiated format_orig = self._fmt # Replace the original format with one customized by logging level if record.levelno == logging.DEBUG: self._fmt = MpasFormatter.dbg_fmt elif record.levelno == logging.INFO: self._fmt = MpasFormatter.info_fmt elif record.levelno == logging.ERROR: self._fmt = MpasFormatter.err_fmt # Call the original formatter class to do the grunt work result = logging.Formatter.format(self, record) # Restore the original format configured by the user self._fmt = format_orig return result class StreamToLogger(object): """ Modified based on code by: https://www.electricmonk.nl/log/2011/08/14/redirect-stdout-and-stderr-to-a-logger-in-python/ Copyright (C) 2011 Ferry Boender License: GPL, see https://www.electricmonk.nl/log/posting-license/ Fake file-like stream object that redirects writes to a logger instance. """ def __init__(self, logger, log_level=logging.INFO): self.logger = logger self.log_level = log_level self.linebuf = '' def write(self, buf): for line in buf.rstrip().splitlines(): self.logger.log(self.log_level, str(line.rstrip())) def flush(self): pass