Log locals on any logging.exception() call

gistfile1.py

import pprint

MAX_VARS_LINES = 30
MAX_LINE_LENGTH = 100


class VerboseExceptionFormatter(logging.Formatter, object):

    def __init__(self, log_locals_on_exception=True, *args, **kwargs):
        self._log_locals = log_locals_on_exception
        super(VerboseExceptionFormatter, self).__init__(*args, **kwargs)

    def formatException(self, exc_info):
        # First get the original formatted exception.
        exc_text = super(VerboseExceptionFormatter, self).formatException(exc_info)
        if not self._log_locals:
            return exc_text
        # Now we're going to format and add the locals information.
        output_lines = [exc_text, '\n']
        tb = exc_info[2]  # This is the outermost frame of the traceback.
        while tb.tb_next:
            tb = tb.tb_next  # Zoom to the innermost frame.
        output_lines.append('Locals at innermost frame:\n')
        locals_text = pprint.pformat(tb.tb_frame.f_locals, indent=2)
        locals_lines = locals_text.split('\n')
        if len(locals_lines) > MAX_VARS_LINES:
            locals_lines = locals_lines[:MAX_VARS_LINES]
            locals_lines[-1] = '...'
        output_lines.extend(
            line[:MAX_LINE_LENGTH - 3] + '...' if len(line) > MAX_LINE_LENGTH else line
            for line in locals_lines)
        output_lines.append('\n')
        return '\n'.join(output_lines)