An escape error of re.py (re.error: bad escape \s at position 0) in "utils/logloader.py" based on Python3.7

[DawNIng-github]

Dear authors,
Thanks for your work. When I ran the file, "MoLFI_demo.py", based on Python3.7, I got the error as following.

Traceback (most recent call last):
  File "~/anaconda3/envs/tf/lib/python3.7/sre_parse.py", line 1021, in parse_template
    this = chr(ESCAPES[this][1])
KeyError: '\\s'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "MoLFI_demo.py", line 14, in <module>
    parser.parse(log_file)
  File "../logparser/MoLFI/MoLFI.py", line 41, in parse
    loader = logloader.LogLoader(self.log_format, self.n_workers)
  File "../logparser/utils/logloader.py", line 38, in __init__
    self.headers, self.regex = self._generate_logformat_regex(self.logformat)
  File "../logparser/utils/logloader.py", line 79, in _generate_logformat_regex
    splitter = re.sub(' +', '\s+', splitters[k])
  File "~/anaconda3/envs/tf/lib/python3.7/re.py", line 192, in sub
    return _compile(pattern, flags).sub(repl, string, count)
  File "~/anaconda3/envs/tf/lib/python3.7/re.py", line 309, in _subx
    template = _compile_repl(template, pattern)
  File "~/anaconda3/envs/tf/lib/python3.7/re.py", line 300, in _compile_repl
    return sre_parse.parse_template(repl, pattern)
  File "~/anaconda3/envs/tf/lib/python3.7/sre_parse.py", line 1024, in parse_template
    raise s.error('bad escape %s' % this, len(this))
re.error: bad escape \s at position 0

I'd be grateful if you could help me.

[zhujiem]

Please use Python 3.6

[ankit-nassa]

You can also try replacing import re to import regex as re

[fuyunliu]

template_regex = re.sub(r'\\ +', r'\s+', template_regex)

what do you mean sub \\ + with \s+ ?

[shoaib-intro]

template_regex = re.sub(r'\\ +', r'\s+', template_regex)

what do you mean sub \\ + with \s+ ?
Hi @fuyunliu
I faced same error bad escape sequence error at this line have you solved it?

[devharsh]

Traceback (most recent call last):

File "/usr/local/Cellar/python@3.9/3.9.12_1/Frameworks/Python.framework/Versions/3.9/lib/python3.9/sre_parse.py", line 1041, in parse_template
this = chr(ESCAPES[this][1])

KeyError: '\s'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):

File "/usr/local/lib/python3.9/site-packages/spyder_kernels/py3compat.py", line 356, in compat_exec
exec(code, globals, locals)

File "/Users/devharsh/Downloads/Drain_demo.py", line 28, in
parser.parse(log_file)

File "/Users/devharsh/Downloads/Drain.py", line 293, in parse
self.outputResult(logCluL)

File "/Users/devharsh/Downloads/Drain.py", line 224, in outputResult
self.df_log["ParameterList"] = self.df_log.apply(self.get_parameter_list, axis=1)

File "/usr/local/lib/python3.9/site-packages/pandas/core/frame.py", line 8839, in apply
return op.apply().finalize(self, method="apply")

File "/usr/local/lib/python3.9/site-packages/pandas/core/apply.py", line 727, in apply
return self.apply_standard()

File "/usr/local/lib/python3.9/site-packages/pandas/core/apply.py", line 851, in apply_standard
results, res_index = self.apply_series_generator()

File "/usr/local/lib/python3.9/site-packages/pandas/core/apply.py", line 867, in apply_series_generator
results[i] = self.f(v)

File "/Users/devharsh/Downloads/Drain.py", line 347, in get_parameter_list
template_regex = re.sub(r'\ +', r'\s+', template_regex)

File "/usr/local/Cellar/python@3.9/3.9.12_1/Frameworks/Python.framework/Versions/3.9/lib/python3.9/re.py", line 210, in sub
return _compile(pattern, flags).sub(repl, string, count)

File "/usr/local/Cellar/python@3.9/3.9.12_1/Frameworks/Python.framework/Versions/3.9/lib/python3.9/re.py", line 327, in _subx
template = _compile_repl(template, pattern)

File "/usr/local/Cellar/python@3.9/3.9.12_1/Frameworks/Python.framework/Versions/3.9/lib/python3.9/re.py", line 318, in _compile_repl
return sre_parse.parse_template(repl, pattern)

File "/usr/local/Cellar/python@3.9/3.9.12_1/Frameworks/Python.framework/Versions/3.9/lib/python3.9/sre_parse.py", line 1044, in parse_template
raise s.error('bad escape %s' % this, len(this))

error: bad escape \s

[devharsh]

error when I changed import re to import regex as re

Traceback (most recent call last):

File "/usr/local/lib/python3.9/site-packages/spyder_kernels/py3compat.py", line 356, in compat_exec
exec(code, globals, locals)

File "/Users/devharsh/Downloads/Drain_demo.py", line 28, in
parser.parse(log_file)

File "/Users/devharsh/Downloads/Drain.py", line 293, in parse
self.outputResult(logCluL)

File "/Users/devharsh/Downloads/Drain.py", line 224, in outputResult
self.df_log["ParameterList"] = self.df_log.apply(self.get_parameter_list, axis=1)

File "/usr/local/lib/python3.9/site-packages/pandas/core/frame.py", line 8839, in apply
return op.apply().finalize(self, method="apply")

File "/usr/local/lib/python3.9/site-packages/pandas/core/apply.py", line 727, in apply
return self.apply_standard()

File "/usr/local/lib/python3.9/site-packages/pandas/core/apply.py", line 851, in apply_standard
results, res_index = self.apply_series_generator()

File "/usr/local/lib/python3.9/site-packages/pandas/core/apply.py", line 867, in apply_series_generator
results[i] = self.f(v)

File "/Users/devharsh/Downloads/Drain.py", line 347, in get_parameter_list
template_regex = re.sub(r'\ +', r'\s+', template_regex)

File "/usr/local/lib/python3.9/site-packages/regex/regex.py", line 278, in sub
return pat.sub(repl, string, count, pos, endpos, concurrent, timeout)

File "/usr/local/lib/python3.9/site-packages/regex/regex.py", line 700, in _compile_replacement_helper
is_group, items = _compile_replacement(source, pattern, is_unicode)

File "/usr/local/lib/python3.9/site-packages/regex/_regex_core.py", line 1737, in _compile_replacement
raise error("bad escape \%s" % ch, source.string, source.pos)

error: bad escape \s

[estebanpw]

Just adding this in case someone else has this problem in 2022 when using python 3.8.10.
I changed the following line:

splitter = re.sub(' +', '\s+', splitters[k])

to

splitter = re.sub(' +', '\\\s+', splitters[k])

and that fixed it. Note that I changed this only in the function def _generate_logformat_regex(self, logformat): of the file Spell/Spell.py (because I was using spell) and not in utils/logloader.py.

[Jun-jie-Huang]

You can also try replacing import re to import regex as re

Try to degrade regex pip install regex=2022.3.2 if it still raises exceptions. This works for me.

[khawar-islam]

Hello @estebanpw I implemented your suggestion but still the problem is same. Any idea how to fix?

[shoaib-intro]

Hello @estebanpw I implemented your suggestion but still the problem is same. Any idea how to fix?

also you can try import regex as re if import throw error use pip install regex but keep @estebanpw Suggestion also this is additional to that.