# SPDX-License-Identifier: AGPL-3.0-or-later
""" Calculate mathematical expressions using ack#eval
"""
import re
import sys
import subprocess
from pathlib import Path
import flask
import babel
from flask_babel import gettext
from searx . plugins import logger
name = " Basic Calculator "
description = gettext ( " Calculate mathematical expressions via the search bar " )
default_on = True
preference_section = ' general '
plugin_id = ' calculator '
logger = logger . getChild ( plugin_id )
def call_calculator ( query_py_formatted , timeout ) :
calculator_process_py_path = Path ( __file__ ) . parent . absolute ( ) / " calculator_process.py "
# see https://docs.python.org/3/using/cmdline.html
# -S Disable the import of the module site and the site-dependent manipulations
# of sys.path that it entails. Also disable these manipulations if site is
# explicitly imported later (call site.main() if you want them to be triggered).
# -I Run Python in isolated mode. This also implies -E, -P and -s options.
# -E Ignore all PYTHON* environment variables, e.g. PYTHONPATH and PYTHONHOME, that might be set.
# -P Don’
# -s Don’
process = subprocess . Popen ( # pylint: disable=R1732
[ sys . executable , " -S " , " -I " , calculator_process_py_path , query_py_formatted ] ,
stdout = subprocess . PIPE ,
stderr = subprocess . PIPE ,
text = True ,
)
try :
stdout , stderr = process . communicate ( timeout = timeout )
if process . returncode == 0 and not stderr :
return stdout
logger . debug ( " calculator exited with stderr %s " , stderr )
return None
except subprocess . TimeoutExpired :
process . terminate ( )
try :
# Give the process a grace period to terminate
process . communicate ( timeout = 2 )
except subprocess . TimeoutExpired :
# Forcefully kill the process
process . kill ( )
process . communicate ( )
logger . debug ( " calculator terminated after timeout " )
# Capture any remaining output
return None
finally :
# Ensure the process is fully cleaned up
if process . poll ( ) is None : # If still running
process . kill ( )
process . communicate ( )
def post_search ( _request , search ) :
# only show the result of the expression on the first page
if search . search_query . pageno > 1 :
return True
query = search . search_query . query
# in order to avoid DoS attacks with long expressions, ignore long expressions
if len ( query ) > 100 :
return True
# replace commonly used math operators with their proper Python operator
query = query . replace ( " x " , " * " ) . replace ( " : " , " / " )
# use UI language
ui_locale = babel . Locale . parse ( flask . request . preferences . get_value ( ' locale ' ) , sep = ' - ' )
# parse the number system in a localized way
def _decimal ( match : re . Match ) - > str :
val = match . string [ match . start ( ) : match . end ( ) ]
val = babel . numbers . parse_decimal ( val , ui_locale , numbering_system = " latn " )
return str ( val )
decimal = ui_locale . number_symbols [ " latn " ] [ " decimal " ]
group = ui_locale . number_symbols [ " latn " ] [ " group " ]
query = re . sub ( f " [0-9]+[ { decimal } | { group } ][0-9]+[ { decimal } | { group } ]?[0-9]? " , _decimal , query )
# only numbers and math operators are accepted
if any ( str . isalpha ( c ) for c in query ) :
return True
# in python, powers are calculated via **
query_py_formatted = query . replace ( " ^ " , " ** " )
# Prevent the runtime from being longer than 50 ms
result = call_calculator ( query_py_formatted , 0.05 )
if result is None or result == " " :
return True
result = babel . numbers . format_decimal ( result , locale = ui_locale )
search . result_container . answers [ ' calculate ' ] = { ' answer ' : f " { search . search_query . query } = { result } " }
return True