Source code for searx.engines

# SPDX-License-Identifier: AGPL-3.0-or-later
# lint: pylint
"""Load and initialize the ``engines``, see :py:func:`load_engines` and register


    load_engines( settings['engines'] )


from __future__ import annotations

import sys
import copy
from os.path import realpath, dirname

from typing import TYPE_CHECKING, Dict
import types
import inspect

from searx import logger, settings
from searx.utils import load_module

    from searx.enginelib import Engine

logger = logger.getChild('engines')
ENGINE_DIR = dirname(realpath(__file__))
    # Common options in the engine module
    "engine_type": "online",
    "paging": False,
    "time_range_support": False,
    "safesearch": False,
    # settings.yml
    "categories": ["general"],
    "enable_http": False,
    "shortcut": "-",
    "timeout": settings["outgoing"]["request_timeout"],
    "display_error_messages": True,
    "disabled": False,
    "inactive": False,
    "about": {},
    "using_tor_proxy": False,
    "send_accept_language_header": False,
    "tokens": [],
# set automatically when an engine does not have any tab category

# Defaults for the namespace of an engine module, see :py:func:`load_engine`

categories = {'general': []}
engines: Dict[str, Engine | types.ModuleType] = {}
engine_shortcuts = {}
"""Simple map of registered *shortcuts* to name of the engine (or ``None``).


    engine_shortcuts[engine.shortcut] =

:meta hide-value:

def check_engine_module(module: types.ModuleType):
    # probe unintentional name collisions / for example name collisions caused
    # by import statements in the engine module ..

    # network:
    obj = getattr(module, 'network', None)
    if obj and inspect.ismodule(obj):
        msg = f'type of {module.__name__}.network is a module ({obj.__name__}), expected a string'
        # logger.error(msg)
        raise TypeError(msg)

[docs] def load_engine(engine_data: dict) -> Engine | types.ModuleType | None: """Load engine from ``engine_data``. :param dict engine_data: Attributes from YAML ``settings:engines/<engine>`` :return: initialized namespace of the ``<engine>``. 1. create a namespace and load module of the ``<engine>`` 2. update namespace with the defaults from :py:obj:`ENGINE_DEFAULT_ARGS` 3. update namespace with values from ``engine_data`` If engine *is active*, return namespace of the engine, otherwise return ``None``. This function also returns ``None`` if initialization of the namespace fails for one of the following reasons: - engine name contains underscore - engine name is not lowercase - required attribute is not set :py:func:`is_missing_required_attributes` """ # pylint: disable=too-many-return-statements engine_name = engine_data.get('name') if engine_name is None: logger.error('An engine does not have a "name" field') return None if '_' in engine_name: logger.error('Engine name contains underscore: "{}"'.format(engine_name)) return None if engine_name.lower() != engine_name: logger.warning('Engine name is not lowercase: "{}", converting to lowercase'.format(engine_name)) engine_name = engine_name.lower() engine_data['name'] = engine_name # load_module module_name = engine_data.get('engine') if module_name is None: logger.error('The "engine" field is missing for the engine named "{}"'.format(engine_name)) return None try: engine = load_module(module_name + '.py', ENGINE_DIR) except (SyntaxError, KeyboardInterrupt, SystemExit, SystemError, ImportError, RuntimeError): logger.exception('Fatal exception in engine "{}"'.format(module_name)) sys.exit(1) except BaseException: logger.exception('Cannot load engine "{}"'.format(module_name)) return None check_engine_module(engine) update_engine_attributes(engine, engine_data) update_attributes_for_tor(engine) # avoid cyclic imports # pylint: disable=import-outside-toplevel from searx.enginelib.traits import EngineTraitsMap trait_map = EngineTraitsMap.from_data() trait_map.set_traits(engine) if not is_engine_active(engine): return None if is_missing_required_attributes(engine): return None set_loggers(engine, engine_name) if not any(cat in settings['categories_as_tabs'] for cat in engine.categories): engine.categories.append(DEFAULT_CATEGORY) return engine
def set_loggers(engine, engine_name): # set the logger for engine engine.logger = logger.getChild(engine_name) # the engine may have load some other engines # may sure the logger is initialized # use sys.modules.copy() to avoid "RuntimeError: dictionary changed size during iteration" # see # and modules = sys.modules.copy() for module_name, module in modules.items(): if ( module_name.startswith("searx.engines") and module_name != "searx.engines.__init__" and not hasattr(module, "logger") ): module_engine_name = module_name.split(".")[-1] module.logger = logger.getChild(module_engine_name) # type: ignore def update_engine_attributes(engine: Engine | types.ModuleType, engine_data): # set engine attributes from engine_data for param_name, param_value in engine_data.items(): if param_name == 'categories': if isinstance(param_value, str): param_value = list(map(str.strip, param_value.split(','))) engine.categories = param_value # type: ignore elif hasattr(engine, 'about') and param_name == 'about': engine.about = {**engine.about, **engine_data['about']} # type: ignore else: setattr(engine, param_name, param_value) # set default attributes for arg_name, arg_value in ENGINE_DEFAULT_ARGS.items(): if not hasattr(engine, arg_name): setattr(engine, arg_name, copy.deepcopy(arg_value)) def update_attributes_for_tor(engine: Engine | types.ModuleType): if using_tor_proxy(engine) and hasattr(engine, 'onion_url'): engine.search_url = engine.onion_url + getattr(engine, 'search_path', '') # type: ignore engine.timeout += settings['outgoing'].get('extra_proxy_timeout', 0) # type: ignore
[docs] def is_missing_required_attributes(engine): """An attribute is required when its name doesn't start with ``_`` (underline). Required attributes must not be ``None``. """ missing = False for engine_attr in dir(engine): if not engine_attr.startswith('_') and getattr(engine, engine_attr) is None: logger.error('Missing engine config attribute: "{0}.{1}"'.format(, engine_attr)) missing = True return missing
[docs] def using_tor_proxy(engine: Engine | types.ModuleType): """Return True if the engine configuration declares to use Tor.""" return settings['outgoing'].get('using_tor_proxy') or getattr(engine, 'using_tor_proxy', False)
def is_engine_active(engine: Engine | types.ModuleType): # check if engine is inactive if engine.inactive is True: return False # exclude onion engines if not using tor if 'onions' in engine.categories and not using_tor_proxy(engine): return False return True def register_engine(engine: Engine | types.ModuleType): if in engines: logger.error('Engine config error: ambiguous name: {0}'.format( sys.exit(1) engines[] = engine if engine.shortcut in engine_shortcuts: logger.error('Engine config error: ambiguous shortcut: {0}'.format(engine.shortcut)) sys.exit(1) engine_shortcuts[engine.shortcut] = for category_name in engine.categories: categories.setdefault(category_name, []).append(engine)
[docs] def load_engines(engine_list): """usage: ``engine_list = settings['engines']``""" engines.clear() engine_shortcuts.clear() categories.clear() categories['general'] = [] for engine_data in engine_list: engine = load_engine(engine_data) if engine: register_engine(engine) return engines