searxng/searx/plugins/oa_doi_rewrite.py
Markus Heiser 50f92779bd [refactor] migrate plugins from "module" to class SXNGPlugin
This patch brings two major changes:

- ``Result.filter_urls(..)`` to pass a filter function for URL fields
- The ``enabled_plugins:`` section in SearXNG's settings do no longer exists.

To understand plugin development compile documentation:

    $ make docs.clean docs.live

and read http://0.0.0.0:8000/dev/plugins/development.html

There is no longer a distinction between built-in and external plugin, all
plugins are registered via the settings in the ``plugins:`` section.

In SearXNG, plugins can be registered via a fully qualified class name.  A
configuration (`PluginCfg`) can be transferred to the plugin, e.g. to activate
it by default / *opt-in* or *opt-out* from user's point of view.

built-in plugins
================

The built-in plugins are all located in the namespace `searx.plugins`.

.. code:: yaml

    plugins:

      searx.plugins.calculator.SXNGPlugin:
        active: true

      searx.plugins.hash_plugin.SXNGPlugin:
        active: true

      searx.plugins.self_info.SXNGPlugin:
        active: true

      searx.plugins.tracker_url_remover.SXNGPlugin:
        active: true

      searx.plugins.unit_converter.SXNGPlugin:
        active: true

      searx.plugins.ahmia_filter.SXNGPlugin:
        active: true

      searx.plugins.hostnames.SXNGPlugin:
        active: true

      searx.plugins.oa_doi_rewrite.SXNGPlugin:
        active: false

      searx.plugins.tor_check.SXNGPlugin:
        active: false

external plugins
================

SearXNG supports *external plugins* / there is no need to install one, SearXNG
runs out of the box.

- Only show green hosted results: https://github.com/return42/tgwf-searx-plugins/

To get a developer installation in a SearXNG developer environment:

.. code:: sh

   $ git clone git@github.com:return42/tgwf-searx-plugins.git
   $ ./manage pyenv.cmd python -m \
         pip install -e tgwf-searx-plugins

To register the plugin in SearXNG add ``only_show_green_results.SXNGPlugin`` to
the ``plugins:``:

.. code:: yaml

    plugins:
      # ...
      only_show_green_results.SXNGPlugin:
        active: false

Result.filter_urls(..)
======================

The ``Result.filter_urls(..)`` can be used to filter and/or modify URL fields.
In the following example, the filter function ``my_url_filter``:

.. code:: python

   def my_url_filter(result, field_name, url_src) -> bool | str:
       if "google" in url_src:
           return False              # remove URL field from result
       if "facebook" in url_src:
           new_url = url_src.replace("facebook", "fb-dummy")
           return new_url            # return modified URL
       return True                   # leave URL in field unchanged

is applied to all URL fields in the :py:obj:`Plugin.on_result` hook:

.. code:: python

   class MyUrlFilter(Plugin):
       ...
       def on_result(self, request, search, result) -> bool:
           result.filter_urls(my_url_filter)
           return True

Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>
2025-03-29 10:16:43 +01:00

91 lines
2.7 KiB
Python

# SPDX-License-Identifier: AGPL-3.0-or-later
# pylint: disable=missing-module-docstring
from __future__ import annotations
import typing
import re
from urllib.parse import parse_qsl
from flask_babel import gettext
from searx import get_setting
from searx.plugins import Plugin, PluginInfo
from searx.extended_types import sxng_request
from ._core import log
if typing.TYPE_CHECKING:
from searx.search import SearchWithPlugins
from searx.extended_types import SXNG_Request
from searx.result_types import Result, LegacyResult
from searx.plugins import PluginCfg
ahmia_blacklist: list = []
def filter_url_field(result: "Result|LegacyResult", field_name: str, url_src: str) -> bool | str:
"""Returns bool ``True`` to use URL unchanged (``False`` to ignore URL).
If URL should be modified, the returned string is the new URL to use."""
if field_name != "url":
return True # use it unchanged
doi = extract_doi(result.parsed_url)
if doi and len(doi) < 50:
for suffix in ("/", ".pdf", ".xml", "/full", "/meta", "/abstract"):
doi = doi.removesuffix(suffix)
new_url = get_doi_resolver() + doi
if "doi" not in result:
result["doi"] = doi
log.debug("oa_doi_rewrite: [URL field: %s] %s -> %s", field_name, url_src, new_url)
return new_url # use new url
return True # use it unchanged
class SXNGPlugin(Plugin):
"""Avoid paywalls by redirecting to open-access."""
id = "oa_doi_rewrite"
def __init__(self, plg_cfg: "PluginCfg") -> None:
super().__init__(plg_cfg)
self.info = PluginInfo(
id=self.id,
name=gettext("Open Access DOI rewrite"),
description=gettext("Avoid paywalls by redirecting to open-access versions of publications when available"),
preference_section="general",
)
def on_result(
self,
request: "SXNG_Request",
search: "SearchWithPlugins",
result: "Result",
) -> bool: # pylint: disable=unused-argument
if result.parsed_url:
result.filter_urls(filter_url_field)
return True
regex = re.compile(r'10\.\d{4,9}/[^\s]+')
def extract_doi(url):
m = regex.search(url.path)
if m:
return m.group(0)
for _, v in parse_qsl(url.query):
m = regex.search(v)
if m:
return m.group(0)
return None
def get_doi_resolver() -> str:
doi_resolvers = get_setting("doi_resolvers")
selected_resolver = sxng_request.preferences.get_value('doi_resolver')[0]
if selected_resolver not in doi_resolvers:
selected_resolver = get_setting("default_doi_resolver")
return doi_resolvers[selected_resolver]