searxng/searxng_extra/update/update_external_bangs.py
2023-09-18 16:20:27 +02:00

164 lines
4.6 KiB
Python
Executable File

#!/usr/bin/env python
# lint: pylint
# SPDX-License-Identifier: AGPL-3.0-or-later
"""Update :origin:`searx/data/external_bangs.json` using the duckduckgo bangs
(:origin:`CI Update data ... <.github/workflows/data-update.yml>`).
https://duckduckgo.com/newbang loads:
* a javascript which provides the bang version ( https://duckduckgo.com/bv1.js )
* a JSON file which contains the bangs ( https://duckduckgo.com/bang.v260.js for example )
This script loads the javascript, then the bangs.
The javascript URL may change in the future ( for example
https://duckduckgo.com/bv2.js ), but most probably it will requires to update
RE_BANG_VERSION
"""
# pylint: disable=C0116
import json
import re
from os.path import join
import httpx
from searx import searx_dir # pylint: disable=E0401 C0413
from searx.external_bang import LEAF_KEY
# from https://duckduckgo.com/newbang
URL_BV1 = 'https://duckduckgo.com/bv1.js'
RE_BANG_VERSION = re.compile(r'\/bang\.v([0-9]+)\.js')
HTTPS_COLON = 'https:'
HTTP_COLON = 'http:'
def get_bang_url():
response = httpx.get(URL_BV1)
response.raise_for_status()
r = RE_BANG_VERSION.findall(response.text)
return f'https://duckduckgo.com/bang.v{r[0]}.js', r[0]
def fetch_ddg_bangs(url):
response = httpx.get(url)
response.raise_for_status()
return json.loads(response.content.decode())
def merge_when_no_leaf(node):
"""Minimize the number of nodes
``A -> B -> C``
- ``B`` is child of ``A``
- ``C`` is child of ``B``
If there are no ``C`` equals to ``<LEAF_KEY>``, then each ``C`` are merged
into ``A``. For example (5 nodes)::
d -> d -> g -> <LEAF_KEY> (ddg)
-> i -> g -> <LEAF_KEY> (dig)
becomes (3 nodes)::
d -> dg -> <LEAF_KEY>
-> ig -> <LEAF_KEY>
"""
restart = False
if not isinstance(node, dict):
return
# create a copy of the keys so node can be modified
keys = list(node.keys())
for key in keys:
if key == LEAF_KEY:
continue
value = node[key]
value_keys = list(value.keys())
if LEAF_KEY not in value_keys:
for value_key in value_keys:
node[key + value_key] = value[value_key]
merge_when_no_leaf(node[key + value_key])
del node[key]
restart = True
else:
merge_when_no_leaf(value)
if restart:
merge_when_no_leaf(node)
def optimize_leaf(parent, parent_key, node):
if not isinstance(node, dict):
return
if len(node) == 1 and LEAF_KEY in node and parent is not None:
parent[parent_key] = node[LEAF_KEY]
else:
for key, value in node.items():
optimize_leaf(node, key, value)
def parse_ddg_bangs(ddg_bangs):
bang_trie = {}
bang_urls = {}
for bang_definition in ddg_bangs:
# bang_list
bang_url = bang_definition['u']
if '{{{s}}}' not in bang_url:
# ignore invalid bang
continue
bang_url = bang_url.replace('{{{s}}}', chr(2))
# only for the https protocol: "https://example.com" becomes "//example.com"
if bang_url.startswith(HTTPS_COLON + '//'):
bang_url = bang_url[len(HTTPS_COLON) :]
#
if bang_url.startswith(HTTP_COLON + '//') and bang_url[len(HTTP_COLON) :] in bang_urls:
# if the bang_url uses the http:// protocol, and the same URL exists in https://
# then reuse the https:// bang definition. (written //example.com)
bang_def_output = bang_urls[bang_url[len(HTTP_COLON) :]]
else:
# normal use case : new http:// URL or https:// URL (without "https:", see above)
bang_rank = str(bang_definition['r'])
bang_def_output = bang_url + chr(1) + bang_rank
bang_def_output = bang_urls.setdefault(bang_url, bang_def_output)
bang_urls[bang_url] = bang_def_output
# bang name
bang = bang_definition['t']
# bang_trie
t = bang_trie
for bang_letter in bang:
t = t.setdefault(bang_letter, {})
t = t.setdefault(LEAF_KEY, bang_def_output)
# optimize the trie
merge_when_no_leaf(bang_trie)
optimize_leaf(None, None, bang_trie)
return bang_trie
def get_bangs_filename():
return join(join(searx_dir, "data"), "external_bangs.json")
if __name__ == '__main__':
bangs_url, bangs_version = get_bang_url()
print(f'fetch bangs from {bangs_url}')
output = {'version': bangs_version, 'trie': parse_ddg_bangs(fetch_ddg_bangs(bangs_url))}
with open(get_bangs_filename(), 'w', encoding="utf8") as fp:
json.dump(output, fp, ensure_ascii=False, indent=4)