first commit

searx/external_bang.py

@@ -0,0 +1,100 @@
+# SPDX-License-Identifier: AGPL-3.0-or-later
+# pylint: disable=missing-module-docstring
+
+from urllib.parse import quote_plus, urlparse
+from searx.data import EXTERNAL_BANGS
+
+LEAF_KEY = chr(16)
+
+
+def get_node(external_bangs_db, bang):
+    node = external_bangs_db['trie']
+    after = ''
+    before = ''
+    for bang_letter in bang:
+        after += bang_letter
+        if after in node and isinstance(node, dict):
+            node = node[after]
+            before += after
+            after = ''
+    return node, before, after
+
+
+def get_bang_definition_and_ac(external_bangs_db, bang):
+    node, before, after = get_node(external_bangs_db, bang)
+
+    bang_definition = None
+    bang_ac_list = []
+    if after != '':
+        for k in node:
+            if k.startswith(after):
+                bang_ac_list.append(before + k)
+    elif isinstance(node, dict):
+        bang_definition = node.get(LEAF_KEY)
+        bang_ac_list = [before + k for k in node.keys() if k != LEAF_KEY]
+    elif isinstance(node, str):
+        bang_definition = node
+        bang_ac_list = []
+
+    return bang_definition, bang_ac_list
+
+
+def resolve_bang_definition(bang_definition, query):
+    url, rank = bang_definition.split(chr(1))
+    if url.startswith('//'):
+        url = 'https:' + url
+    if query:
+        url = url.replace(chr(2), quote_plus(query))
+    else:
+        # go to main instead of search page
+        o = urlparse(url)
+        url = o.scheme + '://' + o.netloc
+
+    rank = int(rank) if len(rank) > 0 else 0
+    return (url, rank)
+
+
+def get_bang_definition_and_autocomplete(bang, external_bangs_db=None):  # pylint: disable=invalid-name
+    if external_bangs_db is None:
+        external_bangs_db = EXTERNAL_BANGS
+
+    bang_definition, bang_ac_list = get_bang_definition_and_ac(external_bangs_db, bang)
+
+    new_autocomplete = []
+    current = [*bang_ac_list]
+    done = set()
+    while len(current) > 0:
+        bang_ac = current.pop(0)
+        done.add(bang_ac)
+
+        current_bang_definition, current_bang_ac_list = get_bang_definition_and_ac(external_bangs_db, bang_ac)
+        if current_bang_definition:
+            _, order = resolve_bang_definition(current_bang_definition, '')
+            new_autocomplete.append((bang_ac, order))
+        for new_bang in current_bang_ac_list:
+            if new_bang not in done and new_bang not in current:
+                current.append(new_bang)
+
+    new_autocomplete.sort(key=lambda t: (-t[1], t[0]))
+    new_autocomplete = list(map(lambda t: t[0], new_autocomplete))
+
+    return bang_definition, new_autocomplete
+
+
+def get_bang_url(search_query, external_bangs_db=None):
+    """
+    Redirects if the user supplied a correct bang search.
+    :param search_query: This is a search_query object which contains preferences and the submitted queries.
+    :return: None if the bang was invalid, else a string of the redirect url.
+    """
+    ret_val = None
+
+    if external_bangs_db is None:
+        external_bangs_db = EXTERNAL_BANGS
+
+    if search_query.external_bang:
+        bang_definition, _ = get_bang_definition_and_ac(external_bangs_db, search_query.external_bang)
+        if bang_definition and isinstance(bang_definition, str):
+            ret_val = resolve_bang_definition(bang_definition, search_query.query)[0]
+
+    return ret_val