[feat] implement mariadb engine

searx/engines/mariadb_server.py

@@ -0,0 +1,79 @@
+# SPDX-License-Identifier: AGPL-3.0-or-later
+"""MariaDB is a community driven fork of MySQL. Before enabling MariaDB engine,
+you must the install the pip package ``mariadb`` along with the necessary
+prerequities.
+
+`See the following documentation for more details
+<https://mariadb.com/docs/server/connect/programming-languages/c/install/>`_
+
+Example
+=======
+
+This is an example configuration for querying a MariaDB server:
+
+.. code:: yaml
+
+   - name: my_database
+     engine: mariadb_server
+     database: my_database
+     username: searxng
+     password: password
+     limit: 5
+     query_str: 'SELECT * from my_table WHERE my_column=%(query)s'
+
+"""
+
+from typing import TYPE_CHECKING
+
+try:
+    import mariadb
+except ImportError:
+    # import error is ignored because the admin has to install mysql manually to use
+    # the engine
+    pass
+
+if TYPE_CHECKING:
+    import logging
+
+    logger = logging.getLogger()
+
+
+engine_type = 'offline'
+host = "127.0.0.1"
+port = 3306
+database = ""
+username = ""
+password = ""
+query_str = ""
+limit = 10
+paging = True
+result_template = 'key-value.html'
+_connection = None
+
+
+def init(engine_settings):
+    global _connection  # pylint: disable=global-statement
+
+    if 'query_str' not in engine_settings:
+        raise ValueError('query_str cannot be empty')
+
+    if not engine_settings['query_str'].lower().startswith('select '):
+        raise ValueError('only SELECT query is supported')
+
+    _connection = mariadb.connect(database=database, user=username, password=password, host=host, port=port)
+
+
+def search(query, params):
+    query_params = {'query': query}
+    query_to_run = query_str + ' LIMIT {0} OFFSET {1}'.format(limit, (params['pageno'] - 1) * limit)
+    logger.debug("SQL Query: %s", query_to_run)
+
+    with _connection.cursor() as cur:
+        cur.execute(query_to_run, query_params)
+        results = []
+        col_names = [i[0] for i in cur.description]
+        for res in cur:
+            result = dict(zip(col_names, map(str, res)))
+            result['template'] = result_template
+            results.append(result)
+        return results