[mod] split searx.search into different processors

see searx.search.processors.abstract.EngineProcessor

First the method searx call the get_params method.

If the return value is not None, then the searx call the method search.

searx/search/processors/online_currency.py

@@ -0,0 +1,57 @@
+# SPDX-License-Identifier: AGPL-3.0-or-later
+
+import unicodedata
+import re
+
+from searx.data import CURRENCIES
+from .online import OnlineProcessor
+
+
+parser_re = re.compile('.*?(\\d+(?:\\.\\d+)?) ([^.0-9]+) (?:in|to) ([^.0-9]+)', re.I)
+
+
+def normalize_name(name):
+    name = name.lower().replace('-', ' ').rstrip('s')
+    name = re.sub(' +', ' ', name)
+    return unicodedata.normalize('NFKD', name).lower()
+
+
+def name_to_iso4217(name):
+    global CURRENCIES
+    name = normalize_name(name)
+    currency = CURRENCIES['names'].get(name, [name])
+    return currency[0]
+
+
+def iso4217_to_name(iso4217, language):
+    global CURRENCIES
+    return CURRENCIES['iso4217'].get(iso4217, {}).get(language, iso4217)
+
+
+class OnlineCurrencyProcessor(OnlineProcessor):
+
+    engine_type = 'online_currency'
+
+    def get_params(self, search_query, engine_category):
+        params = super().get_params(search_query, engine_category)
+        if params is None:
+            return None
+
+        m = parser_re.match(search_query.query)
+        if not m:
+            return None
+
+        amount_str, from_currency, to_currency = m.groups()
+        try:
+            amount = float(amount_str)
+        except ValueError:
+            return None
+        from_currency = name_to_iso4217(from_currency.strip())
+        to_currency = name_to_iso4217(to_currency.strip())
+
+        params['amount'] = amount
+        params['from'] = from_currency
+        params['to'] = to_currency
+        params['from_name'] = iso4217_to_name(from_currency, 'en')
+        params['to_name'] = iso4217_to_name(to_currency, 'en')
+        return params