[mod] addition of various type hints / engine processors

Continuation of #5147 .. typification of the engine processors.

BTW:

- removed obsolete engine property https_support
- fixed & improved currency_convert
- engine instances can now implement a engine.setup method

[#5147] https://github.com/searxng/searxng/pull/5147

Signed-off-by: Markus Heiser <markus.heiser@darmarit.de>

5 files changed, 56 insertions, 29 deletions

diff --git a/searx/engines/__init__.py b/searx/engines/__init__.py
index b1e24aea2..30ef7fd75 100644
--- a/searx/engines/__init__.py
+++ b/searx/engines/__init__.py
@@ -51,7 +51,10 @@ ENGINE_DEFAULT_ARGS: dict[str, int | str | list[t.Any] | dict[str, t.Any] | bool
 DEFAULT_CATEGORY = 'other'
 
 categories: "dict[str, list[Engine|types.ModuleType]]" = {'general': []}
+
 engines: "dict[str, Engine | types.ModuleType]" = {}
+"""Global registered engine instances."""
+
 engine_shortcuts = {}
 """Simple map of registered *shortcuts* to name of the engine (or ``None``).
 
@@ -144,6 +147,9 @@ def load_engine(engine_data: dict[str, t.Any]) -> "Engine | types.ModuleType | N
 
     set_loggers(engine, engine_name)
 
+    if not call_engine_setup(engine, engine_data):
+        return None
+
     if not any(cat in settings['categories_as_tabs'] for cat in engine.categories):
         engine.categories.append(DEFAULT_CATEGORY)
 
@@ -223,6 +229,25 @@ def is_engine_active(engine: "Engine | types.ModuleType"):
     return True
 
 
+def call_engine_setup(engine: "Engine | types.ModuleType", engine_data: dict[str, t.Any]) -> bool:
+    setup_ok = False
+    setup_func = getattr(engine, "setup", None)
+
+    if setup_func is None:
+        setup_ok = True
+    elif not callable(setup_func):
+        logger.error("engine's setup method isn't a callable (is of type: %s)", type(setup_func))
+    else:
+        try:
+            setup_ok = engine.setup(engine_data)
+        except Exception as e:  # pylint: disable=broad-except
+            logger.exception('exception : {0}'.format(e))
+
+    if not setup_ok:
+        logger.error("%s: Engine setup was not successful, engine is set to inactive.", engine.name)
+    return setup_ok
+
+
 def register_engine(engine: "Engine | types.ModuleType"):
     if engine.name in engines:
         logger.error('Engine config error: ambiguous name: {0}'.format(engine.name))
diff --git a/searx/engines/currency_convert.py b/searx/engines/currency_convert.py
index c4c757e3f..0b9b339a9 100644
--- a/searx/engines/currency_convert.py
+++ b/searx/engines/currency_convert.py
@@ -1,53 +1,58 @@
 # SPDX-License-Identifier: AGPL-3.0-or-later
-"""Currency convert (DuckDuckGo)
-"""
+"""Currency convert (DuckDuckGo)"""
 
+import typing as t
 import json
 from searx.result_types import EngineResults
 
+if t.TYPE_CHECKING:
+    from searx.search.processors import OnlineCurrenciesParams
+    from searx.extended_types import SXNG_Response
+
 # about
 about = {
-    "website": 'https://duckduckgo.com/',
-    "wikidata_id": 'Q12805',
-    "official_api_documentation": 'https://duckduckgo.com/api',
+    "website": "https://duckduckgo.com/",
+    "wikidata_id": "Q12805",
+    "official_api_documentation": "https://duckduckgo.com/api",
     "use_official_api": False,
     "require_api_key": False,
-    "results": 'JSONP',
+    "results": "JSONP",
     "description": "Service from DuckDuckGo.",
 }
 
-engine_type = 'online_currency'
-categories = []
-base_url = 'https://duckduckgo.com/js/spice/currency/1/{0}/{1}'
-weight = 100
+engine_type = "online_currency"
+categories = ["currency", "general"]
+
+base_url = "https://duckduckgo.com/js/spice/currency/1/%(from_iso4217)s/%(to_iso4217)s"
+ddg_link_url = "https://duckduckgo.com/?q=%(from_iso4217)s+to+%(to_iso4217)s"
 
-https_support = True
+weight = 100
 
 
-def request(_query, params):
-    params['url'] = base_url.format(params['from'], params['to'])
-    return params
+def request(query: str, params: "OnlineCurrenciesParams") -> None:  # pylint: disable=unused-argument
+    params["url"] = base_url % params
 
 
-def response(resp) -> EngineResults:
+def response(resp: "SXNG_Response") -> EngineResults:
     res = EngineResults()
 
     # remove first and last lines to get only json
-    json_resp = resp.text[resp.text.find('\n') + 1 : resp.text.rfind('\n') - 2]
+    json_resp = resp.text[resp.text.find("\n") + 1 : resp.text.rfind("\n") - 2]
     try:
         conversion_rate = float(json.loads(json_resp)["to"][0]["mid"])
     except IndexError:
         return res
-    answer = '{0} {1} = {2} {3}, 1 {1} ({5}) = {4} {3} ({6})'.format(
-        resp.search_params['amount'],
-        resp.search_params['from'],
-        resp.search_params['amount'] * conversion_rate,
-        resp.search_params['to'],
+
+    params: OnlineCurrenciesParams = resp.search_params  # pyright: ignore[reportAssignmentType]
+    answer = "{0} {1} = {2} {3} (1 {5} : {4} {6})".format(
+        params["amount"],
+        params["from_iso4217"],
+        params["amount"] * conversion_rate,
+        params["to_iso4217"],
         conversion_rate,
-        resp.search_params['from_name'],
-        resp.search_params['to_name'],
+        params["from_name"],
+        params["to_name"],
     )
-
-    url = f"https://duckduckgo.com/?q={resp.search_params['from']}+to+{resp.search_params['to']}"
+    url = ddg_link_url % params
     res.add(res.types.Answer(answer=answer, url=url))
     return res
diff --git a/searx/engines/dictzone.py b/searx/engines/dictzone.py
index bda056edd..d393eae92 100644
--- a/searx/engines/dictzone.py
+++ b/searx/engines/dictzone.py
@@ -24,7 +24,6 @@ engine_type = 'online_dictionary'
 categories = ['general', 'translate']
 base_url = "https://dictzone.com"
 weight = 100
-https_support = True
 
 
 def request(query, params):  # pylint: disable=unused-argument
diff --git a/searx/engines/metacpan.py b/searx/engines/metacpan.py
index 50608bc11..32bc55b89 100644
--- a/searx/engines/metacpan.py
+++ b/searx/engines/metacpan.py
@@ -3,7 +3,6 @@
 """
 
 from urllib.parse import urlunparse
-from json import dumps
 
 # about
 about = {
@@ -56,7 +55,7 @@ def request(query, params):
     query_data = query_data_template
     query_data["query"]["multi_match"]["query"] = query
     query_data["from"] = (params["pageno"] - 1) * number_of_results
-    params["data"] = dumps(query_data)
+    params["json"] = query_data
     return params
 
 
diff --git a/searx/engines/translated.py b/searx/engines/translated.py
index cffb6eda3..08808cfd2 100644
--- a/searx/engines/translated.py
+++ b/searx/engines/translated.py
@@ -22,7 +22,6 @@ categories = ['general', 'translate']
 api_url = "https://api.mymemory.translated.net"
 web_url = "https://mymemory.translated.net"
 weight = 100
-https_support = True
 
 api_key = ''