zulip-bot-server: Add test suite for zulip bot server.

Fixes: #5358.

api/tests/bot_server_test_lib.py

@@ -0,0 +1,37 @@
+from unittest import TestCase
+import zulip.bot_server
+import json
+from typing import Any, List, Dict, Mapping
+
+class BotServerTestCase(TestCase):
+
+    def setUp(self):
+        # type: () -> None
+        zulip.bot_server.app.testing = True
+        self.app = zulip.bot_server.app.test_client()
+
+    def assert_bot_server_response(self,
+                                   available_bots=None,
+                                   bots_config=None,
+                                   bots_lib_module=None,
+                                   payload_url="/bots/testbot",
+                                   message=dict(message={'key': "test message"}),
+                                   check_success=False,
+                                   ):
+        # type: (List[str], Dict[str, Any], Dict[str, Any], str, Dict[str, Dict[str, Any]], bool) -> None
+
+        if available_bots is not None:
+            zulip.bot_server.available_bots = available_bots
+
+        if bots_config is not None:
+            zulip.bot_server.bots_config = bots_config
+
+        if bots_lib_module is not None:
+            zulip.bot_server.bots_lib_module = bots_lib_module
+
+        response = self.app.post(payload_url, data=json.dumps(message))
+
+        if check_success:
+            assert response.status_code >= 200 and response.status_code < 300
+        else:
+            assert response.status_code >= 400 and response.status_code < 500