conversation API backend update (#360)

### What problem does this PR solve?


Issue link:#345

### Type of change

- [x] New Feature (non-breaking change which adds functionality)

api/db/services/api_service.py

@@ -0,0 +1,66 @@
+#
+#  Copyright 2024 The InfiniFlow Authors. All Rights Reserved.
+#
+#  Licensed under the Apache License, Version 2.0 (the "License");
+#  you may not use this file except in compliance with the License.
+#  You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+#  Unless required by applicable law or agreed to in writing, software
+#  distributed under the License is distributed on an "AS IS" BASIS,
+#  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#  See the License for the specific language governing permissions and
+#  limitations under the License.
+#
+from datetime import datetime
+import peewee
+from api.db.db_models import DB, API4Conversation, APIToken, Dialog
+from api.db.services.common_service import CommonService
+from api.utils import current_timestamp, datetime_format
+
+
+class APITokenService(CommonService):
+    model = APIToken
+
+    @classmethod
+    @DB.connection_context()
+    def used(cls, token):
+        return cls.model.update({
+            "update_time": current_timestamp(),
+            "update_date": datetime_format(datetime.now()),
+        }).where(
+            cls.model.token == token
+        )
+
+
+class API4ConversationService(CommonService):
+    model = API4Conversation
+
+    @classmethod
+    @DB.connection_context()
+    def append_message(cls, id, conversation):
+        cls.model.update_by_id(id, conversation)
+        return cls.model.update(round=cls.model.round + 1).where(id=id).execute()
+
+    @classmethod
+    @DB.connection_context()
+    def stats(cls, tenant_id, from_date, to_date):
+        return cls.model.select(
+            cls.model.create_date.truncate("day").alias("dt"),
+            peewee.fn.COUNT(
+                cls.model.id).alias("pv"),
+            peewee.fn.COUNT(
+                cls.model.user_id.distinct()).alias("uv"),
+            peewee.fn.SUM(
+                cls.model.tokens).alias("tokens"),
+            peewee.fn.SUM(
+                cls.model.duration).alias("duration"),
+            peewee.fn.AVG(
+                cls.model.round).alias("round"),
+            peewee.fn.SUM(
+                cls.model.thumb_up).alias("thumb_up")
+        ).join(Dialog, on=(cls.model.dialog_id == Dialog.id & Dialog.tenant_id == tenant_id)).where(
+            cls.model.create_date >= from_date,
+            cls.model.create_date <= to_date
+        ).group_by(cls.model.create_date.truncate("day")).dicts()