perf: reduce memory usage by ~200MB+ at startup (#2013)

* perf: reduce memory usage by ~200MB+ at startup

Two key optimizations:

1. Use importlib.util.find_spec() instead of __import__() in dependency
   checking. find_spec() only locates modules without executing them,
   avoiding loading all 36 dependencies (~222MB) into memory at startup.

2. Introduce shared aiohttp.ClientSession via httpclient module.
   Previously, every HTTP request created a new ClientSession, which
   creates a new TCPConnector and SSL context, loading system root
   certificates each time (~270MB total allocations observed via memray).
   Now all HTTP client code reuses shared sessions.

   - satori.py and coze_server_api/client.py are left unchanged as they
     create one session per adapter lifecycle (not per-request).

Profiling data (memray):
- Peak memory: 403MB
- SSL context creation: 270MB / 6.7M allocations (67% of total)
- Dependency import: 222MB (55% of peak)
- Expected reduction: 150-350MB at startup

* fix: remove unused aiohttp imports (ruff F401)

* style: ruff format

src/langbot/libs/wechatpad_api/util/http_util.py

@@ -1,5 +1,5 @@
 import requests
-import aiohttp
+from langbot.pkg.utils import httpclient
 
 
 def post_json(base_url, token, data=None):
@@ -63,16 +63,16 @@ async def async_request(
     """
     headers = {'Content-Type': 'application/json'}
     url = f'{base_url}?key={token_key}'
-    async with aiohttp.ClientSession() as session:
-        async with session.request(
-            method=method, url=url, params=params, headers=headers, data=data, json=json
-        ) as response:
-            response.raise_for_status()  # 如果状态码不是200，抛出异常
-            result = await response.json()
-            # print(result)
-            return result
-            # if result.get('Code') == 200:
-            #
-            #     return await result
-            # else:
-            #     raise RuntimeError("请求失败",response.text)
+    session = httpclient.get_session()
+    async with session.request(
+        method=method, url=url, params=params, headers=headers, data=data, json=json
+    ) as response:
+        response.raise_for_status()  # 如果状态码不是200，抛出异常
+        result = await response.json()
+        # print(result)
+        return result
+        # if result.get('Code') == 200:
+        #
+        #     return await result
+        # else:
+        #     raise RuntimeError("请求失败",response.text)

src/langbot/pkg/api/http/service/space.py

@@ -1,6 +1,6 @@
 from __future__ import annotations
 
-import aiohttp
+from langbot.pkg.utils import httpclient
 import typing
 import datetime
 import time
@@ -99,49 +99,49 @@ class SpaceService:
         space_config = self._get_space_config()
         space_url = space_config['url']
 
-        async with aiohttp.ClientSession() as session:
-            async with session.post(
-                f'{space_url}/api/v1/accounts/oauth/token',
-                json={'code': code, 'instance_id': constants.instance_id},
-            ) as response:
-                if response.status != 200:
-                    raise ValueError(f'Failed to exchange OAuth code: {await response.text()}')
-                data = await response.json()
-                if data.get('code') != 0:
-                    raise ValueError(f'Failed to exchange OAuth code: {data.get("msg")}')
-                return data.get('data', {})
+        session = httpclient.get_session()
+        async with session.post(
+            f'{space_url}/api/v1/accounts/oauth/token',
+            json={'code': code, 'instance_id': constants.instance_id},
+        ) as response:
+            if response.status != 200:
+                raise ValueError(f'Failed to exchange OAuth code: {await response.text()}')
+            data = await response.json()
+            if data.get('code') != 0:
+                raise ValueError(f'Failed to exchange OAuth code: {data.get("msg")}')
+            return data.get('data', {})
 
     async def refresh_token(self, refresh_token: str) -> typing.Dict:
         """Refresh Space access token"""
         space_config = self._get_space_config()
         space_url = space_config['url']
 
-        async with aiohttp.ClientSession() as session:
-            async with session.post(
-                f'{space_url}/api/v1/accounts/token/refresh', json={'refresh_token': refresh_token}
-            ) as response:
-                if response.status != 200:
-                    raise ValueError(f'Failed to refresh token: {await response.text()}')
-                data = await response.json()
-                if data.get('code') != 0:
-                    raise ValueError(f'Failed to refresh token: {data.get("msg")}')
-                return data.get('data', {})
+        session = httpclient.get_session()
+        async with session.post(
+            f'{space_url}/api/v1/accounts/token/refresh', json={'refresh_token': refresh_token}
+        ) as response:
+            if response.status != 200:
+                raise ValueError(f'Failed to refresh token: {await response.text()}')
+            data = await response.json()
+            if data.get('code') != 0:
+                raise ValueError(f'Failed to refresh token: {data.get("msg")}')
+            return data.get('data', {})
 
     async def get_user_info_raw(self, access_token: str) -> typing.Dict:
         """Get user info from Space using access token (no validation)"""
         space_config = self._get_space_config()
         space_url = space_config['url']
 
-        async with aiohttp.ClientSession() as session:
-            async with session.get(
-                f'{space_url}/api/v1/accounts/me', headers={'Authorization': f'Bearer {access_token}'}
-            ) as response:
-                if response.status != 200:
-                    raise ValueError(f'Failed to get user info: {await response.text()}')
-                data = await response.json()
-                if data.get('code') != 0:
-                    raise ValueError(f'Failed to get user info: {data.get("msg")}')
-                return data.get('data', {})
+        session = httpclient.get_session()
+        async with session.get(
+            f'{space_url}/api/v1/accounts/me', headers={'Authorization': f'Bearer {access_token}'}
+        ) as response:
+            if response.status != 200:
+                raise ValueError(f'Failed to get user info: {await response.text()}')
+            data = await response.json()
+            if data.get('code') != 0:
+                raise ValueError(f'Failed to get user info: {data.get("msg")}')
+            return data.get('data', {})
 
     # === API calls with token validation ===
 
@@ -178,12 +178,12 @@ class SpaceService:
         space_config = self._get_space_config()
         space_url = space_config['url']
 
-        async with aiohttp.ClientSession() as session:
-            async with session.get(f'{space_url}/api/v1/models') as response:
-                if response.status != 200:
-                    raise ValueError(f'Failed to get models: {await response.text()}')
-                data = await response.json()
-                if data.get('code') != 0:
-                    raise ValueError(f'Failed to get models: {data.get("msg")}')
-                models_data = data.get('data', {}).get('models', [])
-                return [SpaceModel.model_validate(model_dict) for model_dict in models_data]
+        session = httpclient.get_session()
+        async with session.get(f'{space_url}/api/v1/models') as response:
+            if response.status != 200:
+                raise ValueError(f'Failed to get models: {await response.text()}')
+            data = await response.json()
+            if data.get('code') != 0:
+                raise ValueError(f'Failed to get models: {data.get("msg")}')
+            models_data = data.get('data', {}).get('models', [])
+            return [SpaceModel.model_validate(model_dict) for model_dict in models_data]

src/langbot/pkg/core/bootutils/deps.py

@@ -1,3 +1,4 @@
+import importlib.util
 import pip
 import os
 from ...utils import pkgmgr
@@ -49,9 +50,10 @@ async def check_deps() -> list[str]:
 
     missing_deps = []
     for dep in required_deps:
-        try:
-            __import__(dep)
-        except ImportError:
+        # Use find_spec instead of __import__ to avoid actually loading
+        # all modules into memory. find_spec only checks if the module
+        # can be found, without executing module-level code.
+        if importlib.util.find_spec(dep) is None:
             missing_deps.append(dep)
     return missing_deps
 

src/langbot/pkg/pipeline/cntfilter/filters/baiduexamine.py

@@ -1,10 +1,9 @@
 from __future__ import annotations
 
-import aiohttp
-
 from .. import entities
 from .. import filter as filter_model
 import langbot_plugin.api.entities.builtin.pipeline.query as pipeline_query
+from langbot.pkg.utils import httpclient
 
 BAIDU_EXAMINE_URL = 'https://aip.baidubce.com/rest/2.0/solution/v1/text_censor/v2/user_defined?access_token={}'
 BAIDU_EXAMINE_TOKEN_URL = 'https://aip.baidubce.com/oauth/2.0/token'
@@ -15,50 +14,50 @@ class BaiduCloudExamine(filter_model.ContentFilter):
     """百度云内容审核"""
 
     async def _get_token(self) -> str:
-        async with aiohttp.ClientSession() as session:
-            async with session.post(
-                BAIDU_EXAMINE_TOKEN_URL,
-                params={
-                    'grant_type': 'client_credentials',
-                    'client_id': self.ap.pipeline_cfg.data['baidu-cloud-examine']['api-key'],
-                    'client_secret': self.ap.pipeline_cfg.data['baidu-cloud-examine']['api-secret'],
-                },
-            ) as resp:
-                return (await resp.json())['access_token']
+        session = httpclient.get_session()
+        async with session.post(
+            BAIDU_EXAMINE_TOKEN_URL,
+            params={
+                'grant_type': 'client_credentials',
+                'client_id': self.ap.pipeline_cfg.data['baidu-cloud-examine']['api-key'],
+                'client_secret': self.ap.pipeline_cfg.data['baidu-cloud-examine']['api-secret'],
+            },
+        ) as resp:
+            return (await resp.json())['access_token']
 
     async def process(self, query: pipeline_query.Query, message: str) -> entities.FilterResult:
-        async with aiohttp.ClientSession() as session:
-            async with session.post(
-                BAIDU_EXAMINE_URL.format(await self._get_token()),
-                headers={
-                    'Content-Type': 'application/x-www-form-urlencoded',
-                    'Accept': 'application/json',
-                },
-                data=f'text={message}'.encode('utf-8'),
-            ) as resp:
-                result = await resp.json()
+        session = httpclient.get_session()
+        async with session.post(
+            BAIDU_EXAMINE_URL.format(await self._get_token()),
+            headers={
+                'Content-Type': 'application/x-www-form-urlencoded',
+                'Accept': 'application/json',
+            },
+            data=f'text={message}'.encode('utf-8'),
+        ) as resp:
+            result = await resp.json()
 
-                if 'error_code' in result:
+            if 'error_code' in result:
+                return entities.FilterResult(
+                    level=entities.ResultLevel.BLOCK,
+                    replacement=message,
+                    user_notice='',
+                    console_notice=f'百度云判定出错，错误信息：{result["error_msg"]}',
+                )
+            else:
+                conclusion = result['conclusion']
+
+                if conclusion in ('合规'):
+                    return entities.FilterResult(
+                        level=entities.ResultLevel.PASS,
+                        replacement=message,
+                        user_notice='',
+                        console_notice=f'百度云判定结果：{conclusion}',
+                    )
+                else:
                     return entities.FilterResult(
                         level=entities.ResultLevel.BLOCK,
                         replacement=message,
-                        user_notice='',
-                        console_notice=f'百度云判定出错，错误信息：{result["error_msg"]}',
+                        user_notice='消息中存在不合适的内容, 请修改',
+                        console_notice=f'百度云判定结果：{conclusion}',
                     )
-                else:
-                    conclusion = result['conclusion']
-
-                    if conclusion in ('合规'):
-                        return entities.FilterResult(
-                            level=entities.ResultLevel.PASS,
-                            replacement=message,
-                            user_notice='',
-                            console_notice=f'百度云判定结果：{conclusion}',
-                        )
-                    else:
-                        return entities.FilterResult(
-                            level=entities.ResultLevel.BLOCK,
-                            replacement=message,
-                            user_notice='消息中存在不合适的内容, 请修改',
-                            console_notice=f'百度云判定结果：{conclusion}',
-                        )

src/langbot/pkg/platform/sources/discord.py

@@ -14,7 +14,7 @@ import io
 import asyncio
 from enum import Enum
 
-import aiohttp
+from langbot.pkg.utils import httpclient
 import pydantic
 
 import langbot_plugin.api.definition.abstract.platform.adapter as abstract_platform_adapter
@@ -622,23 +622,23 @@ class DiscordMessageConverter(abstract_platform_adapter.AbstractMessageConverter
                     image_bytes = base64.b64decode(base64_data)
                 elif ele.url:
                     # 从URL下载图片
-                    async with aiohttp.ClientSession() as session:
-                        async with session.get(ele.url) as response:
-                            image_bytes = await response.read()
-                            # 从URL或Content-Type推断文件类型
-                            content_type = response.headers.get('Content-Type', '')
-                            if 'jpeg' in content_type or 'jpg' in content_type:
-                                filename = f'{uuid.uuid4()}.jpg'
-                            elif 'gif' in content_type:
-                                filename = f'{uuid.uuid4()}.gif'
-                            elif 'webp' in content_type:
-                                filename = f'{uuid.uuid4()}.webp'
-                            elif ele.url.lower().endswith(('.jpg', '.jpeg')):
-                                filename = f'{uuid.uuid4()}.jpg'
-                            elif ele.url.lower().endswith('.gif'):
-                                filename = f'{uuid.uuid4()}.gif'
-                            elif ele.url.lower().endswith('.webp'):
-                                filename = f'{uuid.uuid4()}.webp'
+                    session = httpclient.get_session()
+                    async with session.get(ele.url) as response:
+                        image_bytes = await response.read()
+                        # 从URL或Content-Type推断文件类型
+                        content_type = response.headers.get('Content-Type', '')
+                        if 'jpeg' in content_type or 'jpg' in content_type:
+                            filename = f'{uuid.uuid4()}.jpg'
+                        elif 'gif' in content_type:
+                            filename = f'{uuid.uuid4()}.gif'
+                        elif 'webp' in content_type:
+                            filename = f'{uuid.uuid4()}.webp'
+                        elif ele.url.lower().endswith(('.jpg', '.jpeg')):
+                            filename = f'{uuid.uuid4()}.jpg'
+                        elif ele.url.lower().endswith('.gif'):
+                            filename = f'{uuid.uuid4()}.gif'
+                        elif ele.url.lower().endswith('.webp'):
+                            filename = f'{uuid.uuid4()}.webp'
                 elif ele.path:
                     # 从文件路径读取图片
                     # 确保路径没有空字节
@@ -702,9 +702,9 @@ class DiscordMessageConverter(abstract_platform_adapter.AbstractMessageConverter
                     file_base64 = ele.base64.split(',')[-1]
                     file_bytes = base64.b64decode(file_base64)
                 elif ele.url:
-                    async with aiohttp.ClientSession() as session:
-                        async with session.get(ele.url) as response:
-                            file_bytes = await response.read()
+                    session = httpclient.get_session()
+                    async with session.get(ele.url) as response:
+                        file_bytes = await response.read()
                 if file_bytes:
                     files.append(discord.File(fp=io.BytesIO(file_bytes), filename=filename))
             elif isinstance(ele, platform_message.File):
@@ -717,9 +717,9 @@ class DiscordMessageConverter(abstract_platform_adapter.AbstractMessageConverter
                     else:
                         file_bytes = base64.b64decode(ele.base64)
                 elif ele.url:
-                    async with aiohttp.ClientSession() as session:
-                        async with session.get(ele.url) as response:
-                            file_bytes = await response.read()
+                    session = httpclient.get_session()
+                    async with session.get(ele.url) as response:
+                        file_bytes = await response.read()
                 if file_bytes:
                     files.append(discord.File(fp=io.BytesIO(file_bytes), filename=filename))
             elif isinstance(ele, platform_message.Forward):
@@ -775,12 +775,12 @@ class DiscordMessageConverter(abstract_platform_adapter.AbstractMessageConverter
 
         # attachments
         for attachment in message.attachments:
-            async with aiohttp.ClientSession(trust_env=True) as session:
-                async with session.get(attachment.url) as response:
-                    image_data = await response.read()
-                    image_base64 = base64.b64encode(image_data).decode('utf-8')
-                    image_format = response.headers['Content-Type']
-                    element_list.append(platform_message.Image(base64=f'data:{image_format};base64,{image_base64}'))
+            session = httpclient.get_session(trust_env=True)
+            async with session.get(attachment.url) as response:
+                image_data = await response.read()
+                image_base64 = base64.b64encode(image_data).decode('utf-8')
+                image_format = response.headers['Content-Type']
+                element_list.append(platform_message.Image(base64=f'data:{image_format};base64,{image_base64}'))
 
         return platform_message.MessageChain(element_list)
 

src/langbot/pkg/platform/sources/kook.py

@@ -9,6 +9,8 @@ import traceback
 import time
 
 import aiohttp
+
+from langbot.pkg.utils import httpclient
 import websockets
 import pydantic
 
@@ -120,16 +122,16 @@ class KookMessageConverter(abstract_platform_adapter.AbstractMessageConverter):
             if content:
                 # Download image and convert to base64
                 try:
-                    async with aiohttp.ClientSession() as session:
-                        async with session.get(content) as response:
-                            if response.status == 200:
-                                image_bytes = await response.read()
-                                image_base64 = base64.b64encode(image_bytes).decode('utf-8')
-                                # Detect image format
-                                content_type = response.headers.get('Content-Type', 'image/png')
-                                components.append(
-                                    platform_message.Image(base64=f'data:{content_type};base64,{image_base64}')
-                                )
+                    session = httpclient.get_session()
+                    async with session.get(content) as response:
+                        if response.status == 200:
+                            image_bytes = await response.read()
+                            image_base64 = base64.b64encode(image_bytes).decode('utf-8')
+                            # Detect image format
+                            content_type = response.headers.get('Content-Type', 'image/png')
+                            components.append(
+                                platform_message.Image(base64=f'data:{content_type};base64,{image_base64}')
+                            )
                 except Exception:
                     # If download fails, just add as plain text
                     components.append(platform_message.Plain(text=f'[Image: {content}]'))
@@ -295,17 +297,17 @@ class KookAdapter(abstract_platform_adapter.AbstractMessagePlatformAdapter):
             'Authorization': f'Bot {self.config["token"]}',
         }
 
-        async with aiohttp.ClientSession() as session:
-            async with session.get(base_url, params=params, headers=headers) as response:
-                if response.status == 200:
-                    data = await response.json()
-                    if data.get('code') == 0:
-                        gateway_url = data['data']['url']
-                        return gateway_url
-                    else:
-                        raise Exception(f'Failed to get gateway URL: {data.get("message")}')
+        session = httpclient.get_session()
+        async with session.get(base_url, params=params, headers=headers) as response:
+            if response.status == 200:
+                data = await response.json()
+                if data.get('code') == 0:
+                    gateway_url = data['data']['url']
+                    return gateway_url
                 else:
-                    raise Exception(f'Failed to get gateway URL: HTTP {response.status}')
+                    raise Exception(f'Failed to get gateway URL: {data.get("message")}')
+            else:
+                raise Exception(f'Failed to get gateway URL: HTTP {response.status}')
 
     async def _get_bot_user_info(self) -> dict:
         """Get bot's own user information from KOOK API"""
@@ -315,17 +317,17 @@ class KookAdapter(abstract_platform_adapter.AbstractMessagePlatformAdapter):
             'Authorization': f'Bot {self.config["token"]}',
         }
 
-        async with aiohttp.ClientSession() as session:
-            async with session.get(base_url, headers=headers) as response:
-                if response.status == 200:
-                    data = await response.json()
-                    if data.get('code') == 0:
-                        user_info = data['data']
-                        return user_info
-                    else:
-                        raise Exception(f'Failed to get bot user info: {data.get("message")}')
+        session = httpclient.get_session()
+        async with session.get(base_url, headers=headers) as response:
+            if response.status == 200:
+                data = await response.json()
+                if data.get('code') == 0:
+                    user_info = data['data']
+                    return user_info
                 else:
-                    raise Exception(f'Failed to get bot user info: HTTP {response.status}')
+                    raise Exception(f'Failed to get bot user info: {data.get("message")}')
+            else:
+                raise Exception(f'Failed to get bot user info: HTTP {response.status}')
 
     async def _handle_hello(self, data: dict):
         """Handle HELLO signal (signal 1)"""
@@ -510,7 +512,7 @@ class KookAdapter(abstract_platform_adapter.AbstractMessagePlatformAdapter):
 
         try:
             if not self.http_session:
-                self.http_session = aiohttp.ClientSession()
+                self.http_session = httpclient.get_session()
 
             async with self.http_session.post(url, json=payload, headers=headers) as response:
                 if response.status == 200:
@@ -576,7 +578,7 @@ class KookAdapter(abstract_platform_adapter.AbstractMessagePlatformAdapter):
 
         try:
             if not self.http_session:
-                self.http_session = aiohttp.ClientSession()
+                self.http_session = httpclient.get_session()
 
             async with self.http_session.post(url, json=payload, headers=headers) as response:
                 if response.status == 200:
@@ -624,7 +626,7 @@ class KookAdapter(abstract_platform_adapter.AbstractMessagePlatformAdapter):
 
         try:
             # Create HTTP session
-            self.http_session = aiohttp.ClientSession()
+            self.http_session = httpclient.get_session()
 
             await self.logger.info('Starting KOOK adapter')
 

src/langbot/pkg/platform/sources/lark.py

@@ -17,7 +17,7 @@ import tempfile
 import os
 import mimetypes
 
-import aiohttp
+from langbot.pkg.utils import httpclient
 import lark_oapi.ws.exception
 import quart
 from lark_oapi.api.im.v1 import *
@@ -78,13 +78,13 @@ class LarkMessageConverter(abstract_platform_adapter.AbstractMessageConverter):
                 return None
         elif msg.url:
             try:
-                async with aiohttp.ClientSession() as session:
-                    async with session.get(msg.url) as response:
-                        if response.status == 200:
-                            image_bytes = await response.read()
-                        else:
-                            print(f'Failed to download image from {msg.url}: HTTP {response.status}')
-                            return None
+                session = httpclient.get_session()
+                async with session.get(msg.url) as response:
+                    if response.status == 200:
+                        image_bytes = await response.read()
+                    else:
+                        print(f'Failed to download image from {msg.url}: HTTP {response.status}')
+                        return None
             except Exception as e:
                 print(f'Failed to download image from {msg.url}: {e}')
                 traceback.print_exc()
@@ -208,10 +208,10 @@ class LarkMessageConverter(abstract_platform_adapter.AbstractMessageConverter):
                 pass
         elif msg.url:
             try:
-                async with aiohttp.ClientSession() as session:
-                    async with session.get(msg.url) as resp:
-                        if resp.status == 200:
-                            data = await resp.read()
+                session = httpclient.get_session()
+                async with session.get(msg.url) as resp:
+                    if resp.status == 200:
+                        data = await resp.read()
             except Exception:
                 pass
         elif msg.path:

src/langbot/pkg/platform/sources/legacy/gewechat.py

@@ -9,7 +9,7 @@ import copy
 import threading
 
 import quart
-import aiohttp
+from langbot.pkg.utils import httpclient
 
 import langbot_plugin.api.definition.abstract.platform.adapter as abstract_platform_adapter
 from ....core import app
@@ -639,14 +639,14 @@ class GeWeChatAdapter(abstract_platform_adapter.AbstractMessagePlatformAdapter):
 
     async def run_async(self):
         if not self.config['token']:
-            async with aiohttp.ClientSession() as session:
-                async with session.post(
-                    f'{self.config["gewechat_url"]}/v2/api/tools/getTokenId',
-                    json={'app_id': self.config['app_id']},
-                ) as response:
-                    if response.status != 200:
-                        raise Exception(f'获取gewechat token失败: {await response.text()}')
-                    self.config['token'] = (await response.json())['data']
+            session = httpclient.get_session()
+            async with session.post(
+                f'{self.config["gewechat_url"]}/v2/api/tools/getTokenId',
+                json={'app_id': self.config['app_id']},
+            ) as response:
+                if response.status != 200:
+                    raise Exception(f'获取gewechat token失败: {await response.text()}')
+                self.config['token'] = (await response.json())['data']
 
         self.bot = gewechat_client.GewechatClient(f'{self.config["gewechat_url"]}/v2/api', self.config['token'])
 

src/langbot/pkg/platform/sources/telegram.py

@@ -9,9 +9,9 @@ import telegramify_markdown
 import typing
 import traceback
 import base64
-import aiohttp
 import pydantic
 
+from langbot.pkg.utils import httpclient
 import langbot_plugin.api.definition.abstract.platform.adapter as abstract_platform_adapter
 import langbot_plugin.api.entities.builtin.platform.message as platform_message
 import langbot_plugin.api.entities.builtin.platform.events as platform_events
@@ -33,9 +33,9 @@ class TelegramMessageConverter(abstract_platform_adapter.AbstractMessageConverte
                 if component.base64:
                     photo_bytes = base64.b64decode(component.base64)
                 elif component.url:
-                    async with aiohttp.ClientSession() as session:
-                        async with session.get(component.url) as response:
-                            photo_bytes = await response.read()
+                    session = httpclient.get_session()
+                    async with session.get(component.url) as response:
+                        photo_bytes = await response.read()
                 elif component.path:
                     with open(component.path, 'rb') as f:
                         photo_bytes = f.read()
@@ -74,10 +74,9 @@ class TelegramMessageConverter(abstract_platform_adapter.AbstractMessageConverte
             file_bytes = None
             file_format = ''
 
-            async with aiohttp.ClientSession(trust_env=True) as session:
-                async with session.get(file.file_path) as response:
-                    file_bytes = await response.read()
-                    file_format = 'image/jpeg'
+            async with httpclient.get_session(trust_env=True).get(file.file_path) as response:
+                file_bytes = await response.read()
+                file_format = 'image/jpeg'
 
             message_components.append(
                 platform_message.Image(
@@ -94,9 +93,8 @@ class TelegramMessageConverter(abstract_platform_adapter.AbstractMessageConverte
             file_bytes = None
             file_format = message.voice.mime_type or 'audio/ogg'
 
-            async with aiohttp.ClientSession(trust_env=True) as session:
-                async with session.get(file.file_path) as response:
-                    file_bytes = await response.read()
+            async with httpclient.get_session(trust_env=True).get(file.file_path) as response:
+                file_bytes = await response.read()
 
             message_components.append(
                 platform_message.Voice(

src/langbot/pkg/platform/webhook_pusher.py

@@ -3,6 +3,8 @@ from __future__ import annotations
 import asyncio
 import logging
 import aiohttp
+
+from langbot.pkg.utils import httpclient
 import uuid
 from typing import TYPE_CHECKING
 
@@ -119,23 +121,23 @@ class WebhookPusher:
             dict | None: The response JSON if successful, None otherwise
         """
         try:
-            async with aiohttp.ClientSession() as session:
-                async with session.post(
-                    url,
-                    json=payload,
-                    headers={'Content-Type': 'application/json'},
-                    timeout=aiohttp.ClientTimeout(total=15),
-                ) as response:
-                    if response.status >= 400:
-                        self.logger.warning(f'Webhook {url} returned status {response.status}')
+            session = httpclient.get_session()
+            async with session.post(
+                url,
+                json=payload,
+                headers={'Content-Type': 'application/json'},
+                timeout=aiohttp.ClientTimeout(total=15),
+            ) as response:
+                if response.status >= 400:
+                    self.logger.warning(f'Webhook {url} returned status {response.status}')
+                    return None
+                else:
+                    self.logger.debug(f'Successfully pushed to webhook {url}')
+                    try:
+                        return await response.json()
+                    except Exception as json_error:
+                        self.logger.debug(f'Failed to parse JSON response from webhook {url}: {json_error}')
                         return None
-                    else:
-                        self.logger.debug(f'Successfully pushed to webhook {url}')
-                        try:
-                            return await response.json()
-                        except Exception as json_error:
-                            self.logger.debug(f'Failed to parse JSON response from webhook {url}: {json_error}')
-                            return None
         except asyncio.TimeoutError:
             self.logger.warning(f'Timeout pushing to webhook {url}')
             return None

src/langbot/pkg/provider/runners/n8nsvapi.py

@@ -5,6 +5,8 @@ import json
 import uuid
 import aiohttp
 
+from langbot.pkg.utils import httpclient
+
 from .. import runner
 from ...core import app
 import langbot_plugin.api.entities.builtin.pipeline.query as pipeline_query
@@ -217,50 +219,50 @@ class N8nServiceAPIRunner(runner.RequestRunner):
                 self.ap.logger.debug('no auth')
 
             # 调用webhook
-            async with aiohttp.ClientSession() as session:
-                if is_stream:
-                    # 流式请求
-                    async with session.post(
-                        self.webhook_url, json=payload, headers=headers, auth=auth, timeout=self.timeout
-                    ) as response:
+            session = httpclient.get_session()
+            if is_stream:
+                # 流式请求
+                async with session.post(
+                    self.webhook_url, json=payload, headers=headers, auth=auth, timeout=self.timeout
+                ) as response:
+                    if response.status != 200:
+                        error_text = await response.text()
+                        self.ap.logger.error(f'n8n webhook call failed: {response.status}, {error_text}')
+                        raise Exception(f'n8n webhook call failed: {response.status}, {error_text}')
+
+                    # 处理流式响应
+                    async for chunk in self._process_stream_response(response):
+                        yield chunk
+            else:
+                async with session.post(
+                    self.webhook_url, json=payload, headers=headers, auth=auth, timeout=self.timeout
+                ) as response:
+                    try:
+                        async for chunk in self._process_stream_response(response):
+                            output_content = chunk.content if chunk.is_final else ''
+                    except:
+                        # 非流式请求（保持原有逻辑）
                         if response.status != 200:
                             error_text = await response.text()
                             self.ap.logger.error(f'n8n webhook call failed: {response.status}, {error_text}')
                             raise Exception(f'n8n webhook call failed: {response.status}, {error_text}')
 
-                        # 处理流式响应
-                        async for chunk in self._process_stream_response(response):
-                            yield chunk
-                else:
-                    async with session.post(
-                        self.webhook_url, json=payload, headers=headers, auth=auth, timeout=self.timeout
-                    ) as response:
-                        try:
-                            async for chunk in self._process_stream_response(response):
-                                output_content = chunk.content if chunk.is_final else ''
-                        except:
-                            # 非流式请求（保持原有逻辑）
-                            if response.status != 200:
-                                error_text = await response.text()
-                                self.ap.logger.error(f'n8n webhook call failed: {response.status}, {error_text}')
-                                raise Exception(f'n8n webhook call failed: {response.status}, {error_text}')
+                        # 解析响应
+                        response_data = await response.json()
+                        self.ap.logger.debug(f'n8n webhook response: {response_data}')
 
-                            # 解析响应
-                            response_data = await response.json()
-                            self.ap.logger.debug(f'n8n webhook response: {response_data}')
+                        # 从响应中提取输出
+                        if self.output_key in response_data:
+                            output_content = response_data[self.output_key]
+                        else:
+                            # 如果没有指定的输出键，则使用整个响应
+                            output_content = json.dumps(response_data, ensure_ascii=False)
 
-                            # 从响应中提取输出
-                            if self.output_key in response_data:
-                                output_content = response_data[self.output_key]
-                            else:
-                                # 如果没有指定的输出键，则使用整个响应
-                                output_content = json.dumps(response_data, ensure_ascii=False)
-
-                        # 返回消息
-                        yield provider_message.Message(
-                            role='assistant',
-                            content=output_content,
-                        )
+                    # 返回消息
+                    yield provider_message.Message(
+                        role='assistant',
+                        content=output_content,
+                    )
         except Exception as e:
             self.ap.logger.error(f'n8n webhook call exception: {str(e)}')
             raise N8nAPIError(f'n8n webhook call exception: {str(e)}')

src/langbot/pkg/utils/httpclient.py

@@ -0,0 +1,43 @@
+"""Shared aiohttp.ClientSession to avoid repeated SSL context creation.
+
+Each call to `aiohttp.ClientSession()` creates a new `TCPConnector` which in turn
+creates a new `ssl.SSLContext` and loads all system root certificates. This is
+extremely expensive in both CPU and memory (~270MB total allocations observed via
+memray profiling).
+
+This module provides a shared session pool so that all HTTP client code in LangBot
+reuses the same underlying SSL context and connection pool.
+"""
+
+from __future__ import annotations
+
+import aiohttp
+
+_sessions: dict[str, aiohttp.ClientSession] = {}
+
+
+def get_session(*, trust_env: bool = False) -> aiohttp.ClientSession:
+    """Get or create a shared aiohttp.ClientSession.
+
+    Args:
+        trust_env: Whether to trust environment variables for proxy settings.
+
+    Returns:
+        A shared aiohttp.ClientSession instance.
+    """
+    key = f'trust_env={trust_env}'
+
+    session = _sessions.get(key)
+    if session is None or session.closed:
+        session = aiohttp.ClientSession(trust_env=trust_env)
+        _sessions[key] = session
+
+    return session
+
+
+async def close_all():
+    """Close all shared sessions. Call on application shutdown."""
+    for session in _sessions.values():
+        if not session.closed:
+            await session.close()
+    _sessions.clear()

src/langbot/pkg/utils/image.py

@@ -5,6 +5,8 @@ from urllib.parse import urlparse, parse_qs
 import ssl
 
 import aiohttp
+
+from langbot.pkg.utils import httpclient
 import PIL.Image
 import httpx
 
@@ -47,53 +49,54 @@ async def get_gewechat_image_base64(
     )
 
     try:
-        async with aiohttp.ClientSession(timeout=timeout) as session:
-            # 获取图片下载链接
-            try:
-                async with session.post(
-                    f'{gewechat_url}/v2/api/message/downloadImage',
-                    headers=headers,
-                    json={'appId': app_id, 'type': image_type, 'xml': xml_content},
-                ) as response:
-                    if response.status != 200:
-                        # print(response)
-                        raise Exception(f'获取gewechat图片下载失败: {await response.text()}')
+        session = httpclient.get_session()
+        # 获取图片下载链接
+        try:
+            async with session.post(
+                f'{gewechat_url}/v2/api/message/downloadImage',
+                headers=headers,
+                json={'appId': app_id, 'type': image_type, 'xml': xml_content},
+                timeout=timeout,
+            ) as response:
+                if response.status != 200:
+                    # print(response)
+                    raise Exception(f'获取gewechat图片下载失败: {await response.text()}')
 
-                    resp_data = await response.json()
-                    if resp_data.get('ret') != 200:
-                        raise Exception(f'获取gewechat图片下载链接失败: {resp_data}')
+                resp_data = await response.json()
+                if resp_data.get('ret') != 200:
+                    raise Exception(f'获取gewechat图片下载链接失败: {resp_data}')
 
-                    file_url = resp_data['data']['fileUrl']
-            except asyncio.TimeoutError:
-                raise Exception('获取图片下载链接超时')
-            except aiohttp.ClientError as e:
-                raise Exception(f'获取图片下载链接网络错误: {str(e)}')
+                file_url = resp_data['data']['fileUrl']
+        except asyncio.TimeoutError:
+            raise Exception('获取图片下载链接超时')
+        except aiohttp.ClientError as e:
+            raise Exception(f'获取图片下载链接网络错误: {str(e)}')
 
-            # 解析原始URL并替换端口
-            base_url = gewechat_file_url
-            download_url = f'{base_url}/download/{file_url}'
+        # 解析原始URL并替换端口
+        base_url = gewechat_file_url
+        download_url = f'{base_url}/download/{file_url}'
 
-            # 下载图片
-            try:
-                async with session.get(download_url) as img_response:
-                    if img_response.status != 200:
-                        raise Exception(f'下载图片失败: {await img_response.text()}, URL: {download_url}')
+        # 下载图片
+        try:
+            async with session.get(download_url) as img_response:
+                if img_response.status != 200:
+                    raise Exception(f'下载图片失败: {await img_response.text()}, URL: {download_url}')
 
-                    image_data = await img_response.read()
+                image_data = await img_response.read()
 
-                    content_type = img_response.headers.get('Content-Type', '')
-                    if content_type:
-                        image_format = content_type.split('/')[-1]
-                    else:
-                        image_format = file_url.split('.')[-1]
+                content_type = img_response.headers.get('Content-Type', '')
+                if content_type:
+                    image_format = content_type.split('/')[-1]
+                else:
+                    image_format = file_url.split('.')[-1]
 
-                    base64_str = base64.b64encode(image_data).decode('utf-8')
+                base64_str = base64.b64encode(image_data).decode('utf-8')
 
-                    return base64_str, image_format
-            except asyncio.TimeoutError:
-                raise Exception(f'下载图片超时, URL: {download_url}')
-            except aiohttp.ClientError as e:
-                raise Exception(f'下载图片网络错误: {str(e)}, URL: {download_url}')
+                return base64_str, image_format
+        except asyncio.TimeoutError:
+            raise Exception(f'下载图片超时, URL: {download_url}')
+        except aiohttp.ClientError as e:
+            raise Exception(f'下载图片网络错误: {str(e)}, URL: {download_url}')
     except Exception as e:
         raise Exception(f'获取图片失败: {str(e)}') from e
 
@@ -104,24 +107,24 @@ async def get_wecom_image_base64(pic_url: str) -> tuple[str, str]:
     :param pic_url: 企业微信图片URL
     :return: (base64_str, image_format)
     """
-    async with aiohttp.ClientSession() as session:
-        async with session.get(pic_url) as response:
-            if response.status != 200:
-                raise Exception(f'Failed to download image: {response.status}')
+    session = httpclient.get_session()
+    async with session.get(pic_url) as response:
+        if response.status != 200:
+            raise Exception(f'Failed to download image: {response.status}')
 
-            # 读取图片数据
-            image_data = await response.read()
+        # 读取图片数据
+        image_data = await response.read()
 
-            # 获取图片格式
-            content_type = response.headers.get('Content-Type', '')
-            image_format = content_type.split('/')[-1]  # 例如 'image/jpeg' -> 'jpeg'
+        # 获取图片格式
+        content_type = response.headers.get('Content-Type', '')
+        image_format = content_type.split('/')[-1]  # 例如 'image/jpeg' -> 'jpeg'
 
-            # 转换为 base64
-            import base64
+        # 转换为 base64
+        import base64
 
-            image_base64 = base64.b64encode(image_data).decode('utf-8')
+        image_base64 = base64.b64encode(image_data).decode('utf-8')
 
-            return image_base64, image_format
+        return image_base64, image_format
 
 
 async def get_qq_official_image_base64(pic_url: str, content_type: str) -> tuple[str, str]:
@@ -152,21 +155,19 @@ async def get_qq_image_bytes(image_url: str, query: dict = {}) -> tuple[bytes, s
     ssl_context = ssl.create_default_context()
     ssl_context.check_hostname = False
     ssl_context.verify_mode = ssl.CERT_NONE
-    async with aiohttp.ClientSession(trust_env=False) as session:
-        async with session.get(
-            image_url, params=query, ssl=ssl_context, timeout=aiohttp.ClientTimeout(total=30.0)
-        ) as resp:
-            resp.raise_for_status()
-            file_bytes = await resp.read()
-            content_type = resp.headers.get('Content-Type')
-            if not content_type:
-                image_format = 'jpeg'
-            elif not content_type.startswith('image/'):
-                pil_img = PIL.Image.open(io.BytesIO(file_bytes))
-                image_format = pil_img.format.lower()
-            else:
-                image_format = content_type.split('/')[-1]
-            return file_bytes, image_format
+    session = httpclient.get_session()
+    async with session.get(image_url, params=query, ssl=ssl_context, timeout=aiohttp.ClientTimeout(total=30.0)) as resp:
+        resp.raise_for_status()
+        file_bytes = await resp.read()
+        content_type = resp.headers.get('Content-Type')
+        if not content_type:
+            image_format = 'jpeg'
+        elif not content_type.startswith('image/'):
+            pil_img = PIL.Image.open(io.BytesIO(file_bytes))
+            image_format = pil_img.format.lower()
+        else:
+            image_format = content_type.split('/')[-1]
+        return file_bytes, image_format
 
 
 async def qq_image_url_to_base64(image_url: str) -> typing.Tuple[str, str]:
@@ -204,11 +205,11 @@ async def extract_b64_and_format(image_base64_data: str) -> typing.Tuple[str, st
 async def get_slack_image_to_base64(pic_url: str, bot_token: str):
     headers = {'Authorization': f'Bearer {bot_token}'}
     try:
-        async with aiohttp.ClientSession() as session:
-            async with session.get(pic_url, headers=headers) as resp:
-                mime_type = resp.headers.get('Content-Type', 'application/octet-stream')
-                file_bytes = await resp.read()
-                base64_str = base64.b64encode(file_bytes).decode('utf-8')
-            return f'data:{mime_type};base64,{base64_str}'
+        session = httpclient.get_session()
+        async with session.get(pic_url, headers=headers) as resp:
+            mime_type = resp.headers.get('Content-Type', 'application/octet-stream')
+            file_bytes = await resp.read()
+            base64_str = base64.b64encode(file_bytes).decode('utf-8')
+        return f'data:{mime_type};base64,{base64_str}'
     except Exception as e:
         raise (e)