fastapi ValueError: raw stream has been detached
fastapi ValueError: raw stream has been detached
我的 api 从客户端正常工作，因为它 returns 预期响应，但令我困扰的是我从服务器端收到如下日志记录错误。我没弄清楚这个错误是什么以及如何防止这种情况发生。
代码未附加，因为错误似乎与我的实现无关。
--- Logging error ---
Traceback (most recent call last):
File "/usr/lib/python3.8/logging/__init__.py", line 1088, in emit
stream.write(msg + self.terminator)
File "/usr/lib/python3.8/codecs.py", line 378, in write
self.stream.write(data)
ValueError: raw stream has been detached
Call stack:
File "<string>", line 1, in <module>
File "/usr/lib/python3.8/multiprocessing/spawn.py", line 116, in spawn_main
exitcode = _main(fd, parent_sentinel)
File "/usr/lib/python3.8/multiprocessing/spawn.py", line 129, in _main
return self._bootstrap(parent_sentinel)
File "/usr/lib/python3.8/multiprocessing/process.py", line 315, in _bootstrap
self.run()
File "/usr/lib/python3.8/multiprocessing/process.py", line 108, in run
self._target(*self._args, **self._kwargs)
File "/usr/local/lib/python3.8/dist-packages/uvicorn/subprocess.py", line 76, in subprocess_started
target(sockets=sockets)
File "/usr/local/lib/python3.8/dist-packages/uvicorn/server.py", line 68, in run
return asyncio.run(self.serve(sockets=sockets))
File "/usr/lib/python3.8/asyncio/runners.py", line 44, in run
return loop.run_until_complete(main)
File "/usr/lib/python3.8/asyncio/base_events.py", line 603, in run_until_complete
self.run_forever()
File "/usr/lib/python3.8/asyncio/base_events.py", line 570, in run_forever
self._run_once()
File "/usr/lib/python3.8/asyncio/base_events.py", line 1859, in _run_once
handle._run()
File "/usr/lib/python3.8/asyncio/events.py", line 81, in _run
self._context.run(self._callback, *self._args)
File "/usr/local/lib/python3.8/dist-packages/uvicorn/protocols/http/h11_impl.py", line 373, in run_asgi
result = await app(self.scope, self.receive, self.send)
File "/usr/local/lib/python3.8/dist-packages/uvicorn/middleware/proxy_headers.py", line 75, in __call__
return await self.app(scope, receive, send)
File "/usr/local/lib/python3.8/dist-packages/fastapi/applications.py", line 208, in __call__
await super().__call__(scope, receive, send)
File "/usr/local/lib/python3.8/dist-packages/starlette/applications.py", line 112, in __call__
await self.middleware_stack(scope, receive, send)
File "/usr/local/lib/python3.8/dist-packages/starlette/middleware/errors.py", line 159, in __call__
await self.app(scope, receive, _send)
File "/usr/local/lib/python3.8/dist-packages/starlette/exceptions.py", line 71, in __call__
await self.app(scope, receive, sender)
File "/usr/local/lib/python3.8/dist-packages/starlette/routing.py", line 656, in __call__
await route.handle(scope, receive, send)
File "/usr/local/lib/python3.8/dist-packages/starlette/routing.py", line 259, in handle
await self.app(scope, receive, send)
File "/usr/local/lib/python3.8/dist-packages/starlette/routing.py", line 64, in app
await response(scope, receive, send)
File "/usr/local/lib/python3.8/dist-packages/starlette/responses.py", line 149, in __call__
await send(
File "/usr/local/lib/python3.8/dist-packages/starlette/exceptions.py", line 68, in sender
await send(message)
File "/usr/local/lib/python3.8/dist-packages/starlette/middleware/errors.py", line 156, in _send
await send(message)
File "/usr/local/lib/python3.8/dist-packages/uvicorn/protocols/http/h11_impl.py", line 438, in send
self.access_logger.info(
Message: '%s - "%s %s HTTP/%s" %d'
Arguments: ('xxx.xxx.x.x:35100', 'GET', '/api/myapi', '1.1', 200)
附加信息
$ python --version
Python 3.8.10
$ cat /etc/*ease
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=20.04
DISTRIB_CODENAME=focal
DISTRIB_DESCRIPTION="Ubuntu 20.04.1 LTS"
NAME="Ubuntu"
VERSION="20.04.1 LTS (Focal Fossa)"
ID=ubuntu
ID_LIKE=debian
PRETTY_NAME="Ubuntu 20.04.1 LTS"
VERSION_ID="20.04"
HOME_URL="https://www.ubuntu.com/"
SUPPORT_URL="https://help.ubuntu.com/"
BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
VERSION_CODENAME=focal
UBUNTU_CODENAME=focal
复制错误的最小示例。
from bisect import bisect_right
from collections import defaultdict
from datetime import datetime, timedelta
import json
from operator import ge
import sys
from pathlib import Path
import codecs
sys.stdout = codecs.getwriter("utf-8")(sys.stdout.detach())
from pprint import pprint
from typing import Optional, Set, List, Type, Dict
import inspect
import uvicorn
from fastapi import FastAPI, Request, Response
from pydantic import BaseModel
from fastapi import Form, Depends
app = FastAPI()
fake_items_db = [{"item_name": "Foo"}, {"item_name": "Bar"}, {"item_name": "Baz"}]
@app.get("/items/")
def read_item(skip: int = 0, limit: int = 10):
breakpoint()
return fake_items_db[skip : skip + limit]
不看代码就很难找出问题所在。该错误似乎是指底层缓冲区与 TextIOBase 分离。在调用 f.buffer.detach() 之后调用 f.close() 后，下面的代码会抛出完全相同的错误（即 ValueError: raw stream has been detached）。如果您注释掉 f.close()，您将不会看到该错误。就像我说的，如果提供了代码，人们将能够更好地提供帮助。但是，从下面看，这似乎不是 fastapi 问题，而是 - 从您提供的回溯判断，即 ...File "/usr/lib/python3.8/codecs.py", line 378, in write self.stream.write(data) ValueError: raw stream has been detached - 似乎是用于记录消息或我们看不到的东西；也许，在缓冲区已分离时尝试关闭文件。
f = open ('text.txt', 'w')
for i in range(1,15):
f.write(str(i))
buff = f.buffer.detach()
#print(buff)
f.close()
我的 api 从客户端正常工作，因为它 returns 预期响应，但令我困扰的是我从服务器端收到如下日志记录错误。我没弄清楚这个错误是什么以及如何防止这种情况发生。
代码未附加，因为错误似乎与我的实现无关。
--- Logging error ---
Traceback (most recent call last):
File "/usr/lib/python3.8/logging/__init__.py", line 1088, in emit
stream.write(msg + self.terminator)
File "/usr/lib/python3.8/codecs.py", line 378, in write
self.stream.write(data)
ValueError: raw stream has been detached
Call stack:
File "<string>", line 1, in <module>
File "/usr/lib/python3.8/multiprocessing/spawn.py", line 116, in spawn_main
exitcode = _main(fd, parent_sentinel)
File "/usr/lib/python3.8/multiprocessing/spawn.py", line 129, in _main
return self._bootstrap(parent_sentinel)
File "/usr/lib/python3.8/multiprocessing/process.py", line 315, in _bootstrap
self.run()
File "/usr/lib/python3.8/multiprocessing/process.py", line 108, in run
self._target(*self._args, **self._kwargs)
File "/usr/local/lib/python3.8/dist-packages/uvicorn/subprocess.py", line 76, in subprocess_started
target(sockets=sockets)
File "/usr/local/lib/python3.8/dist-packages/uvicorn/server.py", line 68, in run
return asyncio.run(self.serve(sockets=sockets))
File "/usr/lib/python3.8/asyncio/runners.py", line 44, in run
return loop.run_until_complete(main)
File "/usr/lib/python3.8/asyncio/base_events.py", line 603, in run_until_complete
self.run_forever()
File "/usr/lib/python3.8/asyncio/base_events.py", line 570, in run_forever
self._run_once()
File "/usr/lib/python3.8/asyncio/base_events.py", line 1859, in _run_once
handle._run()
File "/usr/lib/python3.8/asyncio/events.py", line 81, in _run
self._context.run(self._callback, *self._args)
File "/usr/local/lib/python3.8/dist-packages/uvicorn/protocols/http/h11_impl.py", line 373, in run_asgi
result = await app(self.scope, self.receive, self.send)
File "/usr/local/lib/python3.8/dist-packages/uvicorn/middleware/proxy_headers.py", line 75, in __call__
return await self.app(scope, receive, send)
File "/usr/local/lib/python3.8/dist-packages/fastapi/applications.py", line 208, in __call__
await super().__call__(scope, receive, send)
File "/usr/local/lib/python3.8/dist-packages/starlette/applications.py", line 112, in __call__
await self.middleware_stack(scope, receive, send)
File "/usr/local/lib/python3.8/dist-packages/starlette/middleware/errors.py", line 159, in __call__
await self.app(scope, receive, _send)
File "/usr/local/lib/python3.8/dist-packages/starlette/exceptions.py", line 71, in __call__
await self.app(scope, receive, sender)
File "/usr/local/lib/python3.8/dist-packages/starlette/routing.py", line 656, in __call__
await route.handle(scope, receive, send)
File "/usr/local/lib/python3.8/dist-packages/starlette/routing.py", line 259, in handle
await self.app(scope, receive, send)
File "/usr/local/lib/python3.8/dist-packages/starlette/routing.py", line 64, in app
await response(scope, receive, send)
File "/usr/local/lib/python3.8/dist-packages/starlette/responses.py", line 149, in __call__
await send(
File "/usr/local/lib/python3.8/dist-packages/starlette/exceptions.py", line 68, in sender
await send(message)
File "/usr/local/lib/python3.8/dist-packages/starlette/middleware/errors.py", line 156, in _send
await send(message)
File "/usr/local/lib/python3.8/dist-packages/uvicorn/protocols/http/h11_impl.py", line 438, in send
self.access_logger.info(
Message: '%s - "%s %s HTTP/%s" %d'
Arguments: ('xxx.xxx.x.x:35100', 'GET', '/api/myapi', '1.1', 200)
附加信息
$ python --version
Python 3.8.10
$ cat /etc/*ease
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=20.04
DISTRIB_CODENAME=focal
DISTRIB_DESCRIPTION="Ubuntu 20.04.1 LTS"
NAME="Ubuntu"
VERSION="20.04.1 LTS (Focal Fossa)"
ID=ubuntu
ID_LIKE=debian
PRETTY_NAME="Ubuntu 20.04.1 LTS"
VERSION_ID="20.04"
HOME_URL="https://www.ubuntu.com/"
SUPPORT_URL="https://help.ubuntu.com/"
BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
VERSION_CODENAME=focal
UBUNTU_CODENAME=focal
复制错误的最小示例。
from bisect import bisect_right
from collections import defaultdict
from datetime import datetime, timedelta
import json
from operator import ge
import sys
from pathlib import Path
import codecs
sys.stdout = codecs.getwriter("utf-8")(sys.stdout.detach())
from pprint import pprint
from typing import Optional, Set, List, Type, Dict
import inspect
import uvicorn
from fastapi import FastAPI, Request, Response
from pydantic import BaseModel
from fastapi import Form, Depends
app = FastAPI()
fake_items_db = [{"item_name": "Foo"}, {"item_name": "Bar"}, {"item_name": "Baz"}]
@app.get("/items/")
def read_item(skip: int = 0, limit: int = 10):
breakpoint()
return fake_items_db[skip : skip + limit]
不看代码就很难找出问题所在。该错误似乎是指底层缓冲区与 TextIOBase 分离。在调用 f.buffer.detach() 之后调用 f.close() 后，下面的代码会抛出完全相同的错误（即 ValueError: raw stream has been detached）。如果您注释掉 f.close()，您将不会看到该错误。就像我说的，如果提供了代码，人们将能够更好地提供帮助。但是，从下面看，这似乎不是 fastapi 问题，而是 - 从您提供的回溯判断，即 ...File "/usr/lib/python3.8/codecs.py", line 378, in write self.stream.write(data) ValueError: raw stream has been detached - 似乎是用于记录消息或我们看不到的东西；也许，在缓冲区已分离时尝试关闭文件。
f = open ('text.txt', 'w')
for i in range(1,15):
f.write(str(i))
buff = f.buffer.detach()
#print(buff)
f.close()