Aiohttp client throws an error serverdisconnectederror server disconnected - Исправление ошибок и поиск оптимальных решений проблем

I had similar problem and I was hoping that aiohttp could have a retry logic on connection errors and possible on HTTP status. Because there isn’t just thing yet available I came up with the following which works for REST APIs where json is returned::

HTTP_STATUS_CODES_TO_RETRY = [500, 502, 503, 504]
class FailedRequest(Exception):
    """
    A wrapper of all possible exception during a HTTP request
    """
    code = 0
    message = ''
    url = ''
    raised = ''

    def __init__(self, *, raised='', message='', code='', url=''):
        self.raised = raised
        self.message = message
        self.code = code
        self.url = url

        super().__init__("code:{c} url={u} message={m} raised={r}".format(
            c=self.code, u=self.url, m=self.message, r=self.raised))


async def send_http(session, method, url, *,
                    retries=1,
                    interval=0.9,
                    backoff=3,
                    read_timeout=15.9,
                    http_status_codes_to_retry=HTTP_STATUS_CODES_TO_RETRY,
                    **kwargs):
    """
    Sends a HTTP request and implements a retry logic.

    Arguments:
        session (obj): A client aiohttp session object
        method (str): Method to use
        url (str): URL for the request
        retries (int): Number of times to retry in case of failure
        interval (float): Time to wait before retries
        backoff (int): Multiply interval by this factor after each failure
        read_timeout (float): Time to wait for a response
    """
    backoff_interval = interval
    raised_exc = None
    attempt = 0

    if method not in ['get', 'patch', 'post']:
        raise ValueError

    if retries == -1:  # -1 means retry indefinitely
        attempt = -1
    elif retries == 0: # Zero means don't retry
        attempt = 1
    else:  # any other value means retry N times
        attempt = retries + 1

    while attempt != 0:
        if raised_exc:
            log.error('caught "%s" url:%s method:%s, remaining tries %s, '
                    'sleeping %.2fsecs', raised_exc, method.upper(), url,
                    attempt, backoff_interval)
            await asyncio.sleep(backoff_interval)
            # bump interval for the next possible attempt
            backoff_interval = backoff_interval * backoff
        log.info('sending %s %s with %s', method.upper(), url, kwargs)
        try:
            with aiohttp.Timeout(timeout=read_timeout):
                async with getattr(session, method)(url, **kwargs) as response:
                    if response.status == 200:
                        try:
                            data = await response.json()
                        except json.decoder.JSONDecodeError as exc:
                            log.error(
                                'failed to decode response code:%s url:%s '
                                'method:%s error:%s response:%s',
                                response.status, url, method.upper(), exc,
                                response.reason
                            )
                            raise aiohttp.errors.HttpProcessingError(
                                code=response.status, message=exc.msg)
                        else:
                            log.info('code:%s url:%s method:%s response:%s',
                                    response.status, url, method.upper(),
                                    response.reason)
                            raised_exc = None
                            return data
                    elif response.status in http_status_codes_to_retry:
                        log.error(
                            'received invalid response code:%s url:%s error:%s'
                            ' response:%s', response.status, url, '',
                            response.reason
                        )
                        raise aiohttp.errors.HttpProcessingError(
                            code=response.status, message=response.reason)
                    else:
                        try:
                            data = await response.json()
                        except json.decoder.JSONDecodeError as exc:
                            log.error(
                                'failed to decode response code:%s url:%s '
                                'error:%s response:%s', response.status, url,
                                exc, response.reason
                            )
                            raise FailedRequest(
                                code=response.status, message=exc,
                                raised=exc.__class__.__name__, url=url)
                        else:
                            log.warning('received %s for %s', data, url)
                            print(data['errors'][0]['detail'])
                            raised_exc = None
        except (aiohttp.errors.ClientResponseError,
                aiohttp.errors.ClientRequestError,
                aiohttp.errors.ClientOSError,
                aiohttp.errors.ClientDisconnectedError,
                aiohttp.errors.ClientTimeoutError,
                asyncio.TimeoutError,
                aiohttp.errors.HttpProcessingError) as exc:
            try:
                code = exc.code
            except AttributeError:
                code = ''
            raised_exc = FailedRequest(code=code, message=exc, url=url,
                                    raised=exc.__class__.__name__)
        else:
            raised_exc = None
            break

        attempt -= 1

    if raised_exc:
        raise raised_exc

Источник

Содержание

ServerDisconnectedError on subsequent requests only on Py 3.8 #4549
Comments
aiohttp client_exception ServerDisconnectedError — это проблема сервера API, aiohttp или моего кода?
3 ответа
Connection Reset by peer error using aiohttp and asyncio #5969
<>’s edit
Describe the bug
To Reproduce
Expected behavior
Logs/tracebacks
Python Version
aiohttp Version
multidict Version
yarl Version
Related component
Additional context
Code of Conduct
Replies: 2 suggested answers · 4 replies
Client Reference¶
Client Session¶
Basic API¶
Connectors¶
BaseConnector¶
TCPConnector¶
UnixConnector¶
Connection¶
Response object¶
ClientWebSocketResponse¶
Utilities¶
ClientTimeout¶
RequestInfo¶
BasicAuth¶
CookieJar¶
FormData¶
Client exceptions¶
Response errors¶
Connection errors¶

ServerDisconnectedError on subsequent requests only on Py 3.8 #4549

🐞 Describe the bug

Aiohttp throws aiohttp.ServerDisconnectedError on 3.8.1 on subsequent requests within scope of single ClientSession, but only on certain domains. There is no such issue on older Python 3.7.6 so it shouldn’t be issue on remote server.

💡 To Reproduce

Run -> Throws error on second request
Uncomment line await asyncio.sleep(0.0001) (this is just for experimentation, to demonstrate that somehow this issue doesn’t occur when there’s sleep).
Run -> Doesn’t throw error on second request

💡 Expected behavior

Both requests should complete successfully sequentially — just like on Python 3.7.

📋 Logs/tracebacks

📋 Your version of the Python

📋 Your version of the aiohttp/yarl/multidict distributions

📋 Additional context

aiohttp client. Python 3.8.1 (pyenv), venv installed via poetry.

The text was updated successfully, but these errors were encountered:

Looks like this is a good starting point for debugging. Could you please specify a few URLs where this explodes and (separately) a few URLs where it works. Also, is your Python interpreter coming from some public OS distro or did you compile it?

I tried google.com for example, where it worked on 3.8.

As for python interpreter, pyenv, as far as I know, compiles from source. But I tried it on Manjaro/Archlinux’s Python 3.8.1 on which it also failed.

Is this happening to both HTTP and HTTPS URLs?

Yes, it happens on both https and http.

I’ve found the same problem in python 3.8.0 from pyenv.
The problem happens when I try to connect to a server in localhost created with aiohttp.

Why this got tagged with reproducer:missing? I provided code snippet, which I believe highlights the issue clearly enough. Was it not possible to reproduce?
I just tried the same code snippet again, this time on WinPython 3.7.6 and then 3.8.1 and could reproduce the issue.
On Python 3.7.6 the code snippet provided in first post, will print returned response twice. On Python 3.8.1 it will print response only for the first time, followed by aiohttp.client_exceptions.ServerDisconnectedError

I cannot reproduce this issue with the code snippet you provided running with python 3.8.1 on Archlinux, but I do have a similar issue as @gligneul with a test server on localhost.

@Gargauth I don’t remember why exactly but I probably marked is as missing because it looked like it’s not enough. Now that I confirmed that it’s reproducible under 3.8-dev from pyenv (on my Gentoo laptop), I can safely mark it as present.

@Gargauth please provide HTTP URL with this issue happening. Changing your current reproducer URLs to plain HTTP does not explode. This is needed to confirm if it’s related to TLS and it’s what’s unstable about your reproducer ATM.

By the way, the best way to share a reproducer is to contribute a reliably failing test and mark it as @pytest.mark.xfail per https://pganssle-talks.github.io/xfail-lightning. This would allow somebody to start fixing the behavior later and have some indicator if it’s actually fixed.

I got this problem on Python 3.8.4 (Windows) too.
And it’s interesting that I tried to add a await asyncio.sleep(0) which solve the problem.

I am seeing the same error, but on Python 3.6 (Ubuntu 20.04.1 LTS). The first request would succeed, the second would consistently and immediately fail.

Per @WH-2099, await asyncio.sleep(0) fixed the issue.

Using versions:
Python 3.6.13
aiohttp==3.7.4

Does anybody have any other URLs that this happens on? Trying a few URLs, only the one in the reproducer triggered the issue for me.

I see the error with the original code, but await asyncio.sleep(0) doesn’t fix it for me. 0.001 as per the original example works though. This suggests to me that it may be some kind of timing issue with the server. Maybe it disconnects because it’s too fast, or maybe some command is getting sent out of order and the server is aborting.

In fact I spent a lot of time trying to solve the same problem when I intuitively found these three issues.
And I was able to find effective solutions to alleviate (not completely solve) all of them.

In general, I think these issues are clearly related to the change in the Python 3.8 asyncio module to change the default event loop.https://docs.python.org/3/library/asyncio-platforms.html

And the most important feature that manifests itself is premature disconnection from the underlying connection to the server.
Personally, I would suggest that these three issues be investigated in connection, and I am available these days to assist if needed.
(Please excuse my rudimentary English)

In general, I think these issues are clearly related to the change in the Python 3.8 asyncio module to change the default event loop.https://docs.python.org/3/library/asyncio-platforms.html

Not sure if it changes your theory, but I reproduced the example for this on Linux, which is not using the ProactorEventLoop. I did not try testing in Python 3.7 though.

I am experiencing this with Python 3.9.6 running inside Docker container (official Python image, tag 3.9.6-buster ) running on Ubuntu 20.04 LTS (launched in WSL2).

Requests are being sent to:

It is possible to overcome it with asyncio.sleep(0.1) , but it works only if I put it before the second request, not after the first one (they are made in a for loop and there is some user input between iterations, so they are not exactly sequential in terms of time)

And it doesn’t happen with the requests lib.

I can’t reproduce with any of those URLs, still only the original URL.

Also, I’ve just realised I was reproducing it in an lxc container, but I can’t reproduce the issue on my host.

One additional datapoint is that the issue also seems to only appear if reading from the response (i.e. no error when removing resp.text() ).

@Dreamsorcerer Thanks for the reminder, I’m mainly using the windows platform and am not very familiar with linux, so I was not thinking well.

It looks like the event loop is not the culprit.

However, I still intuitively think that these issues may be caused by the same problem at the bottom.

@Dreamsorcerer here is the piece of code which reproduces the issue for me consistently both inside the docker container (Python 3.9.6), on the Ubuntu (WSL, Python 3.8.10) and on the Windows host (Python 3.9.6).

It uses pipenv to manage dependencies, so you want to:

install pipenv
launch the shell: pipenv shell
install dependencies: pipenv install
launch get_token.py

It will be asking you for the username and password — you can enter any random data.
After several retries it will ask you to fill captcha — open the url provided and then again you can enter random data instead of the captcha answer and the password.

After that it tries to login again and gives me ServerDisconnectedError .
Uncommenting sleep lines «fixes» the issue.

Strange that ServerDisconnectedError doesn’t appear for login attempts before the captcha request (but if I remember correctly it fails in case of the correct login without the captcha).
Also, it seems it doesn’t appear if you don’t open the captcha url (the server will reply with another error, that the captcha was not opened).

Источник

aiohttp client_exception ServerDisconnectedError — это проблема сервера API, aiohttp или моего кода?

Я получаю aiohttp client_exception.ServerDisconnectedError всякий раз, когда делаю более

200 запросов к API, который я использую с помощью asyncio и aiohttp. Похоже, это не мой код, потому что он стабильно работает с меньшим количеством запросов, но не работает с любым большим числом. Пытаетесь понять, связана ли эта ошибка с aiohttp, моим кодом или с самой конечной точкой API? Кажется, в Интернете не так много информации по этому поводу.

Вот часть кода для генерации асинхронных запросов:

После завершения задач метод self.load_results() просто анализирует json и обновляет БД.

3 ответа

Я думаю, что вполне возможно, что другие ответы верны, но есть и еще одна возможность — кажется, что у aiohttp есть по крайней мере одно в настоящее время [июнь 2021 г.] неисправленное состояние гонки в коде потоков:

Я вижу ту же проблему в своем проекте, и это достаточно редко (и отключение сервера — не единственный симптом, иногда я получаю «неполная полезная нагрузка»), это больше похоже на состояние гонки.

Я рассматривал возможность перехода на https://www.python-httpx.org в надежде, что это не у меня нет такой же проблемы, но (из-за того, что она в настоящее время все еще находится в бета-версии) еще не решилась на это.

Скорее всего, это вызвано конфигурацией HTTP-сервера. Есть как минимум две возможные причины ServerDisconnectedError:

Сервер может ограничить количество параллельных TCP-подключений, которые можно установить с одного IP-адреса. По умолчанию aiohttp уже ограничивает количество параллельных подключений до 100. Вы можете попробовать уменьшить ограничение и посмотреть, решит ли это проблему. Для этого вы можете создать пользовательский TCPConnector с другим предельным значением и передать его в ClientSession :

Сервер может ограничить продолжительность TCP-соединения. По умолчанию aiohttp использует поддержку активности HTTP, чтобы одно и то же соединение TCP можно было использовать для нескольких запросов. Это повышает производительность, поскольку для каждого запроса не требуется устанавливать новое TCP-соединение. Однако некоторые серверы ограничивают продолжительность TCP-соединения, и если вы используете одно и то же TCP-соединение для многих запросов, сервер может закрыть его до того, как вы закончите с ним. Вы можете отключить поддержку активности HTTP в качестве обходного пути. Для этого вы можете создать пользовательский TCPConnector с параметром force_close , установленным на True , и передать его в ClientSession :

У меня была та же проблема, и отключение поддержки активности HTTP было для меня решением. Надеюсь это поможет.

Скорее всего, API сервера не устраивает несколько запросов, выполняемых асинхронно. Вы можете ограничить количество одновременных вызовов с помощью семафоров asyncio. .

В вашем случае я бы использовал его в менеджере контекста как:

Источник

Connection Reset by peer error using aiohttp and asyncio #5969

<>’s edit

Describe the bug

I am getting aiohttp.client_exceptions.ClientConnectorError upon using aiohttp and asyncio together. I am gathering all tasks using one session by aiohttp and getting responses.

To Reproduce

Expected behavior

Tasks executed in queue with status code 200.

Logs/tracebacks

Python Version

aiohttp Version

multidict Version

yarl Version

macOS — Darwin Kernel Version 19.6.0

Additional context

Code of Conduct

I agree to follow the aio-libs Code of Conduct

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[Errno 54] Connection reset by peer

This means that the server drops connections on the TCP level. Maybe because you’re spamming them. Verify that with the server side. There’s nothing we can do.

You could wrap tasks with try/except catching ClientConnectorError in order to ignore or retry after some backoff but that’s it.

[Errno 54] Connection reset by peer

This means that the server drops connections on the TCP level. Maybe because you’re spamming them. Verify that with the server side. There’s nothing we can do.

You could wrap tasks with try/except catching ClientConnectorError in order to ignore or retry after some backoff but that’s it.

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Marked as answer

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Thanks mate for prompt response. Let me check further on this

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[Errno 54] Connection reset by peer

This means that the server drops connections on the TCP level. Maybe because you’re spamming them. Verify that with the server side. There’s nothing we can do.

You could wrap tasks with try/except catching ClientConnectorError in order to ignore or retry after some backoff but that’s it.

Is there a specific cooldown for this? I’m having this issue for the first time now. It’s a loop which does a specific task every 5 minutes.
Versions are similar to the one created this thread.

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Client Reference¶

Client Session¶

Client session is the recommended interface for making HTTP requests.

Session encapsulates a connection pool (connector instance) and supports keepalives by default. Unless you are connecting to a large, unknown number of different servers over the lifetime of your application, it is suggested you use a single session for the lifetime of your application to benefit from connection pooling.

The client session supports the context manager protocol for self closing.

class aiohttp. ClientSession ( base_url = None , * , connector = None , cookies = None , headers = None , skip_auto_headers = None , auth = None , json_serialize = json.dumps , version = aiohttp.HttpVersion11 , cookie_jar = None , read_timeout = None , conn_timeout = None , timeout = sentinel , raise_for_status = False , connector_owner = True , auto_decompress = True , read_bufsize = 2**16 , requote_redirect_url = False , trust_env = False , trace_configs = None ) [source] ¶

The class for creating client sessions and making requests.

base_url –

Base part of the URL (optional) If set it allows to skip the base part in request calls.

New in version 3.8.

connector (aiohttp.BaseConnector) – BaseConnector sub-class instance to support connection pooling.

loop –

event loop used for processing HTTP requests.

If loop is None the constructor borrows it from connector if specified.

asyncio.get_event_loop() is used for getting default event loop otherwise.

Deprecated since version 2.0.

cookies (dict) – Cookies to send with the request (optional)

headers –

HTTP Headers to send with every request (optional).

May be either iterable of key-value pairs or Mapping (e.g. dict , CIMultiDict ).

skip_auto_headers –

set of headers for which autogeneration should be skipped.

aiohttp autogenerates headers like User-Agent or Content-Type if these headers are not explicitly passed. Using skip_auto_headers parameter allows to skip that generation. Note that Content-Length autogeneration can’t be skipped.

Iterable of str or istr (optional)

auth (aiohttp.BasicAuth) – an object that represents HTTP Basic Authorization (optional)

version – supported HTTP version, HTTP 1.1 by default.

cookie_jar –

By default every session instance has own private cookie jar for automatic cookies processing but user may redefine this behavior by providing own jar implementation.

One example is not processing cookies at all when working in proxy mode.

If no cookie processing is needed, a aiohttp.DummyCookieJar instance can be provided.

Json serializer callable.

By default json.dumps() function.

raise_for_status (bool) –

Automatically call ClientResponse.raise_for_status() for each response, False by default.

This parameter can be overridden when you making a request, e.g.:

Set the parameter to True if you need raise_for_status for most of cases but override raise_for_status for those requests where you need to handle responses with status 400 or higher.

timeout – a ClientTimeout settings structure, 300 seconds (5min)

total timeout by default.

New in version 3.3.

Request operations timeout. read_timeout is cumulative for all request operations (request, redirects, responses, data consuming). By default, the read timeout is 5*60 seconds. Use None or 0 to disable timeout checks.

Deprecated since version 3.3: Use timeout parameter instead.

timeout for connection establishing (optional). Values 0 or None mean no timeout.

Deprecated since version 3.3: Use timeout parameter instead.

connector_owner (bool) –

Close connector instance on session closing.

Setting the parameter to False allows to share connection pool between sessions without sharing session state: cookies etc.

auto_decompress (bool) – Automatically decompress response body,

True by default

New in version 2.3.

read_bufsize (int) – Size of the read buffer ( ClientResponse.content ).

64 KiB by default.

New in version 3.7.

Get proxies information from HTTP_PROXY / HTTPS_PROXY environment variables if the parameter is True ( False by default).

Get proxy credentials from

/.netrc file if present.

New in version 2.3.

Changed in version 3.0: Added support for

requote_redirect_url (bool) – Apply URL requoting for redirection URLs if

automatic redirection is enabled ( True by default).

New in version 3.5.

trace_configs – A list of TraceConfig instances used for client tracing. None (default) is used for request tracing disabling. See Tracing Reference for more information.

True if the session has been closed, False otherwise.

A read-only property.

aiohttp.BaseConnector derived instance used for the session.

A read-only property.

The session cookies, AbstractCookieJar instance.

Gives access to cookie jar’s content and modifiers.

A read-only property.

aiohttp re quote’s redirect urls by default, but some servers require exact url from location header. To disable re-quote system set requote_redirect_url attribute to False .

New in version 2.1.

This parameter affects all subsequent requests.

Deprecated since version 3.5: The attribute modification is deprecated.

A loop instance used for session creation.

A read-only property.

Deprecated since version 3.5.

Default client timeouts, ClientTimeout instance. The value can be tuned by passing timeout parameter to ClientSession constructor.

New in version 3.7.

HTTP Headers that sent with every request

May be either iterable of key-value pairs or Mapping (e.g. dict , CIMultiDict ).

New in version 3.7.

Set of headers for which autogeneration skipped.

New in version 3.7.

An object that represents HTTP Basic Authorization.

New in version 3.7.

Json serializer callable.

By default json.dumps() function.

New in version 3.7.

Should connector be closed on session closing

New in version 3.7.

Should ClientResponse.raise_for_status() be called for each response

New in version 3.7.

Should the body response be automatically decompressed

bool default is True

New in version 3.7.

Should get proxies information from HTTP_PROXY / HTTPS_PROXY environment variables or

/.netrc file if present

bool default is False

New in version 3.7.

A list of TraceConfig instances used for client tracing. None (default) is used for request tracing disabling. See Tracing Reference for more information.

New in version 3.7.

Performs an asynchronous HTTP request. Returns a response object.

method (str) – HTTP method

url – Request URL, str or URL .

params –

Mapping, iterable of tuple of key/value pairs or string to be sent as parameters in the query string of the new request. Ignored for subsequent redirected requests (optional)

Allowed values are:

str with preferably url-encoded content (Warning: content will not be encoded by aiohttp)

data – The data to send in the body of the request. This can be a FormData object or anything that can be passed into FormData , e.g. a dictionary, bytes, or file-like object. (optional)

json – Any json compatible python object (optional). json and data parameters could not be used at the same time.

cookies (dict) – HTTP Cookies to send with

the request (optional)

Global session cookies and the explicitly set cookies will be merged when sending the request.

New in version 3.5.

headers (dict) – HTTP Headers to send with the request (optional)

skip_auto_headers –

set of headers for which autogeneration should be skipped.

aiohttp autogenerates headers like User-Agent or Content-Type if these headers are not explicitly passed. Using skip_auto_headers parameter allows to skip that generation.

Iterable of str or istr (optional)

auth (aiohttp.BasicAuth) – an object that represents HTTP Basic Authorization (optional)

allow_redirects (bool) – If set to False , do not follow redirects. True by default (optional).

max_redirects (int) – Maximum number of redirects to follow. 10 by default.

compress (bool) – Set to True if request has to be compressed with deflate encoding. If compress can not be combined with a Content-Encoding and Content-Length headers. None by default (optional).

chunked (int) – Enable chunked transfer encoding. It is up to the developer to decide how to chunk data streams. If chunking is enabled, aiohttp encodes the provided chunks in the “Transfer-encoding: chunked” format. If chunked is set, then the Transfer-encoding and content-length headers are disallowed. None by default (optional).

expect100 (bool) – Expect 100-continue response from server. False by default (optional).

raise_for_status (bool) – Automatically call ClientResponse.raise_for_status() for

response if set to True . If set to None value from ClientSession will be used. None by default (optional).

New in version 3.4.

read_until_eof (bool) – Read response until EOF if response does not have Content-Length header. True by default (optional).

read_bufsize (int) – Size of the read buffer ( ClientResponse.content ).

None by default, it means that the session global value is used.

New in version 3.7.

proxy – Proxy URL, str or URL (optional)

proxy_auth (aiohttp.BasicAuth) – an object that represents proxy HTTP Basic Authorization (optional)

override the session’s timeout.

Changed in version 3.3: The parameter is ClientTimeout instance, float is still supported for sake of backward compatibility.

If float is passed it is a total timeout (in seconds).

ssl – SSL validation mode. None for default SSL check

( ssl.create_default_context() is used), False for skip SSL certificate validation, aiohttp.Fingerprint for fingerprint validation, ssl.SSLContext for custom SSL certificate validation.

Supersedes verify_ssl, ssl_context and fingerprint parameters.

New in version 3.0.

Perform SSL certificate validation for HTTPS requests (enabled by default). May be disabled to skip validation for sites with invalid certificates.

New in version 2.3.

Deprecated since version 3.0: Use ssl=False

Pass the SHA256 digest of the expected certificate in DER format to verify that the certificate the server presents matches. Useful for certificate pinning.

Warning: use of MD5 or SHA1 digests is insecure and removed.

New in version 2.3.

Deprecated since version 3.0: Use ssl=aiohttp.Fingerprint(digest)

ssl context used for processing HTTPS requests (optional).

ssl_context may be used for configuring certification authority channel, supported SSL options etc.

New in version 2.3.

Deprecated since version 3.0: Use ssl=ssl_context

HTTP headers to send to the proxy if the parameter proxy has been provided.

New in version 2.3.

trace_request_ctx –

Object used to give as a kw param for each new TraceConfig object instantiated, used to give information to the tracers that is only available at request time.

New in version 3.0.

coroutine async-with get ( url , * , allow_redirects = True , ** kwargs ) [source] ¶

Perform a GET request.