encode/httpx · error · RuntimeError

Cannot call `raise_for_status` as the request instance has n

Error message

Cannot call `raise_for_status` as the request instance has not been set on this response.

What it means

Raised as `RuntimeError` at the top of `Response.raise_for_status()` when `self._request is None`. `raise_for_status` needs the originating Request to attach to the `HTTPStatusError` it raises, so it bails out early if the link is missing. As with error 40, this indicates a Response that was not produced through the normal send pipeline.

Source

Thrown at httpx/_models.py:800

                # 302 (Uncacheable redirect. Method may change to GET.)
                codes.FOUND,
                # 303 (Client should make a GET or HEAD request.)
                codes.SEE_OTHER,
                # 307 (Equiv. 302, but retain method)
                codes.TEMPORARY_REDIRECT,
                # 308 (Equiv. 301, but retain method)
                codes.PERMANENT_REDIRECT,
            )
            and "Location" in self.headers
        )

    def raise_for_status(self) -> Response:
        """
        Raise the `HTTPStatusError` if one occurred.
        """
        request = self._request
        if request is None:
            raise RuntimeError(
                "Cannot call `raise_for_status` as the request "
                "instance has not been set on this response."
            )

        if self.is_success:
            return self

        if self.has_redirect_location:
            message = (
                "{error_type} '{0.status_code} {0.reason_phrase}' for url '{0.url}'\n"
                "Redirect location: '{0.headers[location]}'\n"
                "For more information check: https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/{0.status_code}"
            )
        else:
            message = (
                "{error_type} '{0.status_code} {0.reason_phrase}' for url '{0.url}'\n"
                "For more information check: https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/{0.status_code}"
            )

View on GitHub (pinned to b5addb64f0)

Solutions

1. Construct the Response with a request: `httpx.Response(404, request=httpx.Request('GET', url))` before calling `raise_for_status()`.
2. Use `httpx.MockTransport` to fabricate responses so the request link is populated automatically.
3. Guard the call: `if getattr(response, '_request', None) is not None: response.raise_for_status()`.
4. In custom transports, always set `response.request = request` before returning.

Example fix

// before
resp = httpx.Response(404)
resp.raise_for_status()  # RuntimeError

// after
req = httpx.Request('GET', 'https://example.com/')
resp = httpx.Response(404, request=req)
resp.raise_for_status()  # HTTPStatusError, as intended

def can_raise(resp: httpx.Response) -> bool:
    return getattr(resp, '_request', None) is not None

import httpx

def response_has_request(resp: httpx.Response) -> bool:
    return getattr(resp, '_request', None) is not None

try:
    response.raise_for_status()
except RuntimeError:
    # no request attached - reattach or handle synthetically
    response.request = httpx.Request('GET', 'https://example.com/')
    response.raise_for_status()

When it happens

Trigger: Calling `httpx.Response(404).raise_for_status()` on a hand-built Response, or calling `raise_for_status()` on a Response returned by a custom transport that did not set `request=`.

Common situations: Tests with synthetic error responses; custom transports / mocks that emulate server errors without wiring the request; middleware that wraps and rebuilds Responses.

Related errors

• The request instance has not been set on this response.
• '.elapsed' may only be accessed after the response has been
• Attempted to access streaming response content, without havi
• Attempted to read or stream some content, but the content ha
• Attempted to read or stream content, but the stream has been

AI-assisted analysis of encode/httpx@b5addb64f0 (2026-08-04). Data as JSON: /data/errors/aeb248bf4985e8bf.json. Report an issue: GitHub.