Fiddler Ideas

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Raw response view doesn't show HTTP content if the content length header is wrong.

I was debugging a failing web request and it transpired that the HTTP response headers were corrupted, such that the content length field specified a length longer than the actual content.

Hence fiddller was waiting for that extra content, and, after some timeout, fiddler reports how many bytes were expected and how many were received, but it doesn't show the received bytes/content, which would have been useful.


  • Guest
  • Feb 3 2017
  • Under review
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  • Eric Lawrence commented
    3 Feb, 2017 04:09pm

    Was the content in the response area:

    [Fiddler] ReadResponse() failed: The server did not return a complete response for this request. Server returned #### bytes.

    If so, yeah, I thought I'd already made a tweak here, but it looks like I didn't get to it before I left.

    The problem is that we don't want to return the partial response to the client because it might mistake it for the real response, and we don't want Fiddler's UI to be misleading in showing the partial response (because when buffering is enabled, the bytes it returns are the error, not the partial response).

    At a minimum, Fiddler should probably store the partial response as a base64-encoded flag on the Session (assuming that they're not *crazy* huge), as this will make it easier for WebDevs who are working with broken HTTP implementations to figure out what's going wrong. Fiddler might  consider augmenting the error message ("... and here are the last 2048 bytes of that partial response: xxxxxxxx").