QNetworkReply and QNetworAccessManager don't emit `finished` signal

xueqli

@Ronel_qtmaster unfortunately, that didn't help

xueqli

For now I'm pretty sure that this is related to QTBUG-122281, because when I connect the metaDataChanged signal and look into reply's headers, they contain information about the invalid token, but nothing happens after

SGaist

@xueqli just to rule out the obvious, you have the same issue if you send requests to a different service ?

Is there one that is accessible that you can share for testing purposes so we can test it ?

xueqli

@SGaist hmm, I haven't encountered this issue for other services
At first I thought that the problem is with www-authenticate header field
So I found the API which also sends it (https://registry-1.docker.io/v2/_catalog, for example), and it works fine (my API sends some other attributes in www-authenticate header, but they are all valid)

The other difference I noticed, my API doesn't send any content (answer.content == b''), and all API I've tried so far send a non-empty error message, so maybe my problem lies here

xueqli

i don't know, looks like it stuck somewhere in the QIODevice::read?

(Pdb) self.reply.isOpen()
True
(Pdb) self.reply.bytesAvailable()
0
(Pdb) self.reply.read(1000)
b''
(Pdb) self.reply.read(1000)
b''
(Pdb) self.reply.read(1000)
b''
(Pdb) self.reply.read(1000)
b''
(Pdb) self.reply.read(1000)
b''
(Pdb) self.reply.close()
got reply error! NetworkError.OperationCanceledError
download progress! received=0 total=0
manager finished!
QIODevice::read (QNetworkReplyHttpImpl): device not open
reply finished! b''

and after i manually close reply it says, that device is not open and emits all the signals i want it to emit

i also made up an http server, which sends similar headers and empty content and it magically works! (but with this "manual close" it has some different output:

self.reply.isOpen()=True
got reply error! NetworkError.OperationCanceledError
download progress! received=0 total=0
manager finished!
QIODevice::read (QNetworkReplyHttpImpl): device not open
reply finished! b''
QNetworkReplyImplPrivate::error: Internal problem, this method must only be called once.

i have no ideas. think i probably should give up and create workarounds

SGaist

@xueqli before working around, please open a ticket on the bug report system with your findings. It seems you have a valid case to make.

xueqli

i found out that apparently it has nothing to do with either contents or headers,
and the real reason is: the request was using HTTP/2 protocol
disabling HTTP/2 (request.setAttribute(request.Attribute.Http2AllowedAttribute, False)) solves my problem

but what's wrong with HTTP/2 is yet to be figured out

SGaist

@xueqli Nice catch !

I would still recommend opening a ticket.

xueqli

@SGaist yea, i did: https://bugreports.qt.io/browse/QTBUG-123891
(and turned out both HTTP/2 and www-authenticate headers are required to reproduce this)

SGaist

Thanks for the link and thorough spelunking !

Since you have a Python reproducer, you should add it to the bug report, it will make things easier for developers to reproduce :-)