QNetworkReply reply 301 issue

victor wang

Hi, i'm using Qt5.5 on my computer.
When i clicked the button then will do the request.
This is my code here

It will do the SLOT thing.
Get into replyFinished(), code is here

When i print the qDebug out, it shows 301.
I went to search the information and i saw one of the information here(please search 301)

How can i fix this one?

jsulm

@victor-wang
There is nothing to fix.
See here: https://en.wikipedia.org/wiki/HTTP_301
It means the URL you're trying to access has moved.
The new URL should be in the reply.
Just try another URL like https://www.qt.io/developers

Paul Colby

Also consider using QNetworkRequest::FollowRedirectsAttribute, if that suits your need :)

Cheers.

victor wang

@jsulm
Did you mean i have to change the website like this ?

manager->get(QNetworkRequest(QUrl("https://www.qt.io/developers")));

jsulm

@victor-wang You can, or do what @Paul-Colby suggested.

victor wang

@jsulm
It's not wok.
It still will print 301 out.
@Paul-Colby
I will try it.

jsulm

@victor-wang It should work. Did you rebuild?

victor wang

@jsulm
Yes, i had rebuild it.

But QNetworkReply::NetworkError still print 301 out to me.

The information said if you receive 301 it means "the Network Access API cannot honor the request because the protocol is not known" .

@Paul-Colby
Why i can't find FollowRedirectsAttribute on my Qt?

jsulm

@victor-wang FollowRedirectsAttribute was introduced in Qt 5.6. Which Qt version do you use?

victor wang

@jsulm
Yes, i had rebuild it.

But QNetworkReply::NetworkError still print 301 out to me.

The information said if you receive 301 it means "the Network Access API cannot honor the request because the protocol is not known" .

I'm using Qt5.5 that's why i can't using it.

jsulm

@victor-wang Please read the link I provided. 301 means:
"The HTTP response status code 301 Moved Permanently is used for permanent URL redirection" - it is not related to protocol.

jsulm

@victor-wang You will need to handle redirections (301) by yourself: the new URL should be in the response (see the link I posted):

HTTP/1.1 301 Moved Permanently
Location: http://www.example.org/index.asp

"Location" contains the new URL.

victor wang

@jsulm
I'm using "http://www.example.org/index.asp"
But i get the error 404.
Why is that happened?

jsulm

@victor-wang Can you access this URL using a web browser on the same machine?
Did you enter the URL correctly in your code?

victor wang

@jsulm
I can't ping anything on "Location".
There is an error here

And i"m sure that i had write the write URL in my code.
But i will get the error 404.

Besides, i've try the other URL which is the test URL gave from my company.
And i got the error 0!

What should i do ?

jsulm

@victor-wang Interesting: I can access that URL in a browser but ping does not work.
Maybe there is something with out network? Do you have a proxy? Firewall?

victor wang

@jsulm
I had find the solution.
Qt cannot recognize the title "www1.winmate" but recognize the IP address for instead.
I changed it into ip address and it worked!

Hendrik Vennekate

@jsulm I think you are misreading the question: this is not about HTTP status 301 (which would indeed be a redirect), but about the QNetworkReply::NetworkError enum, where 301 means "the Network Access API cannot honor the request because the protocol is not known". I'm currently struggling with a similar issue with a particular Qt build where this pops up for HTTPS (HTTP itself is fine, so I'm guessing I didn't do the SSL dependencies right...)