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RE: Source of HTTP Content-Language header

From: Widmer, Christoph <Christoph.Widmer@sonova.com>
Date: Mon, 5 Jun 2017 18:58:35 +0000
To: "Jukka K. Korpela" <jukkakk@gmail.com>
CC: "www-validator@w3.org" <www-validator@w3.org>
Message-ID: <9CC1F42D98512745A73182680F8EFB24017E96B3CB@CH01SW0722.corp.ads>
Hello Jukka,

Thank you for your input.

>> using an online HTTP header viewer like http://www.rexswain.com/httpview.html

What I don't understand is why this warning appears for some of our pages, but not for others. There is no warning for instance for www.f3historic.com/calendar.php<http://www.f3historic.com/calendar.php> yet the validator shows a warning for www.f3historic.com/calendar.php<http://www.f3historic.com/calendar.php> but both show the same information regarding content language (fr) in the HTTP header and language in the HTML start tag (en) when I look at them in www.rexswain.com/httpview.html<http://www.rexswain.com/httpview.html>. So, this warning appears to be inconsistent or an outright bug in the validator.

Best regards, Christoph

From: Jukka K. Korpela [mailto:jukkakk@gmail.com]
Sent: Montag, 5. Juni 2017 18:32
To: Widmer, Christoph
Cc: www-validator@w3.org
Subject: Re: Source of HTTP Content-Language header

On Mon, Jun 5, 2017 at 1:23 PM, Widmer, Christoph <Christoph.Widmer@sonova.com<mailto:Christoph.Widmer@sonova.com>> wrote:

The W3 Validator reports a content language warning for my www.f3historic.com<http://www.f3historic.com> website. It says that

The value of the HTTP Content-Language header is "fr" but it will be ignored because the html start tag has lang="en".

It is a warning only, since the conflict is resolved by the specifications. In principle, however, programs might use the Content-Language header value when dealing with the docuement as a whole. So it is useful that the problem is pointed out-

I checked all files and couldn't find any reference to the content language header being set to French. Could you please modify the W3 Validator such that it shows the location of the content language header, just like it does for the HTML start tag.

It is nowhere in the HTML document. It is in HTTP headers that accompany it and are sent according to some logic. This cannot be studied from outside, only “inside” the server. We can just see the headers sent. They can be inspected using various debugging tools in browsers or, perhaps best for casual use, using an online HTTP header viewer like http://www.rexswain.com/httpview.html

Perhaps the validator should echo the HTTP response headers, at least if an option for that is selected. However, there’s a risk in adding the amount of output. And if you had to check an option to get the headers, the odds are that users who would need them would not find it and understand it.


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Received on Monday, 5 June 2017 19:05:35 UTC

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