[x3d-public] [communications] X3D DOCTYPE problem

[Don Brutzman]

Thanks for further sleuthing Vince, very helpful.

- Recommend we apply limited modification to avoid Apache server redirects in specifications/ directory as you suggest.  That will minimize bogus failures to user agents.

- Have thought already that we should shift to https for X3D4, so another excellent suggestion.  Will look closely and examine further whether that is OK for X3D3.

- Still TODO: getting my account permissions restored will further help troubleshooting and comparison of solutions.

Meanwhile am happy to report that as a temporary workaround, X3D Validator will accept a scene using https address for DOCTYPE and schema.


On 9/12/2020 7:34 PM, vmarchetti at kshell.com wrote:
> 
> As observed at 10:20 PM EDT on 12 Sept 2020
> 
> A HTTP request to https://www.web3d.org/specifications/x3d-3.3.dtd made with the curl tool (on Mac OS) returns the 142k DTD file, appears well formed
> 
> The request to the http (unencrypted, discouraged by modern browsers) http://www.web3d.org/specifications/x3d-3.3.dtd returns a redirect HTTP response, with headers:
> 
> HTTP/1.1 302 Found
> Date: Sun, 13 Sep 2020 02:15:33 GMT
> Server: Apache
> X-Content-Type-Options: nosniff
> Location: https://www.web3d.org/specifications/x3d-3.3.dtd
> Cache-Control: max-age=1209600
> Expires: Sun, 27 Sep 2020 02:15:33 GMT
> Content-Length: 232
> Content-Type: text/html; charset=iso-8859-1
> 
> 
> and the body of the HTTP response is an HTML-markup version of this information, so not well formed DTD.
> 
> It appears that some of the validation tools will follow the redirect and some will not.
> 
> I do not know if the server configuration has been changed recently to redirect requests to URLS  in http://www.web3d.org/specifications/* space.
> 
> Request for our webpages i.e. http://www.web3d.org/ have been redirected for some time.
> 
> Solutions to this problem would be
> 
> -- allow server to directly server requests to http://www.web3d.org/specifications/* without redirection
> -- update or configure tools to follow HTTP 302 redirections
> 
> Vince Marchetti
> 
>> On Sep 12, 2020, at 7:55 PM, Don Brutzman <brutzman at nps.edu> wrote:
>>
>> We noticed an emergent problem with X3D Validator about a week ago and, with difficulty, have been trying to sleuth what the root cause might be.
>>
>> After multiple diagnostic efforts, we now think that the problem is on the web3d.org server, there is some issue within the DTD files themselves.  Unfortunately there is also a problem with my account which currently prevents troubleshooting further and (hopefully) fixing it.
>>
>> This problem has blocked proper DTD validation, which might in turn block validation of numerous tools loading/validating X3D models.  Have confirmed that some tools work (probably due to prior caching) and other tools fail. Example failure output:
>>
>>> check well-formedness
>>> http://www.web3d.org/specifications/x3d-3.3.dtd:1:3: The markup declarations contained or pointed to by the document type declaration must be well-formed.
>>> Could not validate document C:\x3d-code\www.web3d.org\x3d\content\examples\X3dForWebAuthors\HelloWorld.x3d: org.xml.sax.SAXParseExceptionpublicId: ISO//Web3D//DTD X3D 3.3//EN; systemId: http://www.web3d.org/specifications/x3d-3.3.dtd; lineNumber: 1; columnNumber: 3; The markup declarations contained or pointed to by the document type declaration must be well-formed.
>>> C:\x3d-code\www.web3d.org\x3d\content\examples\X3dForWebAuthors\HelloWorld.x3d is not a valid XML document
>>
>> Meanwhile XML Spy can validate the same model successfully.  It is both exceptionally strict and also added native X3D support a few months back.  So this approach confirms that X3D models we are testing remain unchanged and correct.
>>
>> Web3D Communications Team and webmaster have been notified about the access problem preventing further troubleshooting.
>>
>> The DOCTYPE problem does not appear to prevent successful X_ITE and X3DOM display of X3D models.
>>
>> * https://x3dgraphics.com/examples//X3dForWebAuthors/Chapter02GeometryPrimitives/BoxExampleX_ITE.html
>> * https://x3dgraphics.com/examples//X3dForWebAuthors/Chapter02GeometryPrimitives/BoxExampleX3dom.xhtml
>>
>> Once this is also sorted out, will post regarding resumption of capability.  Apologies for any difficulties this problem causes tool developers and scene modelers.


all the best, Don
-- 
Don Brutzman  Naval Postgraduate School, Code USW/Br       brutzman at nps.edu
Watkins 270,  MOVES Institute, Monterey CA 93943-5000 USA   +1.831.656.2149
X3D graphics, virtual worlds, navy robotics http://faculty.nps.edu/brutzman