[x3d-public] Fwd: ProtoInstance USE without name
John Carlson
yottzumm at gmail.com
Sat Nov 28 10:48:46 PST 2020
Christopher, I have no real control over XML to JSON, even though I have a
little used tool which does it.
My primary goal is rendering JSON as other “encodings.”
So if something doesn’t match my schema, it gets flagged. If we allow
name along with USE, that means I have to put special-case code in my
schema generating tool. My goal is to stop bad JSON at its source, namely
X3dToJson.xslt.
In other words, I don’t want to write schema that won’t appear in the
standard (TBD).
It is much easier for humans to understand consistent rules, and not a
bunch of if statements testing for whether I’m dealing with a ProtoInstance
and therefore I need to do something different.
Let’s make one rule and apply it to all instances of name and USE in a node.
John
On Sat, Nov 28, 2020 at 12:31 PM Christoph Valentin <
christoph.valentin at gmx.at> wrote:
> hi John.
>
> Understand.
>
> All I can remember, when I did my trials with x3d, then some players
> insisted on the "name" attribute, others considered it an error, at least a
> warning.
>
> Using <Script> was a compromise that just worked.
>
> So lets wait the test results, before defining the behavior of relay
> software between XML and JSON (which should be applicable to ALL browsers
> and users).
>
> I do not know if I'm the only one who used the <Script>- Woraround.
>
> kr
>
> --
> Diese Nachricht wurde von meinem Android Mobiltelefon mit GMX Mail
> gesendet.
> Am 28.11.20, 19:09 schrieb John Carlson <yottzumm at gmail.com>:
>
>> I don’t see JSON schema moving through IETF quickly, and last I heard,
>> they were going to standardize 4 different drafts of JSON schema. They
>> are even seeking assistance when taking the draft to IETF. Volunteers?
>>
>> X3D does not have a standardized JSON schema. The best we have for USE
>> might work across all versions of X3D. I do not know the history of USE.
>>
>> It is my intention to maintain a JSON schema for each X3DUOM versions.
>>
>> I don’t think we’re putting validation in the standard, that’s up to the
>> vendors.
>>
>> I don’t ever recall seeing X3D XML schema in a standard?
>>
>> John
>>
>> On Sat, Nov 28, 2020 at 11:52 AM Christoph Valentin <
>> christoph.valentin at gmx.at> wrote:
>>
>>> Hi John,
>>>
>>> as far as I think to understand the IETF community, the robustness
>>> principle is meant to be applied for cases, when the standard is fuzzy.
>>>
>>> So it applies to our case here.
>>>
>>> You can do a very strict validation, if a standard
>>>
>>> - is well-defined, well-accepted, well-deployed and precise
>>> - is not subject to future changes nor has got a past
>>>
>>> Otherwise every validation must accept compromises
>>>
>>> Agree?
>>>
>>> KR
>>> Christoph
>>>
>>>
>>> *Gesendet:* Samstag, 28. November 2020 um 18:36 Uhr
>>> *Von:* "John Carlson" <yottzumm at gmail.com>
>>> *An:* "Christoph Valentin" <christoph.valentin at gmx.at>
>>> *Cc:* "X3D Graphics public mailing list" <x3d-public at web3d.org>
>>> *Betreff:* Re: [x3d-public] Fwd: ProtoInstance USE without name
>>> Should one accept SQL injection? No!
>>>
>>> Note: I have not added any validation to X3DOM or X_ITE, and do not
>>> expect to.
>>>
>>> I do not expect to strip out validation from X3DJSONLD anytime soon.
>>>
>>> John
>>>
>>> On Sat, Nov 28, 2020 at 11:26 AM John Carlson <yottzumm at gmail.com>
>>> wrote:
>>>
>>>> If I accept everything, validation is useless. That’s why I provide a
>>>> way for the user to override :).
>>>>
>>>> On Sat, Nov 28, 2020 at 11:22 AM Christoph Valentin <
>>>> christoph.valentin at gmx.at> wrote:
>>>>
>>>>> hi all
>>>>>
>>>>> Do you know Jon Postel's robustness principle?
>>>>>
>>>>> Be liberal in what you accept and conservative in what you send out.
>>>>>
>>>>> means: add the name attribute when sending
>>>>> keep the name attribute when forwarding/proxying
>>>>> ignore the name attribute when receiving.
>>>>> kr
>>>>>
>>>>> --
>>>>> Diese Nachricht wurde von meinem Android Mobiltelefon mit GMX Mail
>>>>> gesendet.
>>>>> Am 28.11.20, 17:58 schrieb John Carlson <yottzumm at gmail.com>:
>>>>>
>>>>>> Again, if USE is specified in a proto instance in X3D JSON, then
>>>>>> X3DJSONLD and related tools will not validate a name property in the node.
>>>>>> I suggest X3dToJson.xslt reject the spurious name when generating JSON.
>>>>>>
>>>>>> John
>>>>>>
>>>>>> ---------- Forwarded message ---------
>>>>>> From: Christoph Valentin <christoph.valentin at gmx.at>
>>>>>> Date: Sat, Nov 28, 2020 at 8:18 AM
>>>>>> Subject: Re: [x3d-public] ProtoInstance USE without name
>>>>>> To: Andreas Plesch <andreasplesch at gmail.com>
>>>>>> CC: X3D Graphics public mailing list <x3d-public at web3d.org>
>>>>>>
>>>>>> Hi Andreas,
>>>>>>
>>>>>> I felt free to provide an example scene in three flavors.
>>>>>>
>>>>>> The prototype renders a little pig that says "Eatme!", when you touch
>>>>>> it (in remembrance of Douglas Adams)
>>>>>>
>>>>>> Version A: <ProtoInstance USE="xxx" name="yyy"/> WITH name
>>>>>> attribute - standards compliant
>>>>>> Version B: <ProtoInstance USE="xxx"/> WITHOUT name attribute
>>>>>> Version C: <Script USE="xxx"/> WORKAROUND - works for all browsers
>>>>>>
>>>>>> I tested with BS Contact --- he can cope with all three versions.
>>>>>>
>>>>>> Download the .zip file at
>>>>>> https://lc-soc-lc.at/experimental/ProtoInstanceWithUSE/ I
>>>>>> provide it by a GPLv3.
>>>>>>
>>>>>> Feed Back welcome. You may take it and give it to your benchmark
>>>>>> tests, if you like.
>>>>>>
>>>>>> Kind regards,
>>>>>> Christoph
>>>>>>
>>>>>>
>>>>>> *Gesendet:* Dienstag, 24. November 2020 um 00:30 Uhr
>>>>>> *Von:* "Andreas Plesch" <andreasplesch at gmail.com>
>>>>>> *An:* "Christoph Valentin" <christoph.valentin at gmx.at>
>>>>>> *Cc:* "X3D Graphics public mailing list" <x3d-public at web3d.org>
>>>>>> *Betreff:* Re: [x3d-public] ProtoInstance USE without name
>>>>>> Hi Christoph,
>>>>>>
>>>>>> thanks, interesting. Perhaps it will be useful to try a USE
>>>>>> ProtoInstance in a very simple scene, in multiple browsers.
>>>>>>
>>>>>> -Andreas
>>>>>>
>>>>>> On Mon, Nov 23, 2020 at 1:01 PM Christoph Valentin <
>>>>>> christoph.valentin at gmx.at> wrote:
>>>>>>
>>>>>>>
>>>>>>> Hi
>>>>>>>
>>>>>>> This bug is common to many X3D players (even classical non-WebGL X3D
>>>>>>> players).
>>>>>>>
>>>>>>> I was used to use following workaround, which worked for all
>>>>>>> relevant players:
>>>>>>>
>>>>>>> If I want to USE a DEFd ProtoInstance, I will actually instantiate a
>>>>>>> <Script> node with USE.
>>>>>>>
>>>>>>> KR,
>>>>>>> Christoph
>>>>>>>
>>>>>>> *Gesendet:* Montag, 23. November 2020 um 00:00 Uhr
>>>>>>> *Von:* "Andreas Plesch" <andreasplesch at gmail.com>
>>>>>>> *An:* "X3D Graphics public mailing list" <x3d-public at web3d.org>
>>>>>>> *Betreff:* [x3d-public] ProtoInstance USE without name
>>>>>>> Looking at why the old Prototypes for HAnim did not work properly
>>>>>>> for x3dom, I found that the xml examples typically have a ProtoInstance
>>>>>>> statement with a USE attribute but without the corresponding name attribute
>>>>>>> defining the actual node type. However, x3dom expects a name attribute with
>>>>>>> every ProtoInstance statement, even USE ones, to be able to insert the
>>>>>>> appropriate node.
>>>>>>>
>>>>>>> The xml spec at
>>>>>>>
>>>>>>>
>>>>>>> https://www.web3d.org/documents/specifications/19776-1/V3.3/Part01/concepts.html#ProtoInstanceAndFieldValueStatement
>>>>>>>
>>>>>>> does not address USE of ProtoInstances but all examples always have
>>>>>>> a name attribute.
>>>>>>>
>>>>>>> Also, in my quite extensive testing of Protos, I did not come across
>>>>>>> other examples of ProtoInstance elements without a name attribute.
>>>>>>>
>>>>>>> To be fair, the name attribute is not strictly necessary for USE
>>>>>>> ProtoInstances since the type of the inserted node can be determined from
>>>>>>> the referenced DEF node. But having the name attribute makes ProtoInstance
>>>>>>> elements more similar to regular nodes. So I think not requiring the name
>>>>>>> attribute for USE ProtoInstances should be explicitly allowed in the xml
>>>>>>> spec., but still be encouraged.
>>>>>>>
>>>>>>> I do not think the xml spec. would be otherwise affected by V.4 ?
>>>>>>>
>>>>>>> Best, Andreas
>>>>>>>
>>>>>>>
>>>>>> --
>>>>>>> Andreas Plesch
>>>>>>> Waltham, MA 02453
>>>>>>> _______________________________________________ x3d-public mailing
>>>>>>> list x3d-public at web3d.org
>>>>>>> http://web3d.org/mailman/listinfo/x3d-public_web3d.org
>>>>>>>
>>>>>>
>>>>>>
>>>>>> --
>>>>>> Andreas Plesch
>>>>>> Waltham, MA 02453
>>>>>> _______________________________________________
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>>>>>> _______________________________________________ x3d-public mailing
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>>>>>
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