xsl-list
[Top] [All Lists]

Re: [xsl] Random UUID in pure XSLT?

2020-11-11 14:35:13
Hi Wendell,

Dimitre, suggesting the web service option, offers

for $i in 1 to $N
   return  unparsed-text("https://uuidgen.org/api/v/4";)

I'll try this ... but what prevents an XSLT engine giving me the same
result each time? (Oh I see.)

Dr. Kay suggested a fix that will block the deterministic-compliance
attempts of a hypothetical XPath 3.0+ (or XSLT 2.0) implementation;

for $i in 1 to 100
  return unparsed-text(concat("https://uuidgen.org/api/v/4?x=";, $i))


I say "hypothetical" above, because even Saxon (the 9.9.1.7 versions used
in Oxygen) is non-compliant and produces all-different results for this
transformation:

<xsl:stylesheet version="3.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform";>
  <xsl:output method="text"/>

  <xsl:template match="/">
    <xsl:sequence select=
      "for $i in 1 to 100
         return unparsed-text('https://uuidgen.org/api/v/4')"/>

  </xsl:template></xsl:stylesheet>


Interestingly, I have an old version: Saxon 9.1.01, which is compliant to
the XSLT 2.0 specification and needs the URL-tail addition in order to get
its determinism bypassed.

HTH, Dimitre


On Wed, Nov 11, 2020 at 12:19 PM Wendell Piez wapiez(_at_)wendellpiez(_dot_)com 
<
xsl-list-service(_at_)lists(_dot_)mulberrytech(_dot_)com> wrote:

Hi,

Dimitre, suggesting the web service option, offers

for $i in 1 to $N
   return  unparsed-text("https://uuidgen.org/api/v/4";)

I'll try this ... but what prevents an XSLT engine giving me the same
result each time? (Oh I see.)

Update since yesterday -- I've had some apparent success coding up an
implementation of UUID v4 using fn:random-number-generator() ... results so
far are here (comments welcome):


https://github.com/wendellpiez/oscal-tools/blob/issue10-uuid-util/xslt/uuid/random-util.xsl

The functions are deterministic -- they return the same UUID (or UUID
sequence of specified length) for the same seed. In my application, this is
actually a feature.

Thanks for all the info and help so far this is great!

Cheers, Wendell

On Wed, Nov 11, 2020 at 1:32 PM Dimitre Novatchev 
dnovatchev(_at_)gmail(_dot_)com <
xsl-list-service(_at_)lists(_dot_)mulberrytech(_dot_)com> wrote:

 how can I go about producing random UUIDs, in dozens or hundreds,
inside an XSLT pipeline, without extension functions in Saxon.

This is actually very easy and doesn't require the use of any extension
functions:

*unparsed-text("https://uuidgen.org/api/v/4
<https://uuidgen.org/api/v/4>")*

or if you need N of them:

*for $i in 1 to $N*
*   return  unparsed-text("https://uuidgen.org/api/v/4
<https://uuidgen.org/api/v/4>") *



😆

HTH, Dimitre

On Tue, Nov 10, 2020 at 8:36 AM Piez, Wendell A. (Fed)
wendell(_dot_)piez(_at_)nist(_dot_)gov 
<xsl-list-service(_at_)lists(_dot_)mulberrytech(_dot_)com> wrote:

XSL Friends –



Today I write from the day job, where I am researching the question of
how can I go about producing random UUIDs, in dozens or hundreds, inside an
XSLT pipeline, without extension functions in Saxon. The Java randomUUID()
function works nicely when it’s available, but I need to distribute the
capability for SaxonHE and eventually SaxonJS.



We do not have an available implementation of RFC 4122 v4 “random UUID”
in pure XSLT do we, free to use (and study)? I know the functional nature
of the language makes randomness, um, problematic (when isn’t it?), which
sometimes means workarounds – that’s all fine. Indeed so would calling out
to a web service if it is known to be reliable. I have thought about
handing a list of UUIDs in at runtime, but as I said, there may sometimes
be hundreds and perhaps thousands, which makes that approach seem a bit
scary.



Any thoughts or perspective would be most welcome.



Thanks, Wendell






XSL-List info and archive <http://www.mulberrytech.com/xsl/xsl-list>
EasyUnsubscribe <http://lists.mulberrytech.com/unsub/xsl-list/782854> (by
email)



--
Cheers,
Dimitre Novatchev
---------------------------------------
Truly great madness cannot be achieved without significant intelligence.
---------------------------------------
To invent, you need a good imagination and a pile of junk
-------------------------------------
Never fight an inanimate object
-------------------------------------
To avoid situations in which you might make mistakes may be the
biggest mistake of all
------------------------------------
Quality means doing it right when no one is looking.
-------------------------------------
You've achieved success in your field when you don't know whether what
you're doing is work or play
-------------------------------------
To achieve the impossible dream, try going to sleep.
-------------------------------------
Facts do not cease to exist because they are ignored.
-------------------------------------
Typing monkeys will write all Shakespeare's works in 200yrs.Will they
write all patents, too? :)
-------------------------------------
Sanity is madness put to good use.
-------------------------------------
I finally figured out the only reason to be alive is to enjoy it.

XSL-List info and archive <http://www.mulberrytech.com/xsl/xsl-list>
EasyUnsubscribe <http://lists.mulberrytech.com/unsub/xsl-list/174322> (by
email)



--
...Wendell Piez... ...wendell -at- nist -dot- gov...
...wendellpiez.com... ...pellucidliterature.org... ...pausepress.org...
...github.com/wendellpiez... ...gitlab.coko.foundation/wendell...
XSL-List info and archive <http://www.mulberrytech.com/xsl/xsl-list>
EasyUnsubscribe <http://lists.mulberrytech.com/unsub/xsl-list/782854> (by
email <>)



-- 
Cheers,
Dimitre Novatchev
---------------------------------------
Truly great madness cannot be achieved without significant intelligence.
---------------------------------------
To invent, you need a good imagination and a pile of junk
-------------------------------------
Never fight an inanimate object
-------------------------------------
To avoid situations in which you might make mistakes may be the
biggest mistake of all
------------------------------------
Quality means doing it right when no one is looking.
-------------------------------------
You've achieved success in your field when you don't know whether what
you're doing is work or play
-------------------------------------
To achieve the impossible dream, try going to sleep.
-------------------------------------
Facts do not cease to exist because they are ignored.
-------------------------------------
Typing monkeys will write all Shakespeare's works in 200yrs.Will they write
all patents, too? :)
-------------------------------------
Sanity is madness put to good use.
-------------------------------------
I finally figured out the only reason to be alive is to enjoy it.
--~----------------------------------------------------------------
XSL-List info and archive: http://www.mulberrytech.com/xsl/xsl-list
EasyUnsubscribe: http://lists.mulberrytech.com/unsub/xsl-list/1167547
or by email: xsl-list-unsub(_at_)lists(_dot_)mulberrytech(_dot_)com
--~--
<Prev in Thread] Current Thread [Next in Thread>