Re: How do you ensure that data is not altered/corrupt

XSpec is a unit testing framework for and in XSLT. Its capabilities go far
beyond what schema validation was ever intended to do.

Roger, if you aren't using XSpec, you should be.

https://github.com/xspec/xspec/wiki

Regards, Wendell

On Fri, May 19, 2023 at 6:13b/AM Michael Kay mike@xxxxxxxxxxxx <
xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx> wrote:

> Testing, testing, testing. Plus tools to help prevent the mistakes arising
> in the first place.
>
> Schema validation can catch a lot of the errors, but it won't catch them
> all.
>
> We had a case like this where a customer was flagging up dangerous levels
> of some reading in medical reports by displaying the relevant figures in
> red. When they upgraded from XSLT 1.0 to 2.0, the test $level >
> $dangerLevel started doing a string comparison rather than a numeric
> comparison, with the effect that the red flags weren't appearing -- and it
> took them months to notice, because they weren't doing enough testing.
> Hopefully no-one died. Tests are the only answer: and because stylesheets
> can be thrown together quickly, people often neglect to follow good
> software engineering disciplines when changing them.
>
> Michael Kay
> Saxonica
>
> > On 19 May 2023, at 09:37, Roger L Costello costello@xxxxxxxxx <
> xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx> wrote:
> >
> > Hi Folks,
> >
> > In certain domains loss of life may occur if data is altered/corrupted
> in any way.
> >
> > Suppose you write an XSLT program which transforms this:
> >
> > <alt>12000 feet</alt>
> >
> > to this:
> >
> > <altitude>12000 feet</altitude>
> >
> > How do you ensure that the data -- 12000 feet -- was not
> altered/corrupted in the transformation?
> >
> > I have heard of people doing a hash on the data prior to the
> transformation, a hash on the data after the transformation, and then
> comparing the hashes. Is that what you would do when lives are on the line?
> What is your recommendation?
> >
> > /Roger
> >
> >
>
>
>

--
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