alt Hacker NewsI have worked for a company that (probably still is) heavily invested in XSLT for XML templating. It's not good, and they would probably migrate from it if they could.
1. Even though there are newer XSLT standards, XSLT 1.0 is still dominant. It is quite limited and weird compared to the newer standards.
2. Resolving performance problems of XSLT templates is hell. XSLT is a Turing-complete functional-style language, with performance very much abstracted away. There are XSLT templates that worked fine for most documents, but then one document came in with a ~100 row table and it blew up. Turns out that the template that processed the table is O(N^2) or worse, without any obvious way to optimize it (it might even have an XPath on each row that itself is O(N) or worse). I don't exactly know how it manifested, but as I recall the document was processed by XSLT for more than 7 minutes.
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It's generally speaking part of the problem with the entire "XML as a savior" mindset of that earlier era and a big reason of why we left them, doesn't matter if XSLT or SOAP or even XHTML in a way ... Those were defined as machine language meant for machine talking to machine, and invariably something go south and it's not really made for us to intervene in the middle; it can be done but it's way more work than it should be; especially since they clearly never based it on the idea that those machine will sometime speak "wrong", or a different "dialect".
It looks great, then you design your stuff and it goes great, then you deploy to the real world and everything catches on fire instantly and everytime you stop one another one starts.
It's odd cause xslt was clearly made in an era where expecting long source xml to be processed was the norm, and nested loops would blow up obviously..
> XSLT 1.0 is still dominant
How, where? In 2013 I was still working a lot with XSLT and 1.0 was completely dead everywhere one looked. Saxon was free for XSLT 2 and was excellent.
I used to do transformation of both huge documents, and large number of small documents, with zero performance problems.
Are you using the commercial version of Saxon? It's not expensive, and IMHO worth it for the features it supports (including the newer standards) and the performance. If I remember correctly (it was a long time ago) it does some clever optimizations.
From my experience, most simple websites are fine with XSLT 1.0 and don't experience any performance problems.
Same here.
A couple of blue chip websites I‘ve seen that could be completely taken down just by requesting the sitemap (more than once per minute).
PS: That being said it is an implantation issue. But it may speak for itself that 100% of the XSLT projects I‘ve seen had it.
XSLT/XPath have evolved since XSLT 1.0.
Features are now available like key (index) to greatly speedup the processing. Good XSLT implementation like Saxon definitively helps as well on the perf aspect.
When it comes to transform XML to something else, XSLT is quite handy by structuring the logic.