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documentPool and textResourcePool for SaxonJS.XPath.evaluate?

Added by Martin Honnen 11 months ago

For SaxonJS 2.5, the documentation for the transform function in https://www.saxonica.com/saxon-js/documentation2/index.html#!api/transform shows two options documentPool and textResourcePool that can be used together with SaxonJS.getResource to ensure doc or unparsed-text calls access preloaded resources, allowing some kind of URI resolution.

Now I wonder whether the same exists for SaxonJS.XPath.evaluate: I have looked into loading the files in a Github Gist, using the asynchronous API that Github provides and that gives me a files object of e.g. { "foo.xml" : { "content" : "<root>...</root>", "language": "XML", "type": "application/xml", "filename" : "foo.xml" }, "bar.xml" : { "content" : "<root>...</root>", "language": "XML", "type": "application/xml", "filename" : "bar.xml" } }, now I would like my XPath (or XSLT code code called using fn:transform) evaluated by SaxonJS.XPath.evaluate to not to try to load e.g. foo.xml over HTTP with doc('foo.xml') but access it from a documentPool I set up from the Github Gist files result.

Is anything like that possible in SaxonJS 2.5 for SaxonJS.XPath.evaluate?

If not, is that planned for 3.0?


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RE: documentPool and textResourcePool for SaxonJS.XPath.evaluate? - Added by Martin Honnen 11 months ago

Everyone on vacation these days?

My suspicion is that SaxonJS 3 will give me some API to compile XSLT to SEF and then run that compiled SEF within the same Javascript program, so perhaps then I can just use the transform function and documentPool and/or textResourcePool. If I ever manage to understand the various options the getResource function has; the documentation https://www.saxonica.com/saxon-js/documentation2/index.html#!api/getResource say " Exactly one of location, file, or text must be supplied" but also baseURI property on the options "Absolute base URI for the resource. The base URI of the resource is automatically set when obtained using location or file. This option can be used to set the base URI for a resource supplied using text.".

Where is the base URI used or stored in the context of the Promise getResource returns?

RE: documentPool and textResourcePool for SaxonJS.XPath.evaluate? - Added by Martin Honnen 11 months ago

Still have no idea what the baseURI is meant for or where it is used or stored in the context of passing text to getResource but for SaxonJS.transform I finally got some documentPool and textResourcePool working to not make a request to a file or http URL but to use my string/text resource, both within the browser and with Node.js.

The key seems to be to store the absolute URL as the key in the Javascript object.

Still have no idea how to use that approach with SaxonJS.XPath.evaluate.

RE: documentPool and textResourcePool for SaxonJS.XPath.evaluate? - Added by Norm Tovey-Walsh 11 months ago

Everyone on vacation these days?

No. Sorry. Just … busy. I’ll try to look into this today, or early next week.

Be seeing you,
norm

--
Norm Tovey-Walsh
Saxonica

RE: documentPool and textResourcePool for SaxonJS.XPath.evaluate? - Added by Martin Honnen 11 months ago

Based on some tests it seems the only place where a documentPool and/or a textResourcePool can be provided is SaxonJS.transform.

Now after some pondering I thought I could just write a custom stylesheet that exposes fn:transform in a public stylesheet function and then pass that SEF compiled stylesheet together with the wanted parameters in and would have a way to use a documentPool and evaluate XSLT on the fly.

My simplest test case seems to fail, however, with SaxonJS 2.5 under Node.js with e.g.

Transformation failure: Error FODC0002 at exposeFnTransform.xsl#8
  Cannot read file file:///C:/Users/marti/OneDrive/Documents/xslt/saxonjs-documentPool/doc1.xml - ENOENT: no such file or directory, open 'C:\Users\marti\OneDrive\Documents\xslt\saxonjs-documentPool\doc1.xml'

node:internal/process/promises:288
            triggerUncaughtException(err, true /* fromPromise */);
            ^
Error
    at new L (C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4109:549)
    at Object.readFile (C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4713:171)
    at Object.readFile (C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4108:74)
    at C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4340:316
    at a (C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4338:294)
    at Object.Ec (C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4340:280)
    at doc (C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4513:298)
    at C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4632:444
    at Object.push (C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4390:245)
    at Object.e [as internalTransform] (C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4988:69)
    at transform (C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4578:303)
    at C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4632:444
    at C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4625:263
    at B (C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4614:164)
    at C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4614:412
    at C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4627:186
    at C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4618:382
    at C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4670:281
    at C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4618:382
    at A (C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4600:78)
    at C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4672:459
    at C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4646:463
    at C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4618:382
    at C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4670:281
    at C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4618:382
    at Object.push (C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4390:245)
    at e (C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:4987:320)
    at C:\Users\marti\AppData\Roaming\npm\node_modules\saxon-js\SaxonJS2N.js:5015:342 {
  message: "Cannot read file file:///C:/Users/marti/OneDrive/Documents/xslt/saxonjs-documentPool/doc1.xml - ENOENT: no such file or directory, open 'C:\\Users\\marti\\OneDrive\\Documents\\xslt\\saxonjs-documentPool\\doc1.xml'",
  name: 'XError',
  code: 'FODC0002',
  xsltLineNr: '8',
  xsltModule: 'exposeFnTransform.xsl'
}

although the documentPool I have set up has e.g.

{
  'file:///C:/Users/marti/OneDrive/Documents/xslt/saxonjs-documentPool/doc1.xml': <ref *1> Hf {

I guess I need to file that as a bug (or lack of feature).

    (1-4/4)

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