detectWeb did not match

Roalderik · November 18, 2015

Hi

I'm trying to build a translator for www.retsinformation.dk (an official site with all Danish legislation). This is my first go at writing a translator, so I'm going through https://www.zotero.org/support/dev/how_to_write_a_zotero_translator_plusplus. However, it starts to get complicated in ch. 11, and I can't get example 11.6 to work.

I've copy-pasted the following snippet from the guide into Scaffold:

function detectWeb(doc, url) {
var namespace = doc.documentElement.namespaceURI;
var nsResolver = namespace ? function(prefix) {
if (prefix == "x" ) return namespace; else return null;
} : null;
var myXPath = '//td[1]';
var myXPathObject =
doc.evaluate(myXPath, doc, nsResolver, XPathResult.ANY_TYPE, null).iterateNext().textContent;
Zotero.debug(myXPathObject);
}

and the result I get is "detectWeb did not match". What's going wrong?

adamsmith · November 18, 2015

You would get a does not match message with this, that's correct (in technical terms, it's a function that doesn't return anything). Are you not getting the debug output (i.e. the content of //td[1]) displayed before it?

note that there are simpler ways of doing a lot of this now. You may actually be better off looking at some of the documentation at
https://www.zotero.org/support/dev/translators/coding
Specifically, for almost all purposes you can replace doc.evaluate and the whole namespace mess with the the much simpler
ZU.xpath() and ZU.xpathText(). In your example, e.g.

function detectWeb(doc, url){
  var myXPath = '//td[1]';
  var myXPathText = ZU.xpathText(doc, myXPath);
  Z.debug(myXPathText);
}

Roalderik · November 19, 2015

Thanks for the answer.

I did indeed get the debug output first - somehow I managed to overlook that.

Thank for the link too, that will certainly be useful for me.