Extend metha-cat to extract metadata records

[Jakob Voß]

meta-cat should allow to extract harvested metadata records without OAI-Envelope (that's oai:record/oai:metadata/*).

[Martin Czygan]

Just curious, is that something documented in the spec?

Another question: aren't there XML tools that would allow specific XML tag extraction? That way, we could keep functionality separate.

[Jakob Voß]

As far as I understand the spec, oai:metadata is nested in oai:OAI-PMH/oai:ListRecords/oai:record and it may contain any XML elements.

<complexType name="metadataType">
  <annotation>
    <documentation>Metadata must be expressed in XML that complies
     with another XML Schema (namespace=#other). Metadata must be 
      explicitly qualified in the response.</documentation>
  </annotation>
  <sequence>
    <any namespace="##other" processContents="strict"/>
  </sequence>
</complexType>

I'm only interested in this child element(s) of oia:metadata because this is the actual payload. I'm surprised people keep the OAI envelope.

Suire Workaround is to apply an XSLT to each record (when using find and xargs) or to the while set (when using meta-cat), but this is far from a one-liner:

<?xml version="1.0" encoding="UTF-8"?>
<!-- Extract OAI metadata records from OAI-PMH responses -->
<xsl:transform xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0"
    xmlns:oai="http://www.openarchives.org/OAI/2.0/" exclude-result-prefixes="oai">
  <xsl:strip-space elements="*"/>
  <xsl:output method="xml" indent="yes"/>

  <xsl:template match="/Response">
    <records>
      <xsl:apply-templates select="ListRecords/oai:record"/>
    </records>
  </xsl:template>

  <xsl:template match="/Records">
    <records>
      <xsl:apply-templates select="oai:record"/>
    </records>
  </xsl:template>

  <xsl:template match="oai:record">
      <xsl:copy-of select="oai:metadata/*"/>
  </xsl:template>
</xsl:transform>  

I suppose the extraction would only be a few lines and an optional command line flag in metha source code.

[Martin Czygan]

I'm only interested in this child element(s) of oia:metadata because this is the actual payload. I'm surprised people keep the OAI envelope.I'm surprised people keep the OAI envelope.

Yes, metadata is the most interesting. If the envelop - oai:record/oai:metadata/* - would be just the metadata then one may mis the "set specifier" that's sometimes useful.

<record>
  <header status="">
    <identifier>oai:ojs.pkp.sfu.ca:article/2287</identifier>
    <datestamp>2020-06-22T11:34:53Z</datestamp>
    <setSpec>EJOEH:E</setSpec>
    <setSpec>driver</setSpec>
  </header>
  <metadata>
    <oai_dc:dc xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" ....oai_dc.xsd">
      <dc:title xml:lang="it-IT">Editoriale / Editorial</dc:title>
      <dc:creator>Szmigielski, S.</dc:creator>
      ...
    </oai_dc:dc>
  </metadata>
</record>

Thanks for the XSTL.

but this is far from a one-liner:

I appreciate the desire for one-liners.