XSLT Transformation Pipeline - Content Management

XSLT Transformation Pipeline

Kaltura supports two XSLT mechanisms for transforming metadata XML automatically.

Profile-Level XSLT (Auto-Applied)

Attach an XSLT to a profile so it auto-transforms every metadata.add and metadata.update:

curl -X POST "$KALTURA_SERVICE_URL/service/metadata_metadataProfile/action/updateTransformationFromFile" \
  -d "ks=$KALTURA_KS" \
  -d "format=1" \
  -d "id=$PROFILE_ID" \
  -F "xsltFile=@transform.xslt"

Parameter	Type	Required	Description
id	integer	Yes	Profile ID to attach the XSLT to
xsltFile	file	Yes	XSLT stylesheet file (multipart form field)

How it works:

1. Attach XSLT via metadataProfile.updateTransformationFromFile
2. On every metadata.add and metadata.update, the server transforms incoming XML using the XSLT before validation
3. The XSLT receives KALTURA_CURRENT_TIMESTAMP (Unix timestamp) as a parameter
4. Transformed XML is validated against the XSD, then saved
5. If the transformation produces invalid output: XSLT_VALIDATION_ERROR

Example XSLT — auto-set a LastModified timestamp on every update:

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
  <xsl:param name="KALTURA_CURRENT_TIMESTAMP"/>
  <xsl:template match="@*|node()">
    <xsl:copy><xsl:apply-templates select="@*|node()"/></xsl:copy>
  </xsl:template>
  <xsl:template match="metadata/LastModified">
    <LastModified><xsl:value-of select="$KALTURA_CURRENT_TIMESTAMP"/></LastModified>
  </xsl:template>
</xsl:stylesheet>

One-Time XSLT Update

Transform existing metadata XML using a one-time XSLT via metadata.updateFromXSL (see section 6.10). The server reads the current XML, applies the XSLT, validates, and saves. Uses locking for concurrency safety.

Scheduled Task XSLT

Automated XSLT transforms via KalturaExecuteMetadataXsltObjectTask scheduled tasks. Enables periodic normalization, field migration, and computed field updates across all metadata instances matching a filter.