XSLT

XSLT and XPath are two key technologies used within Sahana Eden to allow easy importing and exporting of information in a wide variety of formats.

Support for importing and exporting data is mostly managed via XSLT templates.

Sahana Data Models

The underlying data models in models/ define the resulting structure that will be within the XML.

Sahana XML Representation

See: S3XRC/S3XML

There are 2 parameters which are passed in:

• name (comes from the resourcename - e.g. 'shelter')
• xsltmode (passed in as a var on the URL - e.g. '&xsltmode=extended')

A collection of useful reusable functions are stored in static/formats/xml/commons.xsl

Exporting Data from Sahana

Sahana export templates are stored in: static/formats/*/export.xsl

Importing Data from Sahana

Sahana import templates are stored in: static/formats/*/import.xsl

Background Info and Resources

Sahana XSLT/XPath capability is provided by ​lxml. Currently lxml only supports XSLT/XPath 1.0.

• ​XSLT Tutorial on w3schools
• ​XPath Tutorial on w3schools
• ​XSLT starter resources by Dave Pawson
• ​XSLT FAQ by Dave Pawson
• ​XSLT V2 reference on W3C
• ​XPath V2 reference on W3C
• ​interactive xslt environment

Debugging

Basic stylesheet checking can be done outside Sahana using the same functions as-used internally:

• /static/scripts/tools/xsltransform.py
• /static/scripts/tools/csv2xml.py

Full debugging can be done using Xalan. Start by converting smaller extracts in debug mode:

java -jar xalan.jar -param name shelter -param xsltmode extended -tt -tg -ts -in japanquake2011_shelter_extract.kml -xsl web2py\applications\eden\static\formats\kml\import.xsl -out shelters.xml

Then process the full thing in non-debug mode:

java -jar xalan.jar -param name shelter -param xsltmode extended -in japanquake2011_shelter.kml -xsl web2py\applications\eden\static\formats\kml\import.xsl -out shelters.xml

For a graphical IDE (Java, so cross-platform), you can trial ​EditX

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