Xpath Store

This store is another use of the local cache directory. It basically enables users to perform xpath queries on subjects XML documents. It also provides a few utility functions to help figure out what information is in the documents.

An xpath example to retrieve the IDs from all the subjects in cache:

>>> central.xpath('//xnat:Subject/attribute::ID')

Download the XML documents from a project or from a subject list:

>>> central.xpath.checkout(project='my_project')
>>> central.xpath.checkout(subjects=['CENTRAL_00001', 'CENTRAL_00005'])

Update the subjects XML documents if any data related to them has changed on the server since the last update:

>>> central.xpath.update()

Helper methods to get the subject IDs, the subject attributes, the elements attached to subject and their attributes or text elements:

>>> central.xpath.subjects()
>>> central.xpath.keys()
>>> central.xpath.values('key')
>>> central.xpath.attrs()
>>> central.xpath.elements()
>>> central.xpath.element_keys('element_name')
>>> central.xpath.element_values('element_name')
>>> central.xpath.element_attrs('element_name')
>>> central.xpath.element_text('element_name')