GeoNode update_metadata

geonode-update-metadata

def update_metadata(layer_uuid, xml, saved_layer):
    """Update metadata XML document with GeoNode specific values"""
    # check if document is XML
    try:
        exml = etree.fromstring(xml)
    except Exception, err:
        raise GeoNodeException('Uploaded XML document is not XML: %s' % str(err))
    # check if document is an accepted XML metadata format
    try:
        tagname = exml.tag.split('}')[1]
    except:
        tagname = exml.tag
    # update relevant XML
    layer_updated = saved_layer.date.strftime('%Y-%m-%d')
    if tagname == 'Record': # Dublin Core
        dc_ns = '{http://purl.org/dc/elements/1.1/}'
        dct_ns ='{http://purl.org/dc/terms/}'
        children = exml.getchildren()
        # set/update identifier
        xname = exml.find('%sidentifier' % dc_ns)
        if xname is None: # doesn't exist, insert it

            value = etree.Element('%sidentifier' % dc_ns)

            value.text = layer_uuid

            children.insert(0, value)

        else: # exists, update it

            xname.text = layer_uuid


        xname = exml.find('%smodified' % dct_ns)

        if xname is None: # doesn't exist, insert it

            value = etree.Element('%smodified' % dct_ns)

            value.text = layer_updated

            children.insert(3, value)

        else: # exists, update it

            xname.text = layer_updated


        # set/update URLs

        http_link = etree.Element('%sreferences' % dct_ns, scheme='WWW:LINK-1.0-http--link')

        http_link.text = '%s%s' % (settings.SITEURL, saved_layer.get_absolute_url())

        children.insert(-2, http_link)


        for link in saved_layer.link_set.all():

            http_link = etree.Element('%sreferences' % dct_ns, scheme='WWW:DOWNLOAD-1.0-http--download')

            http_link.text = link.url

            children.insert(-2, http_link)


    elif tagname == 'MD_Metadata':

        gmd_ns = 'http://www.isotc211.org/2005/gmd'

        gco_ns = 'http://www.isotc211.org/2005/gco'


        # set/update gmd:fileIdentifier

        xname = exml.find('{%s}fileIdentifier' % gmd_ns)

        if xname is None: # doesn't exist, insert it

            children = exml.getchildren()

            fileid = etree.Element('{%s}fileIdentifier' % gmd_ns)

            etree.SubElement(fileid, '{%s}CharacterString' % gco_ns).text = layer_uuid

            children.insert(0, fileid)

        else: # gmd:fileIdentifier exists, check for gco:CharacterString

            value = xname.find('{%s}CharacterString' % gco_ns)

            if value is None:

                etree.SubElement(xname, '{%s}CharacterString' % gco_ns).text = layer_uuid

            else:

                value.text = layer_uuid


        # set/update gmd:dateStamp

        xname = exml.find('{%s}dateStamp' % gmd_ns)

        if xname is None: # doesn't exist, insert it

            children = exml.getchildren()

            datestamp = etree.Element('{%s}dateStamp' % gmd_ns)

            etree.SubElement(datestamp, '{%s}DateTime' % gco_ns).text = layer_updated

            children.insert(4, datestamp)

        else: # gmd:dateStamp exists, check for gco:Date or gco:DateTime

            value = xname.find('{%s}Date' % gco_ns)

            value2 = xname.find('{%s}DateTime' % gco_ns)


            if value is None and value2 is not None: # set gco:DateTime

                value2.text = layer_updated

            elif value is not None and value2 is None: # set gco:Date

                value.text = saved_layer.date.strftime('%Y-%m-%d')

            elif value is None and value2 is None:

                etree.SubElement(xname, '{%s}DateTime' % gco_ns).text = layer_updated


        # set/update URLs

        children = exml.getchildren()

        distinfo = etree.Element('{%s}distributionInfo' % gmd_ns)

        distinfo2 = etree.SubElement(distinfo, '{%s}MD_Distribution' % gmd_ns)

        transopts = etree.SubElement(distinfo2, '{%s}transferOptions' % gmd_ns)

        transopts2 = etree.SubElement(transopts, '{%s}MD_DigitalTransferOptions' % gmd_ns)


        online = etree.SubElement(transopts2, '{%s}onLine' % gmd_ns)

        online2 = etree.SubElement(online, '{%s}CI_OnlineResource' % gmd_ns)

        linkage = etree.SubElement(online2, '{%s}linkage' % gmd_ns)

        etree.SubElement(linkage, '{%s}URL' % gmd_ns).text = '%s%s' % (settings.SITEURL, saved_layer.get_absolute_url())

        protocol = etree.SubElement(online2, '{%s}protocol' % gmd_ns)

        etree.SubElement(protocol, '{%s}CharacterString' % gco_ns).text = 'WWW:LINK-1.0-http--link'


        for extension, dformat, dprotocol, link in saved_layer.download_links():

            online = etree.SubElement(transopts2, '{%s}onLine' % gmd_ns)

            online2 = etree.SubElement(online, '{%s}CI_OnlineResource' % gmd_ns)

            linkage = etree.SubElement(online2, '{%s}linkage' % gmd_ns)


            etree.SubElement(linkage, '{%s}URL' % gmd_ns).text = link or ''

            protocol = etree.SubElement(online2, '{%s}protocol' % gmd_ns)

            etree.SubElement(protocol, '{%s}CharacterString' % gco_ns).text = dprotocol

            lname = etree.SubElement(online2, '{%s}name' % gmd_ns)

            etree.SubElement(lname, '{%s}CharacterString' % gco_ns).text = extension or ''

            ldesc = etree.SubElement(online2, '{%s}description' % gmd_ns)

            etree.SubElement(ldesc, '{%s}CharacterString' % gco_ns).text = dformat or ''


        children.insert(-2, distinfo)


    elif tagname == 'metadata': # FGDC

        # set/update identifier

        xname = exml.find('idinfo/datasetid')

        if xname is None: # doesn't exist, insert it

            children = exml.find('idinfo').getchildren()

            value = etree.Element('datasetid')

            value.text = layer_uuid

            children.insert(0, value)

        else: # exists, update it

            xname.text = layer_uuid

        xname = exml.find('metainfo/metd')

        if xname is None: # doesn't exist, insert it

            value = etree.Element('metd')

            value.text = layer_updated

            exml.find('metainfo').append(value)

        else: # exists, update it

            xname.text = layer_updated


        # set/update URLs

        citeinfo = exml.find('idinfo/citation/citeinfo')

        http_link = etree.Element('onlink')

        http_link.attrib['type'] = 'WWW:LINK-1.0-http--link'

        http_link.text = '%s%s' % (settings.SITEURL, saved_layer.get_absolute_url())

        citeinfo.append(http_link)


        for extension, dformat, protocol, link in saved_layer.download_links():

            http_link = etree.Element('onlink')

            http_link.attrib['type'] = protocol

            http_link.text = link

            citeinfo.append(http_link)


    else:

        raise GeoNodeException('Unsupported metadata format')
	  	

    return etree.tostring(exml)