Support #26

-   Adds a predicate handler (URI handler) for slots that describe a single URI
-   Validates the URI per RFC-3986
-   Adds an upgrade step that
    -   Makes the new handler available
    -   Deletes the current "Person" generator's `Photo_file_name` handler
    -   Replaces it with a new `Photo_file_name` handler that uses the URI handler

src/edrn.rdf/edrn/rdf/configure.zcml

@@ -98,6 +98,11 @@ RESERVED. U.S. Government Sponsorship acknowledged.
         provides='.interfaces.IAsserter'
         for='.literalpredicatehandler.ILiteralPredicateHandler'
     />
+    <adapter
+        factory='.uripredicatehandler.URIAsserter'
+        provides='.interfaces.IAsserter'
+        for='.uripredicatehandler.IURIPredicateHandler'
+    />
     <adapter
         factory='.multiliteralpredicatehandler.MultiLiteralAsserter'
         provides='.interfaces.IAsserter'

src/edrn.rdf/edrn/rdf/profiles/default/metadata.xml

@@ -4,7 +4,7 @@ Copyright 2012–2023 California Institute of Technology. ALL RIGHTS
 RESERVED. U.S. Government Sponsorship acknowledged.
 -->
 <metadata>
-    <version>11</version>
+    <version>12</version>
     <description>EDRN RDF Service</description>
     <dependencies>
         <dependency>profile-plone.app.dexterity:default</dependency>

src/edrn.rdf/edrn/rdf/profiles/default/types.xml

@@ -1,6 +1,6 @@
 <?xml version='1.0' encoding='UTF-8'?>
 <!--
-Copyright 2008—2012 California Institute of Technology. ALL RIGHTS
+Copyright 2008—2024 California Institute of Technology. ALL RIGHTS
 RESERVED. U.S. Government Sponsorship acknowledged.
 -->
 <object name='portal_types' meta_type='Plone Types Tool'>
@@ -11,6 +11,7 @@ RESERVED. U.S. Government Sponsorship acknowledged.
     <object name='edrn.rdf.dmcccommitteerdfgenerator' meta_type='Dexterity FTI' />
     <object name='edrn.rdf.dmccprotocolrdfgenerator' meta_type='Dexterity FTI' />
     <object name='edrn.rdf.literalpredicatehandler' meta_type='Dexterity FTI' />
+    <object name='edrn.rdf.uripredicatehandler' meta_type='Dexterity FTI' />
     <object name='edrn.rdf.multiliteralpredicatehandler' meta_type='Dexterity FTI' />
     <object name='edrn.rdf.multipipepredicatehandler' meta_type='Dexterity FTI' />
     <object name='edrn.rdf.referencepredicatehandler' meta_type='Dexterity FTI' />

src/edrn.rdf/edrn/rdf/profiles/default/types/edrn.rdf.simpledmccrdfgenerator.xml

@@ -14,6 +14,7 @@ sets of data available at the DMCC by accessing their crummy web service.</prope
     <property name='filter_content_types'>True</property>
     <property name='allowed_content_types'>
         <element value='edrn.rdf.literalpredicatehandler' />
+        <element value='edrn.rdf.uripredicatehandler' />        
         <element value='edrn.rdf.multiliteralpredicatehandler' />
         <element value='edrn.rdf.multipipepredicatehandler' />
         <element value='edrn.rdf.referencepredicatehandler' />

src/edrn.rdf/edrn/rdf/profiles/default/types/edrn.rdf.uripredicatehandler.xml

@@ -0,0 +1,35 @@
+<?xml version='1.0' encoding='utf-8'?>
+<!--
+Copyright 2024 California Institute of Technology. ALL RIGHTS
+RESERVED. U.S. Government Sponsorship acknowledged.
+-->
+<object name='edrn.rdf.uripredicatehandler' meta_type='Dexterity FTI' i18n:domain='edrn.rdf'
+    xmlns:i18n='http://xml.zope.org/namespaces/i18n'>
+    <property name='title' i18n:translate=''>URI Predicate Handler</property>
+    <property name='description' i18n:translate=''>A handler for DMCC web services that maps a singel URI to a single RDF resource reference.</property>
+    <property name='allow_discussion'>False</property>
+    <property name='global_allow'>False</property>
+    <property name='filter_content_types'>True</property>
+    <property name='allowed_content_types' />
+    <property name='schema'>edrn.rdf.uripredicatehandler.IURIPredicateHandler</property>
+    <property name='klass'>plone.dexterity.content.Item</property>
+    <property name='add_permission'>cmf.AddPortalContent</property>
+    <property name='behaviors'>
+        <element value='plone.app.content.interfaces.INameFromTitle' />
+    </property>
+    <property name='default_view'>view</property>
+    <property name='default_view_fallback'>False</property>
+    <property name='view_methods'>
+        <element value='view' />
+    </property>
+    <alias from='(Default)' to='(dynamic view)' />
+    <alias from='edit' to='@@edit' />
+    <alias from='sharing' to='@@sharing' />
+    <alias from='view' to='(selected layout)' />
+    <action title='View' action_id='view' category='object' condition_expr='' url_expr='string:${object_url}' visible='True'>
+        <permission value='View' />
+    </action>
+    <action title='Edit' action_id='edit' category='object' condition_expr='' url_expr='string:${object_url}/edit' visible='True'>
+        <permission value='Modify portal content' />
+    </action>
+</object>

src/edrn.rdf/edrn/rdf/upgrades.py

@@ -166,3 +166,24 @@ def upgrade10to11(setupTool, logger=None):
     if logger is None:
         logger = logging.getLogger(PACKAGE_NAME)
     setupTool.runImportStepFromProfile(DEFAULT_PROFILE, 'typeinfo')
+
+
+def upgrade11to12(setupTool, logger=None):
+    if logger is None:
+        logger = logging.getLogger(PACKAGE_NAME)
+    setupTool.runImportStepFromProfile(DEFAULT_PROFILE, 'typeinfo')
+    portal = plone.api.portal.get()
+    generator = portal.unrestrictedTraverse('rdf-generators/person-generator')
+    try:
+        generator.manage_delObject('Photo_file_name')
+    except AttributeError:
+        # no photo file handler found, so no worries
+        pass
+    handler = createContentInContainer(
+        generator,
+        'edrn.rdf.uripredicatehandler',
+        title='Photo_file_name',
+        description='A URL to a photograph of the person',
+        predicateURI='http://xmlns.com/foaf/0.1/img'
+    )
+    publish(handler, plone.api.portal.get_tool('portal_workflow'))

src/edrn.rdf/edrn/rdf/upgrades.zcml

@@ -85,6 +85,15 @@ RESERVED. U.S. Government Sponsorship acknowledged.
         handler='edrn.rdf.upgrades.upgrade10to11'
         sortkey='1'
     />
+    <genericsetup:upgradeStep
+        source='11'
+        destination='12'
+        title='Upgrade 11 to 12'
+        description='Add new URI predicate handler'
+        profile='edrn.rdf:default'
+        handler='edrn.rdf.upgrades.upgrade11to12'
+        sortkey='1'
+    />
 
 
 </configure>

src/edrn.rdf/edrn/rdf/uripredicatehandler.py

@@ -0,0 +1,32 @@
+# encoding: utf-8
+# Copyright 2024 California Institute of Technology. ALL RIGHTS
+# RESERVED. U.S. Government Sponsorship acknowledged.
+
+from .predicatehandler import ISimplePredicateHandler
+from Acquisition import aq_inner
+from rfc3986_validator import validate_rfc3986
+import rdflib, logging
+
+_logger = logging.getLogger(__name__)
+
+
+class IURIPredicateHandler(ISimplePredicateHandler):
+    '''A handler for DMCC web services that contains single URI references.'''
+    pass
+
+
+class URIAsserter(object):
+    '''Describes subjects using a predicate with a single complementary references to some other URI.'''
+    def __init__(self, context):
+        self.context = context
+
+    def characterize(self, obj):
+        context = aq_inner(self.context)
+
+        if validate_rfc3986(obj):
+            return [(rdflib.URIRef(context.predicateURI), rdflib.URIRef(obj))]
+        else:
+            _logger.warning(
+                "Got an invalid URI «%s» for %s which won't be put into RDF", obj, self.context.title
+            )
+            return []