Move sparql_delta to LdpRs class; add message for empty results or tombstone

on non-strict IMR extraction.

lakesuperior/model/ldp_rs.py

@@ -1,3 +1,5 @@
+from copy import deepcopy
+
 from lakesuperior.dictionaries.namespaces import ns_collection as nsc
 from lakesuperior.model.ldpr import Ldpr, atomic
 
@@ -43,6 +45,48 @@ class LdpRs(Ldpr):
         return self._modify_rsrc(self.RES_UPDATED, *delta)
 
 
+    def _sparql_delta(self, q):
+        '''
+        Calculate the delta obtained by a SPARQL Update operation.
+
+        This is a critical component of the SPARQL query prcess and does a
+        couple of things:
+
+        1. It ensures that no resources outside of the subject of the request
+        are modified (e.g. by variable subjects)
+        2. It verifies that none of the terms being modified is server managed.
+
+        This method extracts an in-memory copy of the resource and performs the
+        query on that once it has checked if any of the server managed terms is
+        in the delta. If it is, it raises an exception.
+
+        NOTE: This only checks if a server-managed term is effectively being
+        modified. If a server-managed term is present in the query but does not
+        cause any change in the updated resource, no error is raised.
+
+        @return tuple(rdflib.Graph) Remove and add graphs. These can be used
+        with `BaseStoreLayout.update_resource` and/or recorded as separate
+        events in a provenance tracking system.
+        '''
+        self._logger.debug('Provided SPARQL query: {}'.format(q))
+        pre_gr = self.imr.graph
+
+        post_gr = deepcopy(pre_gr)
+        post_gr.update(q)
+
+        remove_gr, add_gr = self._dedup_deltas(pre_gr, post_gr)
+
+        #self._logger.info('Removing: {}'.format(
+        #    remove_gr.serialize(format='turtle').decode('utf8')))
+        #self._logger.info('Adding: {}'.format(
+        #    add_gr.serialize(format='turtle').decode('utf8')))
+
+        remove_gr = self._check_mgd_terms(remove_gr)
+        add_gr = self._check_mgd_terms(add_gr)
+
+        return remove_gr, add_gr
+
+
 
 class Ldpc(LdpRs):
     '''LDPC (LDP Container).'''

lakesuperior/model/ldpr.py

@@ -2,7 +2,6 @@ import logging
 
 from abc import ABCMeta
 from collections import defaultdict
-from copy import deepcopy
 from itertools import accumulate, groupby
 from pprint import pformat
 from uuid import uuid4
@@ -804,47 +803,6 @@ class Ldpr(metaclass=ABCMeta):
         return gr
 
 
-    def _sparql_delta(self, q):
-        '''
-        Calculate the delta obtained by a SPARQL Update operation.
-
-        This is a critical component of the SPARQL query prcess and does a
-        couple of things:
-
-        1. It ensures that no resources outside of the subject of the request
-        are modified (e.g. by variable subjects)
-        2. It verifies that none of the terms being modified is server managed.
-
-        This method extracts an in-memory copy of the resource and performs the
-        query on that once it has checked if any of the server managed terms is
-        in the delta. If it is, it raises an exception.
-
-        NOTE: This only checks if a server-managed term is effectively being
-        modified. If a server-managed term is present in the query but does not
-        cause any change in the updated resource, no error is raised.
-
-        @return tuple(rdflib.Graph) Remove and add graphs. These can be used
-        with `BaseStoreLayout.update_resource` and/or recorded as separate
-        events in a provenance tracking system.
-        '''
-        pre_gr = self.imr.graph
-
-        post_gr = deepcopy(pre_gr)
-        post_gr.update(q)
-
-        remove_gr, add_gr = self._dedup_deltas(pre_gr, post_gr)
-
-        #self._logger.info('Removing: {}'.format(
-        #    remove_gr.serialize(format='turtle').decode('utf8')))
-        #self._logger.info('Adding: {}'.format(
-        #    add_gr.serialize(format='turtle').decode('utf8')))
-
-        remove_gr = self._check_mgd_terms(remove_gr)
-        add_gr = self._check_mgd_terms(add_gr)
-
-        return remove_gr, add_gr
-
-
     def _add_srv_mgd_triples(self, create=False):
         '''
         Add server-managed triples to a provided IMR.

lakesuperior/store_layouts/ldp_rs/default_layout.py

@@ -90,16 +90,21 @@ class DefaultLayout(BaseRdfLayout):
         rsrc = Resource(gr, uri)
 
         # Check if resource is a tombstone.
-        if strict:
-            if rsrc[RDF.type : nsc['fcsystem'].Tombstone]:
+        if rsrc[RDF.type : nsc['fcsystem'].Tombstone]:
+            if strict:
                 raise TombstoneError(
                         g.tbox.uri_to_uuid(rsrc.identifier),
                         rsrc.value(nsc['fcrepo'].created))
-            elif rsrc.value(nsc['fcsystem'].tombstone):
+            else:
+                self._logger.info('No resource found: {}'.format(uri))
+        elif rsrc.value(nsc['fcsystem'].tombstone):
+            if strict:
                 raise TombstoneError(
                         g.tbox.uri_to_uuid(
                             rsrc.value(nsc['fcsystem'].tombstone).identifier),
                         rsrc.value(nsc['fcrepo'].created))
+            else:
+                self._logger.info('Tombstone found: {}'.format(uri))
 
         return rsrc