change the SPARQL query to find all learning resources for a given community

RDF modeling has changed from mo:hasCommunity to rec:recommender and/or bflr:supportinghost

project/dalia/query/communities/community_items.py

@@ -7,8 +7,8 @@ from project.dalia.api_models.api_models import Item
 from project.dalia.query.communities.communities import get_metadata_for_communities
 from project.dalia.query.items.metadata.items import get_metadata_for_learning_resources
 from project.dalia.query.utils import query_dalia_dataset
-from project.dalia.query_builder.query_builder import QueryBuilder, VALUES
-from project.dalia.rdf.namespace import MoDalia, educor
+from project.dalia.query_builder.query_builder import GROUP, QueryBuilder, UNION, VALUES
+from project.dalia.rdf.namespace import MoDalia, bibframe_lite_relation, educor, rec
 from project.dalia.rdf.prefix import COMMUNITIES_BASE_URI
 
 
@@ -50,13 +50,21 @@ def prepare_query_for_resources_of_community(community_uri_ref: URIRef) -> str:
     var_community = Variable("community")
 
     return QueryBuilder().SELECT(
-        var_lr
+        var_lr,
+        distinct=True  # prevents duplicates in case the same community is both rec:recommender and bflr:supportinghost
     ).WHERE(
         VALUES(
             [var_community],
             [[community_uri_ref]]
         ),
         (var_community, RDF.type, MoDalia.Community),
-        (var_lr, MoDalia.hasCommunity, var_community),
+        # This GROUP-UNION pattern is equivalent to "?lr rec:recommender|bflr:supportinghost ?community"
+        # (AlternativePath expression in SPARQL).
+        GROUP(
+            (var_lr, rec.recommender, var_community),
+        ),
+        UNION(
+            (var_lr, bibframe_lite_relation.supportinghost, var_community),
+        ),
         (var_lr, RDF.type, educor.EducationalResource)
     ).build()

project/dalia/rdf/namespace/MoDalia.py

@@ -6,7 +6,6 @@ from rdflib import URIRef
 NS = "https://purl.org/ontology/modalia#"
 
 # Properties
-hasCommunity = URIRef(NS + "hasCommunity")
 hasLearningType = URIRef(NS + "hasLearningType")
 hasMediaType = URIRef(NS + "hasMediaType")
 hasTargetGroup = URIRef(NS + "hasTargetGroup")