Changed schema for Value -> Term, majorly breaking change (#622)

* Changed schema for Value -> Term, majorly breaking change

* Following the schema change, Value -> Term into all processing

* Updated Cassandra for g, p, s, o index patterns (7 indexes)

* Reviewed and updated all tests

* Neo4j, Memgraph and FalkorDB remain broken, will look at once settled down

trustgraph-base/trustgraph/base/document_embeddings_query_service.py

@@ -7,7 +7,7 @@ embeddings.
 import logging
 
 from .. schema import DocumentEmbeddingsRequest, DocumentEmbeddingsResponse
-from .. schema import Error, Value
+from .. schema import Error, Term
 
 from . flow_processor import FlowProcessor
 from . consumer_spec import ConsumerSpec

trustgraph-base/trustgraph/base/graph_embeddings_client.py

@@ -2,15 +2,21 @@
 import logging
 
 from . request_response_spec import RequestResponse, RequestResponseSpec
-from .. schema import GraphEmbeddingsRequest, GraphEmbeddingsResponse
+from .. schema import GraphEmbeddingsRequest, GraphEmbeddingsResponse, IRI, LITERAL
 from .. knowledge import Uri, Literal
 
 # Module logger
 logger = logging.getLogger(__name__)
 
+
 def to_value(x):
-    if x.is_uri: return Uri(x.value)
-    return Literal(x.value)
+    """Convert schema Term to Uri or Literal."""
+    if x.type == IRI:
+        return Uri(x.iri)
+    elif x.type == LITERAL:
+        return Literal(x.value)
+    # Fallback
+    return Literal(x.value or x.iri)
 
 class GraphEmbeddingsClient(RequestResponse):
     async def query(self, vectors, limit=20, user="trustgraph",

trustgraph-base/trustgraph/base/graph_embeddings_query_service.py

@@ -7,7 +7,7 @@ embeddings.
 import logging
 
 from .. schema import GraphEmbeddingsRequest, GraphEmbeddingsResponse
-from .. schema import Error, Value
+from .. schema import Error, Term
 
 from . flow_processor import FlowProcessor
 from . consumer_spec import ConsumerSpec

trustgraph-base/trustgraph/base/triples_client.py

@@ -1,24 +1,34 @@
 
 from . request_response_spec import RequestResponse, RequestResponseSpec
-from .. schema import TriplesQueryRequest, TriplesQueryResponse, Value
+from .. schema import TriplesQueryRequest, TriplesQueryResponse, Term, IRI, LITERAL
 from .. knowledge import Uri, Literal
 
+
 class Triple:
     def __init__(self, s, p, o):
         self.s = s
         self.p = p
         self.o = o
 
+
 def to_value(x):
-    if x.is_uri: return Uri(x.value)
-    return Literal(x.value)
+    """Convert schema Term to Uri or Literal."""
+    if x.type == IRI:
+        return Uri(x.iri)
+    elif x.type == LITERAL:
+        return Literal(x.value)
+    # Fallback
+    return Literal(x.value or x.iri)
+
 
 def from_value(x):
-    if x is None: return None
+    """Convert Uri or Literal to schema Term."""
+    if x is None:
+        return None
     if isinstance(x, Uri):
-        return Value(value=str(x), is_uri=True)
+        return Term(type=IRI, iri=str(x))
     else:
-        return Value(value=str(x), is_uri=False)
+        return Term(type=LITERAL, value=str(x))
 
 class TriplesClient(RequestResponse):
     async def query(self, s=None, p=None, o=None, limit=20,

trustgraph-base/trustgraph/base/triples_query_service.py

@@ -7,7 +7,7 @@ null.  Output is a list of triples.
 import logging
 
 from .. schema import TriplesQueryRequest, TriplesQueryResponse, Error
-from .. schema import Value, Triple
+from .. schema import Term, Triple
 
 from . flow_processor import FlowProcessor
 from . consumer_spec import  ConsumerSpec