Merge pull request #1211 from edmondchuc/feat/sparql-result-serialize…

…r-docs

Add documentation and type hints for rdflib.query.Result and rdflib.graph.Graph

rdflib/graph.py

@@ -1130,13 +1130,13 @@ def load(self, source, publicID=None, format="xml"):
     def query(
         self,
         query_object,
-        processor="sparql",
-        result="sparql",
+        processor: str = "sparql",
+        result: str = "sparql",
         initNs=None,
         initBindings=None,
-        use_store_provided=True,
+        use_store_provided: bool = True,
         **kwargs
-    ):
+    ) -> query.Result:
         """
         Query this graph.
 
@@ -1147,7 +1147,7 @@ def query(
         if none are given, the namespaces from the graph's namespace manager
         are used.
 
-        :returntype: rdflib.query.QueryResult
+        :returntype: rdflib.query.Result
 
         """
 

rdflib/query.py

@@ -4,6 +4,7 @@
 import tempfile
 import warnings
 import types
+from typing import Optional
 
 from io import BytesIO
 
@@ -205,8 +206,29 @@ def parse(source=None, format=None, content_type=None, **kwargs):
 
         return parser.parse(source, content_type=content_type, **kwargs)
 
-    def serialize(self, destination=None, encoding="utf-8", format="xml", **args):
-
+    def serialize(
+            self,
+            destination: Optional[str] = None,
+            encoding: str = "utf-8",
+            format: str = "xml",
+            **args,
+    ) -> Optional[bytes]:
+        """
+        Serialize the query result.
+
+        The :code:`format` argument determines the Serializer class to use.
+
+        - csv: :class:`~rdflib.plugins.sparql.results.csvresults.CSVResultSerializer`
+        - json: :class:`~rdflib.plugins.sparql.results.jsonresults.JSONResultSerializer`
+        - txt: :class:`~rdflib.plugins.sparql.results.txtresults.TXTResultSerializer`
+        - xml: :class:`~rdflib.plugins.sparql.results.xmlresults.XMLResultSerializer`
+
+        :param destination: Path of file output.
+        :param encoding: Encoding of output.
+        :param format: One of ['csv', 'json', 'txt', xml']
+        :param args:
+        :return: bytes
+        """
         if self.type in ("CONSTRUCT", "DESCRIBE"):
             return self.graph.serialize(
                 destination, encoding=encoding, format=format, **args