Merge pull request #95 from adamnsch/graph-get-error-msg

Add transparency of currently targeted database

Author: adamnsch

changelog/1.1.0.md

@@ -12,6 +12,7 @@
 * Added support for new GDS library 2.1 signature of gds.graph.removeNodeProperties.
 * Added support for new function `gds.close` which calls `.close()` on a `GraphDataScience` object's underlying Neo4j driver.
 * Added new method `gds.alpha.graph.construct` to construct a GDS graph from pandas `DataFrame`s, which works if the GDS Flight server is enabled.
+* Added new function `gds.database` which can be used to see which database is currently being targeted.
 
 
 ## Bug fixes
@@ -20,6 +21,7 @@
 ## Improvements
 
 * The functions `gds.graph.streamNodeProperty` and `gds.graph.streamRelationshipProperty` can leverage the Arrow Flight server of GDS to improve throughput.
+* Improved error message of `gds.graph.get` to include currently targeted database if graph not found.
 
 
 ## Other changes

graphdatascience/graph/graph_proc_runner.py

@@ -76,7 +76,9 @@ def list(self, G: Optional[Graph] = None) -> DataFrame:
     @client_only_endpoint("gds.graph")
     def get(self, graph_name: str) -> Graph:
         if not self.exists(graph_name)["exists"]:
-            raise ValueError(f"No projected graph named '{graph_name}' exists")
+            raise ValueError(
+                f"No projected graph named '{graph_name}' exists in current database '{self._query_runner.database()}'"
+            )
 
         return Graph(graph_name, self._query_runner, self._server_version)
 

graphdatascience/graph_data_science.py

@@ -89,6 +89,9 @@ def __getattr__(self, attr: str) -> CallBuilder:
     def set_database(self, db: str) -> None:
         self._query_runner.set_database(db)
 
+    def database(self) -> str:
+        return self._query_runner.database()
+
     def run_cypher(self, query: str, params: Dict[str, Any] = {}) -> DataFrame:
         return self._query_runner.run_query(query, params)
 

graphdatascience/tests/integration/test_graph_ops.py

@@ -142,7 +142,10 @@ def test_graph_get(gds: GraphDataScience) -> None:
     G = gds.graph.get(GRAPH_NAME)
     assert G.name() == GRAPH_NAME
 
-    with pytest.raises(ValueError):
+    with pytest.raises(
+        ValueError,
+        match=f"No projected graph named 'bogusName' exists in current database '{gds.database()}'",
+    ):
         gds.graph.get("bogusName")