make diff responses consistent with NULL vs being empty (#4242)

* make diff responses consistent with NULL vs being empty

* mypy fix

backend/infrahub/core/diff/query/diff_summary.py

@@ -92,10 +92,13 @@ async def query_init(self, db: InfrahubDatabase, **kwargs: Any) -> None:
             "SUM(diff_node.num_conflicts) as num_conflicts",
             "min(diff_root.from_time) as from_time",
             "max(diff_root.to_time) as to_time",
+            "count(diff_root) as num_roots",
         ]
 
-    def get_summary(self) -> DiffSummaryCounters:
+    def get_summary(self) -> DiffSummaryCounters | None:
         result = self.get_result()
         if not result:
-            return DiffSummaryCounters(from_time=self.from_time, to_time=self.to_time)
+            return None
+        if result.get("num_roots") == 0:
+            return None
         return DiffSummaryCounters.from_graph(result)

backend/infrahub/core/diff/repository/repository.py

@@ -87,7 +87,7 @@ async def summary(
         from_time: Timestamp,
         to_time: Timestamp,
         filters: dict | None = None,
-    ) -> DiffSummaryCounters:
+    ) -> DiffSummaryCounters | None:
         query = await DiffSummaryQuery.init(
             db=self.db,
             base_branch_name=base_branch_name,

backend/infrahub/graphql/queries/diff/tree.py

@@ -401,6 +401,7 @@ async def resolve(
             include_parents=include_parents,
             limit=limit,
             offset=offset,
+            include_empty=True,
         )
         if not enriched_diffs:
             return None
@@ -454,6 +455,8 @@ async def summary(
             to_time=to_timestamp,
             filters=filters_dict,
         )
+        if summary is None:
+            return None
 
         diff_tree_summary = DiffTreeSummary(
             base_branch=base_branch.name,

backend/tests/unit/graphql/test_diff_tree_query.py

@@ -195,7 +195,43 @@ async def diff_coordinator(db: InfrahubDatabase, diff_branch: Branch) -> DiffCoo
     return coordinator
 
 
-async def test_diff_tree_empty_diff(
+async def test_diff_tree_no_changes(
+    db: InfrahubDatabase,
+    default_branch: Branch,
+    criticality_low,
+    diff_coordinator: DiffCoordinator,
+    diff_branch: Branch,
+):
+    enriched_diff = await diff_coordinator.update_branch_diff(base_branch=default_branch, diff_branch=diff_branch)
+    from_time = datetime.fromisoformat(diff_branch.created_at)
+    to_time = datetime.fromisoformat(enriched_diff.to_time.to_string())
+
+    params = prepare_graphql_params(db=db, include_mutation=False, include_subscription=False, branch=default_branch)
+    result = await graphql(
+        schema=params.schema,
+        source=DIFF_TREE_QUERY,
+        context_value=params.context,
+        root_value=None,
+        variable_values={"branch": diff_branch.name},
+    )
+
+    assert result.errors is None
+    assert result.data["DiffTree"] == {
+        "base_branch": default_branch.name,
+        "diff_branch": diff_branch.name,
+        "from_time": from_time.isoformat(),
+        "to_time": to_time.isoformat(),
+        "num_added": 0,
+        "num_removed": 0,
+        "num_updated": 0,
+        "num_conflicts": 0,
+        "num_untracked_base_changes": 0,
+        "num_untracked_diff_changes": 0,
+        "nodes": [],
+    }
+
+
+async def test_diff_tree_no_diffs(
     db: InfrahubDatabase, default_branch: Branch, criticality_schema: NodeSchema, diff_branch: Branch
 ):
     params = prepare_graphql_params(db=db, include_mutation=False, include_subscription=False, branch=default_branch)
@@ -636,6 +672,58 @@ async def test_diff_tree_hierarchy_change(
     assert nodes_parent == expected_nodes_parent
 
 
+async def test_diff_tree_summary_no_diffs(
+    db: InfrahubDatabase, default_branch: Branch, criticality_schema: NodeSchema, diff_branch: Branch
+):
+    params = prepare_graphql_params(db=db, include_mutation=False, include_subscription=False, branch=default_branch)
+    result = await graphql(
+        schema=params.schema,
+        source=DIFF_TREE_QUERY_SUMMARY,
+        context_value=params.context,
+        root_value=None,
+        variable_values={"branch": diff_branch.name},
+    )
+
+    assert result.errors is None
+    assert result.data["DiffTreeSummary"] is None
+
+
+async def test_diff_tree_summary_no_changes(
+    db: InfrahubDatabase,
+    default_branch: Branch,
+    criticality_low,
+    diff_coordinator: DiffCoordinator,
+    diff_branch: Branch,
+):
+    enriched_diff = await diff_coordinator.update_branch_diff(base_branch=default_branch, diff_branch=diff_branch)
+    from_time = datetime.fromisoformat(diff_branch.created_at)
+    to_time = datetime.fromisoformat(enriched_diff.to_time.to_string())
+
+    params = prepare_graphql_params(db=db, include_mutation=False, include_subscription=False, branch=default_branch)
+    result = await graphql(
+        schema=params.schema,
+        source=DIFF_TREE_QUERY_SUMMARY,
+        context_value=params.context,
+        root_value=None,
+        variable_values={"branch": diff_branch.name},
+    )
+
+    assert result.errors is None
+    assert result.data["DiffTreeSummary"] == {
+        "base_branch": default_branch.name,
+        "diff_branch": diff_branch.name,
+        "from_time": from_time.isoformat(),
+        "to_time": to_time.isoformat(),
+        "num_added": 0,
+        "num_removed": 0,
+        "num_updated": 0,
+        "num_unchanged": 0,
+        "num_conflicts": 0,
+        "num_untracked_base_changes": 0,
+        "num_untracked_diff_changes": 0,
+    }
+
+
 @pytest.mark.parametrize(
     "filters,counters",
     [