feature: log error when sequence or scenario is not consistent

taipy/core/scenario/scenario.py

@@ -17,6 +17,7 @@ from typing import Any, Callable, Dict, List, Optional, Set, Union
 import networkx as nx
 
 from taipy.common.config.common._validate_id import _validate_id
+from taipy.common.logger._taipy_logger import _TaipyLogger
 
 from .._entity._entity import _Entity
 from .._entity._labeled import _Labeled
@@ -106,6 +107,8 @@ class Scenario(_Entity, Submittable, _Labeled):
     id: ScenarioId
     """The unique identifier of this scenario."""
 
+    _logger = _TaipyLogger._get_logger()
+
     def __init__(
         self,
         config_id: str,
@@ -611,12 +614,32 @@ class Scenario(_Entity, Submittable, _Labeled):
         if dag.number_of_nodes() == 0:
             return True
         if not nx.is_directed_acyclic_graph(dag):
+            self._logger.error(f'The DAG of scenario "{self.id}" is not a directed acyclic graph')
             return False
         for left_node, right_node in dag.edges:
             if (isinstance(left_node, DataNode) and isinstance(right_node, Task)) or (
                 isinstance(left_node, Task) and isinstance(right_node, DataNode)
             ):
                 continue
+
+            left_node_desc = (
+                f'{left_node.__class__.__name__} "{left_node.get_label()}"'
+                if isinstance(left_node, _Labeled)
+                else left_node.__class__.__name__
+                if left_node
+                else "None"
+            )
+            right_node_desc = (
+                f'{right_node.__class__.__name__} "{right_node.get_label()}"'
+                if isinstance(right_node, _Labeled)
+                else right_node.__class__.__name__
+                if right_node
+                else "None"
+            )
+            self._logger.error(
+                f'Invalid edge detected in scenario "{self.id}": left node {left_node_desc} and right node '
+                f"{right_node_desc} must connect a Task and a DataNode"
+            )
             return False
         return True
 

taipy/core/sequence/sequence.py

@@ -16,6 +16,7 @@ from typing import Any, Callable, Dict, List, Optional, Set, Union
 import networkx as nx
 
 from taipy.common.config.common._validate_id import _validate_id
+from taipy.common.logger._taipy_logger import _TaipyLogger
 
 from .._entity._entity import _Entity
 from .._entity._labeled import _Labeled
@@ -118,6 +119,8 @@ class Sequence(_Entity, Submittable, _Labeled):
     _MANAGER_NAME = "sequence"
     __CHECK_INIT_DONE_ATTR_NAME = "_init_done"
 
+    _logger = _TaipyLogger._get_logger()
+
     id: SequenceId
     """The unique identifier of the sequence."""
 
@@ -343,15 +346,37 @@ class Sequence(_Entity, Submittable, _Labeled):
         if dag.number_of_nodes() == 0:
             return True
         if not nx.is_directed_acyclic_graph(dag):
+            self._logger.error(f'The DAG of sequence "{self.id}" is not a directed acyclic graph')
             return False
         if not nx.is_weakly_connected(dag):
+            self._logger.error(f'The DAG of sequence "{self.id}" is not weakly connected')
             return False
         for left_node, right_node in dag.edges:
             if (isinstance(left_node, DataNode) and isinstance(right_node, Task)) or (
                 isinstance(left_node, Task) and isinstance(right_node, DataNode)
             ):
                 continue
+
+            left_node_desc = (
+                f'{left_node.__class__.__name__} "{left_node.get_label()}"'
+                if isinstance(left_node, _Labeled)
+                else left_node.__class__.__name__
+                if left_node
+                else "None"
+            )
+            right_node_desc = (
+                f'{right_node.__class__.__name__} "{right_node.get_label()}"'
+                if isinstance(right_node, _Labeled)
+                else right_node.__class__.__name__
+                if right_node
+                else "None"
+            )
+            self._logger.error(
+                f'Invalid edge detected in sequence "{self.id}": left node {left_node_desc} and right node '
+                f"{right_node_desc} must connect a Task and a DataNode"
+            )
             return False
+
         return True
 
     def _get_tasks(self) -> Dict[str, Task]:

tests/core/scenario/test_scenario.py

@@ -1538,3 +1538,25 @@ def test_check_consistency():
     task_5 = Task("bob", {}, print, [data_node_5], [data_node_3], TaskId("t5"))
     scenario_9 = Scenario("scenario_9", [task_1, task_2, task_3, task_4, task_5], {}, [], scenario_id=ScenarioId("s8"))
     assert scenario_9._is_consistent()
+
+
+def test_check_inconsistency(caplog):
+    class FakeDataNode:
+        config_id = "config_id_of_a_fake_dn"
+
+    data_node_1 = InMemoryDataNode("foo", Scope.SCENARIO, "s1")
+    data_node_2 = InMemoryDataNode("bar", Scope.SCENARIO, "s2")
+
+    task_1 = Task("grault", {}, print, [data_node_1, data_node_2], [FakeDataNode()], TaskId("t1"))
+    task_2 = Task("garply", {}, print, [data_node_1], [data_node_2], id=TaskId("t2"))
+    scenario_1 = Scenario("scenario_1", [task_1, task_2], {}, [], scenario_id=ScenarioId("s1"))
+    assert not scenario_1._is_consistent()
+    assert (
+        'Invalid edge detected in scenario "s1": left node Task "grault" and right node FakeDataNode'
+        " must connect a Task and a DataNode" in caplog.text
+    )
+
+    task_3 = Task("waldo", {}, print, [data_node_2], [data_node_1], id=TaskId("t3"))
+    scenario_2 = Scenario("scenario_2", [task_2, task_3], {}, [], scenario_id=ScenarioId("s2"))
+    assert not scenario_2._is_consistent()
+    assert 'The DAG of scenario "s2" is not a directed acyclic graph' in caplog.text

tests/core/sequence/test_sequence.py

@@ -30,6 +30,10 @@ from taipy.core.task._task_manager import _TaskManager
 from taipy.core.task.task import Task, TaskId
 
 
+class FakeDataNode:
+    config_id = "config_id_of_a_fake_dn"
+
+
 def test_sequence_equals():
     task_config = Config.configure_task("mult_by_3", print, [], None)
     scenario_config = Config.configure_scenario("scenario", [task_config])
@@ -143,7 +147,7 @@ def test_get_set_attribute():
         sequence.bar = "KeyAlreadyUsed"
 
 
-def test_check_consistency():
+def test_check_consistency(caplog):
     sequence_1 = Sequence({}, [], "name_1")
     assert sequence_1._is_consistent()
 
@@ -157,6 +161,7 @@ def test_check_consistency():
     task_3 = Task("tfoo", {}, print, [data_node_3], [data_node_3], TaskId("task_id_3"))
     sequence_3 = Sequence({}, [task_3], "name_3")
     assert not sequence_3._is_consistent()  # Not a dag
+    assert 'The DAG of sequence "name_3" is not a directed acyclic graph' in caplog.text
 
     input_4 = InMemoryDataNode("foo", Scope.SCENARIO)
     output_4 = InMemoryDataNode("bar", Scope.SCENARIO)
@@ -164,9 +169,7 @@ def test_check_consistency():
     task_4_2 = Task("tbar", {}, print, [output_4], [input_4], TaskId("task_id_4_2"))
     sequence_4 = Sequence({}, [task_4_1, task_4_2], "name_4")
     assert not sequence_4._is_consistent()  # Not a Dag
-
-    class FakeDataNode:
-        config_id = "config_id_of_a_fake_dn"
+    assert 'The DAG of sequence "name_4" is not a directed acyclic graph' in caplog.text
 
     input_6 = DataNode("foo", Scope.SCENARIO, "input_id_5")
     output_6 = DataNode("bar", Scope.SCENARIO, "output_id_5")
@@ -174,6 +177,10 @@ def test_check_consistency():
     task_6_2 = Task("tbar", {}, print, [output_6], [FakeDataNode()], TaskId("task_id_5_2"))
     sequence_6 = Sequence({}, [task_6_1, task_6_2], "name_5")
     assert not sequence_6._is_consistent()  # Not a DataNode
+    assert (
+        'Invalid edge detected in sequence "name_5": left node Task "tbar" and right node FakeDataNode '
+        "must connect a Task and a DataNode" in caplog.text
+    )
 
     intermediate_7 = DataNode("foo", Scope.SCENARIO, "intermediate_id_7")
     output_7 = DataNode("bar", Scope.SCENARIO, "output_id_7")
@@ -197,6 +204,7 @@ def test_check_consistency():
     task_9_2 = Task("tbar", {}, print, [input_9_2], [output_9_2], TaskId("task_id_9_2"))
     sequence_9 = Sequence({}, [task_9_1, task_9_2], "name_9")
     assert not sequence_9._is_consistent()  # Not connected
+    assert 'The DAG of sequence "name_9" is not weakly connected' in caplog.text
 
     input_10_1 = DataNode("foo", Scope.SCENARIO, "output_id_10_1")
     intermediate_10_1 = DataNode("bar", Scope.SCENARIO, "intermediate_id_10_1")