Better check for programmatic lightningignore

.github/workflows/ci-app-examples.yml

@@ -89,7 +89,8 @@ jobs:
       - name: Install Lightning package
         env:
           PACKAGE_NAME: ${{ matrix.pkg-name }}
-        run: pip install -e .
+        # do not use -e because it will make both packages available since it adds `src` to `sys.path` automatically
+        run: pip install .
 
       - name: Adjust tests
         if: ${{ matrix.pkg-name == 'lightning' }}

docs/source-app/levels/basic/hello_components/pl_multinode.py

@@ -10,7 +10,7 @@ def run(self):
         trainer = L.Trainer(max_epochs=10, strategy="ddp")
         trainer.fit(model)
 
-# 8 GPU: (2 nodes of 4 x v100)
+# 8 GPUs: (2 nodes of 4 x v100)
 component = LightningTrainerMultiNode(
     LightningTrainerDistributed,
     num_nodes=4,

examples/app_multi_node/train_lite.py

@@ -31,7 +31,7 @@ def run(self):
             optimizer.step()
 
 
-# Run over 2 nodes of 4 x V100
+# 8 GPUs: (2 nodes of 4 x v100)
 app = L.LightningApp(
     LiteMultiNode(
         LitePyTorchDistributed,

examples/app_multi_node/train_lt.py

@@ -11,10 +11,10 @@ def run(self):
         trainer.fit(model)
 
 
-# 8 GPU: (2 nodes of 4 x v100)
+# 8 GPUs: (2 nodes of 4 x v100)
 component = LightningTrainerMultiNode(
     LightningTrainerDistributed,
-    num_nodes=4,
+    num_nodes=2,
     cloud_compute=L.CloudCompute("gpu-fast-multi"),  # 4 x v100
 )
 app = L.LightningApp(component)

examples/app_multi_node/train_lt_script.py

@@ -2,11 +2,11 @@
 from lightning.app.components import LightningTrainerScript
 from lightning.app.utilities.packaging.cloud_compute import CloudCompute
 
-# Run over 2 nodes of 4 x V100
+# 8 GPUs: (2 nodes of 4 x v100)
 app = L.LightningApp(
     LightningTrainerScript(
         "pl_boring_script.py",
         num_nodes=2,
-        cloud_compute=CloudCompute("gpu-fast-multi"),
+        cloud_compute=CloudCompute("gpu-fast-multi"),  # 4 x v100
     ),
 )

examples/app_multi_node/train_pytorch.py

@@ -56,6 +56,6 @@ def run(self, main_address: str, main_port: int, num_nodes: int, node_rank: int)
 
 
 # 8 GPUs: (2 nodes x 4 v 100)
-compute = L.CloudCompute("gpu-fast-multi")  # 4xV100
+compute = L.CloudCompute("gpu-fast-multi")  # 4 x v100
 component = MultiNode(PyTorchDistributed, num_nodes=2, cloud_compute=compute)
 app = L.LightningApp(component)

examples/app_multi_node/train_pytorch_spawn.py

@@ -42,11 +42,11 @@ def run(
             optimizer.step()
 
 
-# Run over 2 nodes of 4 x V100
+# 8 GPUs: (2 nodes x 4 v 100)
 app = L.LightningApp(
     PyTorchSpawnMultiNode(
         PyTorchDistributed,
         num_nodes=2,
-        cloud_compute=L.CloudCompute("gpu-fast-multi"),  # 4 x V100
+        cloud_compute=L.CloudCompute("gpu-fast-multi"),  # 4 x v100
     )
 )

src/lightning_app/CHANGELOG.md

@@ -34,6 +34,10 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/).
 
 - Fixed the debugger detection mechanism for lightning App in VSCode ([#16068](https://github.com/Lightning-AI/lightning/pull/16068))
 
+
+- Fixed bug where components that are re-instantiated several times failed to initialize if they were modifying `self.lightningignore` ([#16080](https://github.com/Lightning-AI/lightning/pull/16080))
+
+
 - Fixed a bug where apps that had previously been deleted could not be run again from the CLI ([#16082](https://github.com/Lightning-AI/lightning/pull/16082))
 
 

src/lightning_app/cli/lightning_cli.py

@@ -358,8 +358,8 @@ def run_app(
     )
 
 
-if RequirementCache("lightning-lite"):
-    # lightning-lite may not be available when installing only standalone lightning-app package
+if RequirementCache("lightning-lite>=1.9.0.dev0") or RequirementCache("lightning>=1.9.0.dev0"):
+    # lightning.lite.cli may not be available when installing only standalone lightning-app package
     from lightning_lite.cli import _run_model
 
     run.add_command(_run_model)

src/lightning_app/core/flow.py

@@ -10,13 +10,7 @@
 from lightning_app.frontend import Frontend
 from lightning_app.storage import Path
 from lightning_app.storage.drive import _maybe_create_drive, Drive
-from lightning_app.utilities.app_helpers import (
-    _is_json_serializable,
-    _lightning_dispatched,
-    _LightningAppRef,
-    _set_child_name,
-    is_overridden,
-)
+from lightning_app.utilities.app_helpers import _is_json_serializable, _LightningAppRef, _set_child_name, is_overridden
 from lightning_app.utilities.component import _sanitize_state
 from lightning_app.utilities.exceptions import ExitAppException
 from lightning_app.utilities.introspection import _is_init_context, _is_run_context
@@ -325,7 +319,7 @@ def lightningignore(self) -> Tuple[str, ...]:
 
     @lightningignore.setter
     def lightningignore(self, lightningignore: Tuple[str, ...]) -> None:
-        if _lightning_dispatched():
+        if self._backend is not None:
             raise RuntimeError(
                 f"Your app has been already dispatched, so modifying the `{self.name}.lightningignore` does not have an"
                 " effect"

src/lightning_app/core/work.py

@@ -11,12 +11,7 @@
 from lightning_app.storage import Path
 from lightning_app.storage.drive import _maybe_create_drive, Drive
 from lightning_app.storage.payload import Payload
-from lightning_app.utilities.app_helpers import (
-    _is_json_serializable,
-    _lightning_dispatched,
-    _LightningAppRef,
-    is_overridden,
-)
+from lightning_app.utilities.app_helpers import _is_json_serializable, _LightningAppRef, is_overridden
 from lightning_app.utilities.component import _is_flow_context, _sanitize_state
 from lightning_app.utilities.enum import (
     CacheCallsKeys,
@@ -267,7 +262,7 @@ def lightningignore(self) -> Tuple[str, ...]:
 
     @lightningignore.setter
     def lightningignore(self, lightningignore: Tuple[str, ...]) -> None:
-        if _lightning_dispatched():
+        if self._backend is not None:
             raise RuntimeError(
                 f"Your app has been already dispatched, so modifying the `{self.name}.lightningignore` does not have an"
                 " effect"

tests/tests_app/components/multi_node/test_trainer.py

@@ -66,7 +66,7 @@ def test_trainer_run_executor_mps_forced_cpu(accelerator_given, accelerator_expe
         ({"strategy": "ddp_sharded_spawn"}, {"strategy": "ddp_sharded"}),
     ],
 )
-@pytest.mark.skipif(not module_available("pytorch"), reason="Lightning is not available")
+@pytest.mark.skipif(not module_available("torch"), reason="PyTorch is not available")
 def test_trainer_run_executor_arguments_choices(
     args_given: dict,
     args_expected: dict,

tests/tests_app/runners/test_cloud.py

@@ -1582,8 +1582,6 @@ def run(self):
 
 
 def test_programmatic_lightningignore(monkeypatch, caplog, tmpdir):
-    monkeypatch.setenv("LIGHTNING_DISPATCHED", "0")  # this is not cleaned up
-
     mock_client = mock.MagicMock()
     mock_client.projects_service_list_memberships.return_value = V1ListMembershipsResponse(
         memberships=[V1Membership(name="test-project", project_id="test-project-id")]
@@ -1650,8 +1648,6 @@ def run(self):
     assert "2 files were uploaded"  # a.txt and .lightningignore
     assert "files:\n5.0 MB: a.txt\nPerhaps" in caplog.text  # only this file appears
 
-    # replicate how the app would dispatch the app, and call `run`
-    monkeypatch.setenv("LIGHTNING_DISPATCHED", "1")
     flow.run()
 
 

tests/tests_examples_app/conftest.py

@@ -5,8 +5,8 @@
 
 import psutil
 import pytest
+from tests_examples_app.public import _PATH_EXAMPLES
 
-from lightning_app import _PROJECT_ROOT
 from lightning_app.storage.path import _storage_root_dir
 from lightning_app.utilities.component import _set_context
 from lightning_app.utilities.packaging import cloud_compute
@@ -24,11 +24,11 @@ def pytest_sessionstart(*_):
     """Pytest hook that get called after the Session object has been created and before performing collection and
     entering the run test loop."""
     for name, url in GITHUB_APP_URLS.items():
-        if not os.path.exists(os.path.join(_PROJECT_ROOT, "examples", name)):
-            path_examples = os.path.join(_PROJECT_ROOT, "examples")
-            Popen(["git", "clone", url, name], cwd=path_examples).wait(timeout=90)
+        app_path = _PATH_EXAMPLES / name
+        if not os.path.exists(app_path):
+            Popen(["git", "clone", url, name], cwd=_PATH_EXAMPLES).wait(timeout=90)
         else:
-            Popen(["git", "pull", "main"], cwd=os.path.join(_PROJECT_ROOT, "examples", name)).wait(timeout=90)
+            Popen(["git", "pull", "main"], cwd=app_path).wait(timeout=90)
 
 
 def pytest_sessionfinish(session, exitstatus):

tests/tests_examples_app/local/__init__.py

@@ -1,5 +1,3 @@
-import os
+from pathlib import Path
 
-from lightning_app import _PROJECT_ROOT
-
-_PATH_APPS = os.path.join(_PROJECT_ROOT, "tests", "tests_examples_app", "apps")
+_PATH_APPS = Path(__file__).resolve().parents[1] / "apps"

tests/tests_examples_app/public/__init__.py

@@ -1,5 +1,3 @@
-import os
+from pathlib import Path
 
-from lightning_app import _PROJECT_ROOT
-
-_PATH_EXAMPLES = os.path.join(_PROJECT_ROOT, "examples")
+_PATH_EXAMPLES = Path(__file__).resolve().parents[3] / "examples"

tests/tests_examples_app/public/test_multi_node.py

@@ -1,60 +1,47 @@
 import os
-import sys
 from unittest import mock
 
 import pytest
+from lightning_utilities.core.imports import package_available
 from tests_examples_app.public import _PATH_EXAMPLES
 
+from lightning_app.testing.helpers import _RunIf
 from lightning_app.testing.testing import application_testing, LightningTestApp
 
 
 class LightningTestMultiNodeApp(LightningTestApp):
     def on_before_run_once(self):
         res = super().on_before_run_once()
         if self.works and all(w.has_stopped for w in self.works):
-            assert len([w for w in self.works]) == 2
+            assert len(self.works) == 2
             return True
         return res
 
 
-@pytest.mark.skip(reason="flaky")
-@mock.patch("lightning_app.components.multi_node.base.is_running_in_cloud", return_value=True)
-def test_multi_node_example(_, monkeypatch):
-    monkeypatch.chdir(os.path.join(_PATH_EXAMPLES, "app_multi_node"))
-    command_line = [
-        "app.py",
-        "--blocking",
-        "False",
-        "--open-ui",
-        "False",
-    ]
-    result = application_testing(LightningTestMultiNodeApp, command_line)
-    assert result.exit_code == 0
-
-
-class LightningTestMultiNodeWorksApp(LightningTestApp):
-    def on_before_run_once(self):
-        res = super().on_before_run_once()
-        if self.works and all(w.has_stopped for w in self.works):
-            assert len([w for w in self.works]) == 2
-            return True
-        return res
+# for the skip to work, the package needs to be installed without editable mode
+_SKIP_LIGHTNING_UNAVAILABLE = pytest.mark.skipif(not package_available("lightning"), reason="script requires lightning")
 
 
 @pytest.mark.parametrize(
     "app_name",
     [
         "train_pytorch.py",
         "train_any.py",
-        # "app_lite_work.py",
         "train_pytorch_spawn.py",
-        # "app_pl_work.py": TODO Add once https://github.com/Lightning-AI/lightning/issues/15556 is resolved.
+        pytest.param("train_lite.py", marks=_SKIP_LIGHTNING_UNAVAILABLE),
+        pytest.param("train_lt_script.py", marks=_SKIP_LIGHTNING_UNAVAILABLE),
+        pytest.param("train_lt.py", marks=_SKIP_LIGHTNING_UNAVAILABLE),
     ],
 )
-@pytest.mark.skipif(sys.platform == "win32", reason="flaky")
+@_RunIf(skip_windows=True)  # flaky
 @mock.patch("lightning_app.components.multi_node.base.is_running_in_cloud", return_value=True)
 def test_multi_node_examples(_, app_name, monkeypatch):
+    # note: this test will fail locally:
+    # * if you installed `lightning_app`, then the examples need to be
+    #   rewritten to use `lightning_app` imports (CI does this)
+    # * if you installed `lightning`, then the imports in this file and mocks
+    #   need to be changed to use `lightning`.
     monkeypatch.chdir(os.path.join(_PATH_EXAMPLES, "app_multi_node"))
     command_line = [app_name, "--blocking", "False", "--open-ui", "False", "--setup"]
-    result = application_testing(LightningTestMultiNodeWorksApp, command_line)
+    result = application_testing(LightningTestMultiNodeApp, command_line)
     assert result.exit_code == 0