Add integration tests for frontend_path redirects

Test on_load and on_mount redirects with and without a frontend_path
prefix in both dev mode (AppHarness) and prod mode (AppHarnessProd).

See #5674

Author: tartansandal

tests/integration/tests_playwright/test_frontend_path.py

@@ -0,0 +1,282 @@
+import os
+from collections.abc import Generator
+
+import pytest
+from playwright.sync_api import Page, expect
+
+from reflex.testing import AppHarness, AppHarnessProd
+
+
+def OnLoadRedirectApp():
+    """App to demonstrate an on_load redirection issue.
+
+    See https://github.com/reflex-dev/reflex/issues/5674 for details.
+    """
+    import reflex as rx
+
+    @rx.page("/")
+    def index():
+        return rx.container(
+            rx.input(
+                value=rx.State.router.session.client_token,
+                read_only=True,
+                id="token",
+            ),
+            rx.vstack(
+                rx.heading("This is the index page!"),
+                rx.button("Go to Subpage!", on_click=rx.redirect("/subpage")),
+            ),
+        )
+
+    @rx.page("/subpage")
+    def subpage():
+        return rx.container(
+            rx.vstack(
+                rx.heading("This is the sub page!"),
+                rx.button("Go to index!", on_click=rx.redirect("/")),
+                rx.button("Bounce to index!", on_click=rx.redirect("/bouncer")),
+            )
+        )
+
+    @rx.page("/bouncer", on_load=rx.redirect("/"))
+    def bouncer():
+        return rx.container(
+            rx.vstack(
+                rx.heading("This is the bouncer page!"),
+                rx.text("You should not be here!"),
+                rx.button("Go to index!", on_click=rx.redirect("/")),
+            ),
+        )
+
+    app = rx.App()  # noqa: F841
+
+
+@pytest.fixture
+def onload_redirect_app(tmp_path) -> Generator[AppHarness, None, None]:
+    """Start the OnLoadRedirectApp in prod mode without a frontend_path.
+
+    Baseline to show on_load redirects work without a frontend_path.
+
+    Args:
+        tmp_path: pytest tmp_path fixture
+
+    Yields:
+        running AppHarness instance
+    """
+    with AppHarnessProd.create(
+        root=tmp_path / "onload_redirect_app",
+        app_source=OnLoadRedirectApp,
+    ) as harness:
+        assert harness.app_instance is not None, "app is not running"
+        yield harness
+
+
+@pytest.fixture
+def onload_redirect_with_prefix_app_dev(tmp_path) -> Generator[AppHarness, None, None]:
+    """Start the OnLoadRedirectApp in dev mode with frontend_path set to /prefix.
+
+    Args:
+        tmp_path: pytest tmp_path fixture
+
+    Yields:
+        running AppHarness instance
+    """
+    os.environ["REFLEX_FRONTEND_PATH"] = "/prefix"
+    try:
+        with AppHarness.create(
+            root=tmp_path / "onload_redirect_with_prefix_app_dev",
+            app_source=OnLoadRedirectApp,
+        ) as harness:
+            assert harness.app_instance is not None, "app is not running"
+            yield harness
+    finally:
+        os.environ.pop("REFLEX_FRONTEND_PATH", None)
+
+
+@pytest.fixture
+def onload_redirect_with_prefix_app_prod(
+    tmp_path,
+) -> Generator[AppHarness, None, None]:
+    """Start the OnLoadRedirectApp in prod mode with frontend_path set to /prefix.
+
+    Args:
+        tmp_path: pytest tmp_path fixture
+
+    Yields:
+        running AppHarness instance
+    """
+    os.environ["REFLEX_FRONTEND_PATH"] = "/prefix"
+    try:
+        with AppHarnessProd.create(
+            root=tmp_path / "onload_redirect_with_prefix_app_prod",
+            app_source=OnLoadRedirectApp,
+        ) as harness:
+            assert harness.app_instance is not None, "app is not running"
+            yield harness
+    finally:
+        os.environ.pop("REFLEX_FRONTEND_PATH", None)
+
+
+def OnMountRedirectApp():
+    """App to demonstrate on_mount redirection behaviour."""
+    import reflex as rx
+
+    @rx.page("/")
+    def index():
+        return rx.container(
+            rx.input(
+                value=rx.State.router.session.client_token,
+                read_only=True,
+                id="token",
+            ),
+            rx.vstack(
+                rx.heading("This is the index page!"),
+                rx.button("Go to Subpage!", on_click=rx.redirect("/subpage")),
+            ),
+        )
+
+    @rx.page("/subpage")
+    def subpage():
+        return rx.container(
+            rx.vstack(
+                rx.heading("This is the sub page!"),
+                rx.button("Go to index!", on_click=rx.redirect("/")),
+                rx.button("Bounce to index!", on_click=rx.redirect("/bouncer")),
+            )
+        )
+
+    @rx.page("/bouncer")
+    def bouncer():
+        return rx.container(
+            rx.vstack(
+                rx.heading("This is the bouncer page!"),
+                rx.text("You should not be here!"),
+                rx.spinner("Go to index!", on_mount=rx.redirect("/")),
+            ),
+        )
+
+    app = rx.App()  # noqa: F841
+
+
+@pytest.fixture
+def onmount_redirect_app(tmp_path) -> Generator[AppHarness, None, None]:
+    """Start the OnMountRedirectApp in prod mode without a frontend_path.
+
+    Baseline to show on_mount redirects work without a frontend_path.
+
+    Args:
+        tmp_path: pytest tmp_path fixture
+
+    Yields:
+        running AppHarness instance
+    """
+    with AppHarnessProd.create(
+        root=tmp_path / "onmount_redirect_app",
+        app_source=OnMountRedirectApp,
+    ) as harness:
+        assert harness.app_instance is not None, "app is not running"
+        yield harness
+
+
+@pytest.fixture
+def onmount_redirect_with_prefix_app_dev(
+    tmp_path,
+) -> Generator[AppHarness, None, None]:
+    """Start the OnMountRedirectApp in dev mode with frontend_path set to /prefix.
+
+    Args:
+        tmp_path: pytest tmp_path fixture
+
+    Yields:
+        running AppHarness instance
+    """
+    os.environ["REFLEX_FRONTEND_PATH"] = "/prefix"
+    try:
+        with AppHarness.create(
+            root=tmp_path / "onmount_redirect_with_prefix_app_dev",
+            app_source=OnMountRedirectApp,
+        ) as harness:
+            assert harness.app_instance is not None, "app is not running"
+            yield harness
+    finally:
+        os.environ.pop("REFLEX_FRONTEND_PATH", None)
+
+
+@pytest.fixture
+def onmount_redirect_with_prefix_app_prod(
+    tmp_path,
+) -> Generator[AppHarness, None, None]:
+    """Start the OnMountRedirectApp in prod mode with frontend_path set to /prefix.
+
+    Args:
+        tmp_path: pytest tmp_path fixture
+
+    Yields:
+        running AppHarness instance
+    """
+    os.environ["REFLEX_FRONTEND_PATH"] = "/prefix"
+    try:
+        with AppHarnessProd.create(
+            root=tmp_path / "onmount_redirect_with_prefix_app_prod",
+            app_source=OnMountRedirectApp,
+        ) as harness:
+            assert harness.app_instance is not None, "app is not running"
+            yield harness
+    finally:
+        os.environ.pop("REFLEX_FRONTEND_PATH", None)
+
+
+@pytest.mark.ignore_console_error
+@pytest.mark.parametrize(
+    ("app_fixture_name", "frontend_path"),
+    [
+        ("onload_redirect_app", ""),
+        ("onload_redirect_with_prefix_app_dev", "/prefix"),
+        ("onload_redirect_with_prefix_app_prod", "/prefix"),
+        ("onmount_redirect_app", ""),
+        ("onmount_redirect_with_prefix_app_dev", "/prefix"),
+        ("onmount_redirect_with_prefix_app_prod", "/prefix"),
+    ],
+)
+def test_redirection_triggers(
+    app_fixture_name: str, frontend_path: str, page: Page, request
+):
+    """Ensure that on_load and on_mount redirects work with/without a frontend_path.
+
+    Tests both dev mode (AppHarness) and prod mode (AppHarnessProd) to cover
+    the bug reported in https://github.com/reflex-dev/reflex/issues/5674,
+    where redirects from on_load and on_mount handlers were lost when serving
+    from a non-root frontend path.
+
+    Args:
+        app_fixture_name: Name of the app fixture to use for the test.
+        frontend_path: The frontend_path used by the app fixture.
+        page: Playwright Page object to interact with the app.
+        request: Pytest request object to access fixtures.
+    """
+    app_fixture = request.getfixturevalue(app_fixture_name)
+    assert app_fixture.frontend_url is not None
+
+    base_url = app_fixture.frontend_url.rstrip("/")
+    base_url += frontend_path
+    page.goto(f"{base_url}/")
+    expect(page.get_by_text("This is the index page!")).to_be_visible()
+
+    # Go to /subpage
+    page.get_by_role("button", name="Go to Subpage!").click()
+    expect(page.get_by_text("This is the sub page!")).to_be_visible()
+    expect(page).to_have_url(f"{base_url}/subpage")
+
+    # Click "Bounce to index!" (should redirect to index via on_load/on_mount)
+    page.get_by_role("button", name="Bounce to index!").click()
+    expect(page.get_by_text("This is the index page!")).to_be_visible()
+    expect(page).to_have_url(f"{base_url}/")
+
+    # Directly navigate to /bouncer/ and verify redirect
+    page.goto(f"{base_url}/bouncer/")
+    expect(page.get_by_text("This is the index page!")).to_be_visible()
+
+    # Check that 404's work and do not change the url
+    page.goto(f"{base_url}/not-a-page")
+    expect(page.get_by_text("404: Page not found")).to_be_visible()
+    expect(page).to_have_url(f"{base_url}/not-a-page")