Step 4: Implement tests for the File Server component with pytest¶
Let’s create a simple App with our File Server and File Server Test components.
Once the File Server is up and running, we’ll execute the test_file_server LightningWork and when both calls are successful, we exit the App using self._exit.
from lightning import LightningApp, LightningFlow
class Flow(LightningFlow):
def __init__(self):
super().__init__()
# 1: Create a drive to share data between works
self.drive = Drive("lit://file_server")
# 2: Create the filer server
self.file_server = FileServer(self.drive)
# 3: Create the file ser
self.test_file_server = TestFileServer(self.drive)
def run(self):
# 1: Start the file server.
self.file_server.run()
# 2: Trigger the test file server work when ready.
if self.file_server.alive():
# 3 Execute the test file server work.
self.test_file_server.run(self.file_server.url)
self.test_file_server.run(self.file_server.url, first=False)
# 4 When both execution are successful, exit the app.
if self.test_file_server.num_successes == 2:
self.stop()
def configure_layout(self):
# Expose the file_server component
# in the UI using its `/` endpoint.
return {"name": "File Server", "content": self.file_server}
Simply create a test.py file with the following code and run pytest tests.py:
def test_file_server():
app = LightningApp(Flow())
MultiProcessRuntime(app).dispatch()
To test the App in the cloud, create a cloud_test.py file with the following code and run pytest cloud_test.py.
Under the hood, we are using the end-to-end testing playwright library, so you can interact with the UI.
def test_file_server_in_cloud():
# You need to provide the directory containing the app file.
app_dir = "docs/source-app/examples/file_server"
with run_app_in_cloud(app_dir) as (admin_page, view_page, get_logs_fn, name):
"""# 1. `admin_page` and `view_page` are playwright Page Objects.
# Check out https://playwright.dev/python/ doc to learn more.
# You can click the UI and trigger actions.
# 2. By calling logs = get_logs_fn(),
# you get all the logs currently on the admin page.
"""
Test the application¶
Clone the Lightning repo and run the following command:
pytest docs/source/examples/file_server/app.py --capture=no -v
Tutorial¶
Find more examples¶
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