# Testing Events: lifespan and startup - shutdown

When you need `lifespan` to run in your tests, you can use the `TestClient` with a `with` statement:

```python
from contextlib import asynccontextmanager

from fastapi import FastAPI
from fastapi.testclient import TestClient

items = {}


@asynccontextmanager
async def lifespan(app: FastAPI):
    items["foo"] = {"name": "Fighters"}
    items["bar"] = {"name": "Tenders"}
    yield
    # clean up items
    items.clear()


app = FastAPI(lifespan=lifespan)


@app.get("/items/{item_id}")
async def read_items(item_id: str):
    return items[item_id]


def test_read_items():
    # Before the lifespan starts, "items" is still empty
    assert items == {}

    with TestClient(app) as client:
        # Inside the "with TestClient" block, the lifespan starts and items added
        assert items == {"foo": {"name": "Fighters"}, "bar": {"name": "Tenders"}}

        response = client.get("/items/foo")
        assert response.status_code == 200
        assert response.json() == {"name": "Fighters"}

        # After the requests is done, the items are still there
        assert items == {"foo": {"name": "Fighters"}, "bar": {"name": "Tenders"}}

    # The end of the "with TestClient" block simulates terminating the app, so
    # the lifespan ends and items are cleaned up
    assert items == {}
```

You can read more details about the ["Running lifespan in tests in the official Starlette documentation site."](https://starlette.dev/lifespan/#running-lifespan-in-tests)

For the deprecated `startup` and `shutdown` events, you can use the `TestClient` as follows:

```python
from fastapi import FastAPI
from fastapi.testclient import TestClient

app = FastAPI()

items = {}


@app.on_event("startup")
async def startup_event():
    items["foo"] = {"name": "Fighters"}
    items["bar"] = {"name": "Tenders"}


@app.get("/items/{item_id}")
async def read_items(item_id: str):
    return items[item_id]


def test_read_items():
    with TestClient(app) as client:
        response = client.get("/items/foo")
        assert response.status_code == 200
        assert response.json() == {"name": "Fighters"}
```

## Related pages

- [About](./about-index.md)
- [Advanced User Guide](./advanced-user-guide-index.md)
- [Deployment](./deployment-index.md)
- [FastAPI](./fastapi-index.md)
- [FastAPI Docs](../index.md)
- [Features](./features-index.md)
- [How To - Recipes](./how-to-recipes-index.md)
- [Learn](./learn-index.md)
- [More](./more-index.md)
- [OpenAPI](./openapi-index.md)

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