from fastapi import FastAPI, Request

app = FastAPI()


@app.get("/items/{item_id}")
def read_root(item_id: str, request: Request):
    client_host = request.client.host

<div style="text-align: right; margin-right: 10%;">Brian Okken - <strong><a href="https://pythonbytes.fm/episodes/show/123/time-to-right-the-py-wrongs?time_in_sec=855" target="_blank">Python Bytes</a> podcast host</strong> <a href="https://twitter.com/brianokken/status/1112220079972728832" target="_blank"><small>(ref)</small></a></div>

---

所以，下面这部分代码才会运行：

```Python
    uvicorn.run(app, host="0.0.0.0", port=8000)
```

---

如果你是导入这个模块（文件）就不会这样。

因此，如果你的另一个文件 `importer.py` 像这样：

```Python
from myapp import app

# Some more code
```

在这种情况下，`myapp.py` 内部的自动变量不会有值为 `"__main__"` 的变量 `__name__`。

所以，下面这一行不会被执行：

```Python
    uvicorn.run(app, host="0.0.0.0", port=8000)
```

!!! info

```

## `TrustedHostMiddleware`

Erzwingt, dass alle eingehenden Requests einen korrekt gesetzten `Host`-Header haben, um sich vor HTTP-Host-Header-Angriffen zu schützen.

```Python hl_lines="2  6-8"
{!../../../docs_src/advanced_middleware/tutorial002.py!}
```

Die folgenden Argumente werden unterstützt:

<div style="text-align: right; margin-right: 10%;">Brian Okken - <strong><a href="https://pythonbytes.fm/episodes/show/123/time-to-right-the-py-wrongs?time_in_sec=855" target="_blank">Python Bytes</a> podcast host</strong> <a href="https://twitter.com/brianokken/status/1112220079972728832" target="_blank"><small>(ref)</small></a></div>

---

```

</div>

then the internal variable `__name__` in your file, created automatically by Python, will have as value the string `"__main__"`.

So, the section:

```Python
    uvicorn.run(app, host="0.0.0.0", port=8000)
```

will run.

---

This won't happen if you import that module (file).

So, if you have another file `importer.py` with:

```Python
from myapp import app

RUN pip install --no-cache-dir --upgrade -r /code/requirements.txt

COPY ./app /code/app

CMD ["uvicorn", "app.main:app", "--host", "0.0.0.0", "--port", "80"]

# If running behind a proxy like Nginx or Traefik add --proxy-headers
# CMD ["uvicorn", "app.main:app", "--host", "0.0.0.0", "--port", "80", "--proxy-headers"]
```

</details>

## 什么是容器

RUN pip install --no-cache-dir --upgrade -r /code/requirements.txt

COPY ./app /code/app

CMD ["uvicorn", "app.main:app", "--host", "0.0.0.0", "--port", "80"]

# If running behind a proxy like Nginx or Traefik add --proxy-headers
# CMD ["uvicorn", "app.main:app", "--host", "0.0.0.0", "--port", "80", "--proxy-headers"]
```

</details>

## O que é um Contêiner

なので、以下:

```Python
    uvicorn.run(app, host="0.0.0.0", port=8000)
```

は実行されます。

---

そのモジュール (ファイル) をインポートした場合は、こうはなりません。

したがって、次のようなもう一つのファイル `importer.py` がある場合:

```Python
from myapp import app

# Some more code
```

`myapp.py` 内の自動変数には、値が `"__main __"` の変数 `__name__` はありません。

したがって、以下の行:

```Python
    uvicorn.run(app, host="0.0.0.0", port=8000)
```

は実行されません。

* Tự động tài liệu hóa data model theo <a href="https://json-schema.org/" class="external-link" target="_blank"><strong>JSON Schema</strong></a> (OpenAPI bản thân...