* So, by using FastAPI you are saving development time, bugs, lines of code, and you would probably get the same performance (or better) you would if you didn't use it (as you would have to implement it all in your code)....

But here's the key point.

The security and dependency injection stuff is written once.

And you can make it as complex as you want. And still, have it written only once, in a single place. With all the flexibility.

But you can have thousands of endpoints (*path operations*) using the same security system.

# Define this here and not in the main mkdocs.yml file because that one is auto
# updated and written, and the script would remove the env var
INHERIT: !ENV [INSIDERS_FILE, '../en/mkdocs.no-insiders.yml']
markdown_extensions:
  pymdownx.highlight:

* ✊ 🆔.
* 🏗 📄 🆔 ⚪️➡️ ⚫️.
* 🤚 📄 ⏮️ 👈 🆔.
* 🚮 🎚 📄 `UserInDB` 🏷.

🏗 🔢 👈 🕴 💡 🤚 👆 👩‍💻 ⚪️➡️ `username` (⚖️ 🙆 🎏 🔢) 🔬 👆 *➡ 🛠️ 🔢*, 👆 💪 🌖 💪 🏤-⚙️ ⚫️ 💗 🍕 &amp; 🚮 <abbr title="Automated test, written in code, that checks if another piece of code is working correctly.">⚒ 💯</abbr> ⚫️:

```Python hl_lines="36-42"
{!../../../docs_src/nosql_databases/tutorial001.py!}
```

### Ⓜ-🎻

In this case, the original path `/app` would actually be served at `/api/v1/app`.

Even though all your code is written assuming there's just `/app`.

```Python hl_lines="6"
{!../../../docs_src/behind_a_proxy/tutorial001.py!}
```

次の章では、FastAPIアプリケーションをデプロイするための**具体的なレシピ**を紹介します。

しかし、今はこれらの重要な**コンセプトに基づくアイデア**を確認しましょう。これらのコンセプトは、他のどのタイプのWeb APIにも当てはまります。💡

## セキュリティ - HTTPS

<!-- NOTE: https.md written in Japanese does not exist, so it redirects to English one  -->
[前チャプターのHTTPSについて](https.md){.internal-link target=_blank}では、HTTPSがどのようにAPIを暗号化するのかについて学びました。

Many of the tutorials have blocks of code.

In most of the cases, these blocks of code are actual complete applications that can be run as is.

In fact, those blocks of code are not written inside the Markdown, they are Python files in the `./docs_src/` directory.

And those Python files are included/injected in the documentation when generating the site.

### Docs for tests

By creating a function that is only dedicated to getting your user from a `username` (or any other parameter) independent of your *path operation function*, you can more easily re-use it in multiple parts and also add <abbr title="Automated test, written in code, that checks if another piece of code is working correctly.">unit tests</abbr> for it:

```Python hl_lines="36-42"
{!../../../docs_src/nosql_databases/tutorial001.py!}
```

### f-strings

## External Courses

Although the [Tutorial - User Guide](../tutorial/index.md){.internal-link target=_blank} and this **Advanced User Guide** are written as a guided tutorial (like a book) and should be enough for you to **learn FastAPI**, you might want to complement it with additional courses.

    {!> ../../../docs_src/background_tasks/tutorial002.py!}
    ```

In this example, the messages will be written to the `log.txt` file *after* the response is sent.

If there was a query in the request, it will be written to the log in a background task.

And then another background task generated at the *path operation function* will write a message using the `email` path parameter.

## Technical Details