* Automatic data model documentation with <a href="https://json-schema.org/" class="external-link" target="_blank"><strong>JSON Schema</strong></a> (as OpenAPI itself is based on JSON Schema).
* Designed around these standards, after a meticulous study. Instead of an afterthought layer on top.
* This also allows using automatic **client code generation** in many languages.

### Automatic docs

Using `UploadFile` has several advantages over `bytes`:

* You don't have to use `File()` in the default value of the parameter.
* It uses a "spooled" file:
    * A file stored in memory up to a maximum size limit, and after passing this limit it will be stored in disk.
* This means that it will work well for large files like images, videos, large binaries, etc. without consuming all the memory.
* You can get metadata from the uploaded file.

```

🤙 👉 📋 🔢:

```
John Doe
```

🔢 🔨 📄:

* ✊ `first_name` & `last_name`.
* 🗜 🥇 🔤 🔠 1️⃣ ↖ 💼 ⏮️ `title()`.
* <abbr title="Puts them together, as one. With the contents of one after the other.">🔢</abbr> 👫 ⏮️ 🚀 🖕.

```Python hl_lines="2"
{!../../../docs_src/python_types/tutorial001.py!}
```

### ✍ ⚫️

⚫️ 📶 🙅 📋.

✋️ 🔜 🌈 👈 👆 ✍ ⚫️ ⚪️➡️ 🖌.

fern-banner.svg...

* `^`: starts with the following characters, doesn't have characters before.
* `fixedquery`: has the exact value `fixedquery`.
* `$`: ends there, doesn't have any more characters after `fixedquery`.

If you feel lost with all these **"regular expression"** ideas, don't worry. They are a hard topic for many people. You can still do a lot of stuff without needing regular expressions yet.

        <img class="sponsor-image" src="/img/sponsors/cryptapi-banner.svg" />
      </a>
    </div>
    <div class="item">
      <a title="Build, run and scale your apps on a modern, reliable, and secure PaaS." style="display: block; position: relative;" href="https://platform.sh/try-it-now/?utm_source=fastapi-signup&utm_medium=banner&utm_campaign=FastAPI-signup-June-2023" target="_blank">

    end_datetime: datetime = Body(),
    process_after: timedelta = Body(),
    repeat_at: time | None = Body(default=None),
):
    start_process = start_datetime + process_after
    duration = end_datetime - start_process
    return {
        "item_id": item_id,
        "start_datetime": start_datetime,
        "end_datetime": end_datetime,
        "process_after": process_after,
        "repeat_at": repeat_at,

这表明了他们对 FastAPI 及其**社区**（您）的真正承诺，因为他们不仅想为您提供**良好的服务**，而且还想确保您拥有一个**良好且健康的框架**：FastAPI。 🙇

您可能想尝试他们的服务并阅读他们的指南：

* <a href="https://docs.platform.sh/languages/python.html?utm_source=fastapi-signup&utm_medium=banner&utm_campaign=FastAPI-signup-June-2023" class="external-link" target="_blank" >Platform.sh</a>

def use_route_names_as_operation_ids(app: FastAPI) -> None:
    """
    Simplify operation IDs so that generated API clients have simpler function
    names.

    Should be called only after all routes have been added.
    """
    for route in app.routes:
        if isinstance(route, APIRoute):
            route.operation_id = route.name  # in this case, 'read_items'

    cwd = os.getcwd()
    os.chdir(tmp_path)
    test_db = Path("./test.db")
    if test_db.is_file():  # pragma: nocover
        test_db.unlink()
    # Import while creating the client to create the DB after starting the test session
    from docs_src.sql_databases.sql_app.tests import test_sql_app

    # Ensure import side effects are re-executed
    importlib.reload(test_sql_app)
    test_sql_app.test_create_user()