* Security and authentication, including support for **OAuth2** with **JWT tokens** and **HTTP Basic** auth.
* More advanced (but equally easy) techniques for declaring **deeply nested JSON models** (thanks to Pydantic).
* **GraphQL** integration with <a href="https://strawberry.rocks" class="external-link" target="_blank">Strawberry</a> and other libraries.

def read_user(user_id: int, db: Session = Depends(get_db)):
    db_user = crud.get_user(db, user_id=user_id)
    ...
```

/// info

🚥 👆 💪 🔗 👆 🔗 💽 🔁, 👀 [🔁 🗄 (🔗) 💽](../advanced/async-sql-databases.md){.internal-link target=_blank}.

///

/// note | "📶 📡 ℹ"

🚥 👆 😟 & ✔️ ⏬ 📡 💡, 👆 💪 ✅ 📶 📡 ℹ ❔ 👉 `async def` 🆚 `def` 🍵 [🔁](../async.md#i_2){.internal-link target=_blank} 🩺.

Attribution 4.0 International

=======================================================================

Creative Commons Corporation ("Creative Commons") is not a law firm and
does not provide legal services or legal advice. Distribution of
Creative Commons public licenses does not create a lawyer-client or
other relationship. Creative Commons makes its licenses and related
information available on an "as-is" basis. Creative Commons gives no

    Read more about it in the
    [FastAPI docs for Security](https://fastapi.tiangolo.com/tutorial/security/) and
    in the
    [FastAPI docs for OAuth2 scopes](https://fastapi.tiangolo.com/advanced/security/oauth2-scopes/).

    **Example**

    ```python
    from typing import Annotated

    from fastapi import Security, FastAPI

    from .db import User

      return false;
    }

    private void checkModCount() {
      if (modCount != expectedModCount) {
        throw new ConcurrentModificationException();
      }
    }

    /**
     * Advances nextCursor to the index of the first element after {@code c} that is not in {@code
     * skipMe} and returns {@code size()} if there is no such element.
     */
    private void nextNotInSkipMe(int c) {

⛔️ **Shell** form:

```Dockerfile
# ⛔️ Don't do this
CMD fastapi run app/main.py --port 80
```

Make sure to always use the **exec** form to ensure that FastAPI can shutdown gracefully and [lifespan events](../advanced/events.md){.internal-link target=_blank} are triggered.

 * equals</i>. That is, {@code a.compareTo(b)} or {@code comparator.compare(a, b)} should equal zero
 * <i>if and only if</i> {@code a.equals(b)}. If this advice is not followed, the resulting
 * collection will not correctly obey its specification.
 *
 * <p>See the Guava User Guide article on <a href=

_2019-04-10_

 *  Fix: Don't crash when an interceptor retries when there are no more routes. This was an
    edge-case regression introduced with the events cleanup in 3.14.0.

 *  Fix: Provide actionable advice when the exchange is non-null. Prior to 3.14, OkHttp would
    silently leak connections when an interceptor retries without closing the response body. With
    3.14 we detect this problem but the exception was not helpful.

 * <i>deprecate</i> this class.
 *
 * <p>Many replacements involve adopting {@code Stream}, and these changes can sometimes make your
 * code verbose. Whenever following this advice, you should check whether {@code Stream} could be
 * adopted more comprehensively in your code; the end result may be quite a bit simpler.
 *
 * <h3>See also</h3>
 *
 * <p>See the Guava User Guide article on <a href=

   * Creates an {@code ArrayList} instance to hold {@code estimatedSize} elements, <i>plus</i> an
   * unspecified amount of padding; you almost certainly mean to call {@link
   * #newArrayListWithCapacity} (see that method for further advice on usage).
   *
   * <p><b>Note:</b> This method will soon be deprecated. Even in the rare case that you do want
   * some amount of padding, it's best if you choose your desired amount explicitly.
   *