///

## Order the parameters as you need { #order-the-parameters-as-you-need }

/// tip

This is probably not as important or necessary if you use `Annotated`.

///

Let's say that you want to declare the query parameter `q` as a required `str`.

And you don't need to declare anything else for that parameter, so you don't really need to use `Query`.

OdHOim9+
-----END PRIVATE KEY-----
```

Recommendations
---------------

Typically servers need a held certificate plus a chain of intermediates. Servers only need the
private key for their own certificate. The chain served by a server doesn't need the root
certificate.

The trusted roots don't need to be the same for client and server when using client authentication.

## Consequences

* We are incurring debt that will need to be paid later via deprecations or breaking changes to existing classes. The implementation for some Gradle types will be more complicated than an equivalent clean-sheet implementation.
* During code reviews that introduce new APIs, reviewers need to be mindful that all new properties are implemented with lazy types.

@deprecated(
    "UJSONResponse is deprecated, FastAPI now serializes data directly to JSON "
    "bytes via Pydantic when a return type or response model is set, which is "
    "faster and doesn't need a custom response class. Read more in the FastAPI "
    "docs: https://fastapi.tiangolo.com/advanced/custom-response/#orjson-or-response-model "
    "and https://fastapi.tiangolo.com/tutorial/response-model/",

    own the intellectual property, then you'll need to sign an [individual
    CLA][]. Please include your GitHub username.
  - If you work for a company that wants to allow you to contribute your work,
    then you'll need to sign a [corporate CLA][].

You generally only need to submit a CLA once, so if you've already submitted
one (even if it was for a different project), you probably don't need to do it
again.

You can see more details in [Starlette's official docs for Background Tasks](https://www.starlette.dev/background/).

## Caveat { #caveat }

If you need to perform heavy background computation and you don't necessarily need it to be run by the same process (for example, you don't need to share memory, variables, etc), you might benefit from using other bigger tools like [Celery](https://docs.celeryq.dev).

Up to now, you have been declaring the parts of the request that you need with their types.

Taking data from:

* The path as parameters.
* Headers.
* Cookies.
* etc.

And by doing so, **FastAPI** is validating that data, converting it and generating documentation for your API automatically.

But there are situations where you might need to access the `Request` object directly.

Doing this provides the following specific benefits:
- **Reduce the API surface** - We no longer need to maintain two methods.
- **Consistency** - All languages have consistent access to the same APIs and ergonomics in the DSL.
- **Reduce the size of the Gradle distribution** - We no longer need to carry multiple standard libraries for different languages.

## Decision

# JSON Compatible Encoder { #json-compatible-encoder }

There are some cases where you might need to convert a data type (like a Pydantic model) to something compatible with JSON (like a `dict`, `list`, etc).

For example, if you need to store it in a database.

For that, **FastAPI** provides a `jsonable_encoder()` function.

## Using the `jsonable_encoder` { #using-the-jsonable-encoder }

# Response - Change Status Code { #response-change-status-code }

You probably read before that you can set a default [Response Status Code](../tutorial/response-status-code.md).

But in some cases you need to return a different status code than the default.

## Use case { #use-case }

For example, imagine that you want to return an HTTP status code of "OK" `200` by default.