## Embed a single body parameter

Let's say you only have a single `item` body parameter from a Pydantic model `Item`.

By default, **FastAPI** will then expect its body directly.

But if you want it to expect a JSON with a key `item` and inside of it the model contents, as it does when you declare extra body parameters, you can use the special `Body` parameter `embed`:

```Python

```JSON
{
    "message": "Hello World",
    "root_path": "/api/v1"
}
```

So, it won't expect to be accessed at `http://127.0.0.1:8000/api/v1/app`.

Uvicorn will expect the proxy to access Uvicorn at `http://127.0.0.1:8000/app`, and then it would be the proxy's responsibility to add the extra `/api/v1` prefix on top.

title: "\U0001F649"
labels: ''
assignees: ''

---

🛑 𝙎𝙏𝙊𝙋

This issue tracker is not the place for questions!

If you want to ask how to do something, or to understand why something isn't working the way you expect it to, use Stack Overflow. https://stackoverflow.com/questions/tagged/okhttp

            shouldDeduplicateBuiltInSymbols = false,

            // Because the file to compile may be contained in a "common" multiplatform module, an `expect` declaration doesn't necessarily
            // have an obvious associated `actual` symbol. `shouldStubOrphanedExpectSymbols` generates stubs for such `expect` declarations.
            shouldStubOrphanedExpectSymbols = true,

    Approximately 10MB is required for the Maven installation itself. In addition to
    that, additional disk space will be used for your local Maven repository. The size
    of your local repository will vary depending on usage but expect at least 500MB.
  Operating System:
    Windows:
      Windows 2000 or above.
    Unix based systems (Linux, Solaris and Mac OS X) and others:
      No minimum requirement.

  Installing Maven
  ----------------

And you can declare some of the files as `bytes` and some as `UploadFile`.

!!! warning
    You can declare multiple `File` and `Form` parameters in a *path operation*, but you can't also declare `Body` fields that you expect to receive as JSON, as the request will have the body encoded using `multipart/form-data` instead of `application/json`.

    This is not a limitation of **FastAPI**, it's part of the HTTP protocol.

## Recap

Otherwise, when filing an issue, make sure to answer these five questions:

1. What version of Go are you using (`go version`)?
2. What operating system and processor architecture are you using?
3. What did you do?
4. What did you expect to see?
5. What did you see instead?

For change proposals, see [Proposing Changes To Go](https://go.dev/s/proposal-process).

## Contributing code

A middleware doesn't have to be made for FastAPI or Starlette to work, as long as it follows the ASGI spec.

In general, ASGI middlewares are classes that expect to receive an ASGI app as the first argument.

So, in the documentation for third-party ASGI middlewares they will probably tell you to do something like:

```Python
from unicorn import UnicornMiddleware

            // Because the file to compile may be contained in a "common" multiplatform module, an `expect` declaration doesn't necessarily
            // have an obvious associated `actual` symbol. `shouldStubOrphanedExpectSymbols` generates stubs for such `expect` declarations.
            shouldStubOrphanedExpectSymbols = true,

        // If there's a "Expect: 100-continue" header on the request, wait for a "HTTP/1.1 100
        // Continue" response before transmitting the request body. If we don't get that, return
        // what we did get (such as a 4xx response) without ever transmitting the request body.
        if ("100-continue".equals(request.header("Expect"), ignoreCase = true)) {
          exchange.flushRequest()