## Proxy with a stripped path prefix

Having a proxy with a stripped path prefix, in this case, means that you could declare a path at `/app` in your code, but then, you add a layer on top (the proxy) that would put your **FastAPI** application under a path like `/api/v1`.

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`.

#### "Schema"

A "schema" is a definition or description of something. Not the code that implements it, but just an abstract description.

#### API "schema"

In this case, <a href="https://github.com/OAI/OpenAPI-Specification" class="external-link" target="_blank">OpenAPI</a> is a specification that dictates how to define a schema of your API.

Of course, there are some cases where there's no problem in running the previous steps multiple times, in that case, it's a lot easier to handle.

!!! tip
    Also, keep in mind that depending on your setup, in some cases you **might not even need any previous steps** before starting your application.

    In that case, you wouldn't have to worry about any of this. 🤷

### Examples of Previous Steps Strategies

In this case, you could want to document how that external API *should* look like. What *path operation* it should have, what body it should expect, what response it should return, etc.

## An app with callbacks

In this case, if you had **multiple containers**, by default, when Prometheus came to **read the metrics**, it would get the ones for **a single container each time** (for the container that handled that particular request), instead of getting the **accumulated metrics** for all the replicated containers.

* ✏️ Fix typo in `fastapi/routing.py` . PR [#10520](https://github.com/tiangolo/fastapi/pull/10520) by [@sepsh](https://github.com/sepsh).
* 📝 Replace HTTP code returned in case of existing user error in docs for testing. PR [#4482](https://github.com/tiangolo/fastapi/pull/4482) by [@TristanMarion](https://github.com/TristanMarion).

    * As the `q` parameter is declared with `= None`, it is optional.
    * Without the `None` it would be required (as is the body in the case with `PUT`).
* For `PUT` requests to `/items/{item_id}`, Read the body as JSON:
    * Check that it has a required attribute `name` that should be a `str`.

  - help-fastapi.md
  - contributing.md
- release-notes.md
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* 100% <abbr title="The amount of code that is automatically tested">test coverage</abbr>.
* 100% <abbr title="Python type annotations, with this your editor and external tools can give you better support">type annotated</abbr> code base.
* Used in production applications.

## Starlette features

!!! tip
    If you want something quick to copy and paste, don't use this example, use the last one below.

Then, when you create an instance of that `Settings` class (in this case, in the `settings` object), Pydantic will read the environment variables in a case-insensitive way, so, an upper-case variable `APP_NAME` will still be read for the attribute `app_name`.