You could use these tools and ideas if you are setting up **your own deployment system** while taking care of the other deployment concepts yourself.

But first, let's check some small concepts.

## In a hurry?

If you don't care about any of these terms and you just need to add security with authentication based on username and password *right now*, skip to the next chapters.

## OAuth2

OAuth2 is a specification that defines several ways to handle authentication and authorization.

It is quite an extensive specification and covers several complex use cases.

Having another process manager inside the container (as would be with Gunicorn or Uvicorn managing Uvicorn workers) would only add **unnecessary complexity** that you are most probably already taking care of with your cluster system.

### Containers with Multiple Processes and Special Cases

Of course, there are **special cases** where you could want to have **a container** with a **Gunicorn process manager** starting several **Uvicorn worker processes** inside.

So, all these are different origins:

* `http://localhost`
* `https://localhost`
* `http://localhost:8080`

Even if they are all in `localhost`, they use different protocols or ports, so, they are different "origins".

## Steps

!!! info
    In Pydantic version 1 the method to get the JSON Schema for a model was called `Item.schema()`, in Pydantic version 2, the method is called `Item.model_json_schema()`.

Nevertheless, although we are not using the default integrated functionality, we are still using a Pydantic model to manually generate the JSON Schema for the data that we want to receive in YAML.

                have their default values. This is different from
                `response_model_exclude_defaults` in that if the fields are set,
                they will be included in the response, even if the value is the same
                as the default.

                When `True`, default values are omitted from the response.

                Read more about it in the

    When you return a `Response` directly, like in the example above, it will be returned directly.

    It won't be serialized with a model, etc.

    Make sure it has the data you want it to have, and that the values are valid JSON (if you are using `JSONResponse`).

!!! note "Technical Details"
    You could also use `from starlette.responses import JSONResponse`.

But you still need to define what is the dependable, the callable that you pass as a parameter to `Depends()` or `Security()`.

There are multiple tools that you can use to create those dependables, and they get integrated into OpenAPI so they are shown in the automatic docs UI, they can be used by automatically generated clients and SDKs, etc.

You can import them from `fastapi.security`:

```python

## Technical Details

!!! tip
    If you are already using **FastAPI** version **0.99.0 or above**, you can probably **skip** these details.

    They are more relevant for older versions, before OpenAPI 3.1.0 was available.

    You can consider this a brief OpenAPI and JSON Schema **history lesson**. 🤓

!!! warning
    These are very technical details about the standards **JSON Schema** and **OpenAPI**.

# Learn

Here are the introductory sections and the tutorials to learn **FastAPI**.