- deployment/docker.md
  - How To - Recipes:
    - how-to/index.md
    - how-to/general.md
    - how-to/graphql.md
    - how-to/custom-request-and-route.md
    - how-to/conditional-openapi.md
    - how-to/extending-openapi.md
    - how-to/separate-openapi-schemas.md
    - how-to/custom-docs-ui-assets.md
    - how-to/configure-swagger-ui.md
    - how-to/sql-databases-peewee.md

So, what we will do next is add the code to document how that *external API* should look like to receive the callback from *your API*.

That documentation will show up in the Swagger UI at `/docs` in your API, and it will let external developers know how to build the *external API*.

We just scratched the surface, but you already get the idea of how it all works.

Try changing the line with:

```Python
    return {"item_name": item.name, "item_id": item_id}
```

...from:

```Python
        ... "item_name": item.name ...
```

...to:

```Python
        ... "item_price": item.price ...
```

...and see how your editor will auto-complete the attributes and know their types:

You have been reading here some of the main concepts that you would probably need to keep in mind when deciding how to deploy your application:

* Security - HTTPS
* Running on startup
* Restarts
* Replication (the number of processes running)
* Memory
* Previous steps before starting

We just scratched the surface, but you already get the idea of how it all works.

Try changing the line with:

```Python
    return {"item_name": item.name, "item_id": item_id}
```

...from:

```Python
        ... "item_name": item.name ...
```

...to:

```Python
        ... "item_price": item.price ...
```

...and see how your editor will auto-complete the attributes and know their types:

#### Check the `openapi.json`

If you are curious about how the raw OpenAPI schema looks like, FastAPI automatically generates a JSON (schema) with the descriptions of all your API.

You can see it directly at: <a href="http://127.0.0.1:8000/openapi.json" class="external-link" target="_blank">http://127.0.0.1:8000/openapi.json</a>.

It will show a JSON starting with something like:

```JSON
{
    "openapi": "3.1.0",

#-----------------------------------------------------------------------------
.PHONY: show.env show.goenv

show.env: ; $(info $(H) environment variables...)
	$(Q) printenv

show.goenv: ; $(info $(H) go environment...)
	$(Q) $(GO) version
	$(Q) $(GO) env

# show makefile variables. Usage: make show.<variable-name>
show.%: ; $(info $* $(H) $($*))
	$(Q) true

But it's not possible to have a running container without **at least one running process**. If the main process stops, the container stops.

## Build a Docker Image for FastAPI

Okay, let's build something now! 🚀

I'll show you how to build a **Docker image** for FastAPI **from scratch**, based on the **official Python** image.

This is what you would want to do in **most cases**, for example:

* Using **Kubernetes** or similar tools

If you need to check on [CI](http://builds.gradle.org/) status as an external contributor, you can click "Log in as guest".

## Useful tips

### How Gradle Works

We have [a series of blog](https://blog.gradle.org/how-gradle-works-1) that explains how Gradle works.
This may help you better understand and contribute to Gradle.

### Debugging Gradle

In most cases you would (and should) have a "termination proxy" handling HTTPS for you on top, this will depend on how you deploy your application, your provider might do this for you, or you might need to set it up yourself.

!!! tip