These features are what Marshmallow was built to provide. It is a great library, and I have used it a lot before.

But it was created before there existed Python type hints. So, to define every <abbr title="the definition of how data should be formed">schema</abbr> you need to use specific utils and classes provided by Marshmallow.

/// check | "Inspired **FastAPI** to"

Use code to define "schemas" that provide data types and validation, automatically.

/// tip

You could use any other SQL or NoSQL database library you want (in some cases called <abbr title="Object Relational Mapper, a fancy term for a library where some classes represent SQL tables and instances represent rows in those tables">"ORMs"</abbr>), FastAPI doesn't force you to use anything. 😎

///

#### MINIO_ETCD_ENDPOINTS

This is comma separated list of etcd servers that you want to use as the MinIO federation back-end. This should
be same across the federated deployment, i.e. all the MinIO instances within a federated deployment should use same
etcd back-end.

#### MINIO_DOMAIN

This is the top level domain name used for the federated setup. This domain name should ideally resolve to a load-balancer

With it, you can use <a href="https://docs.pytest.org/" class="external-link" target="_blank">pytest</a> directly with **FastAPI**.

## Using `TestClient`

/// info

To use `TestClient`, first install <a href="https://www.python-httpx.org" class="external-link" target="_blank">`httpx`</a>.

<font color="#3465A4">INFO    </font> Resolved absolute path <font color="#75507B">/home/user/code/awesomeapp/</font><font color="#AD7FA8">main.py</font>
<font color="#3465A4">INFO    </font> Searching for package file structure from directories with <font color="#3465A4">__init__.py</font> files
<font color="#3465A4">INFO    </font> Importing from <font color="#75507B">/home/user/code/</font><font color="#AD7FA8">awesomeapp</font>

# Conditional OpenAPI

If you needed to, you could use settings and environment variables to configure OpenAPI conditionally depending on the environment, and even disable it entirely.

## About security, APIs, and docs

Hiding your documentation user interfaces in production *shouldn't* be the way to protect your API.

That doesn't add any extra security to your API, the *path operations* will still be available where they are.

But that will only allow certain types of communication, excluding everything that involves credentials: Cookies, Authorization headers like those used with Bearer Tokens, etc.

So, for everything to work correctly, it's better to specify explicitly the allowed origins.

## Use `CORSMiddleware`

You can configure it in your **FastAPI** application using the `CORSMiddleware`.

* Import `CORSMiddleware`.

 * Fix problems with spdy/3.1 and http/2 where the wrong window size was being
   used.
 * Fix 1.5.0 regression where conditional cache responses could corrupt the
   connection pool.


## Version 1.5.0

_2014-03-07_


##### OkHttp no longer uses the default SSL context.

Applications that want to use the global SSL context with OkHttp should configure their
OkHttpClient instances with the following:

These invoices will have an `id`, `title` (optional), `customer`, and `total`.

The user of your API (an external developer) will create an invoice in your API with a POST request.

Then your API will (let's imagine):

* Send the invoice to some customer of the external developer.
* Collect the money.
* Send a notification back to the API user (the external developer).

**Spoiler alert**: the tutorial - user guide includes:

* Declaration of **parameters** from other different places as: **headers**, **cookies**, **form fields** and **files**.
* How to set **validation constraints** as `maximum_length` or `regex`.