Let's take this application as example:

{* ../../docs_src/query_params_str_validations/tutorial001_py310.py hl[7] *}

The query parameter `q` is of type `str | None`, that means that it's of type `str` but could also be `None`, and indeed, the default value is `None`, so FastAPI will know it's not required.

/// note

FastAPI will know that the value of `q` is not required because of the default value `= None`.

The above scenario is representative of most TLS set ups: the client uses certificates to validate
the identity of a server. The converse is also possible. Here we create a server that authenticates
a client and a client that authenticates a server.

```java
// Create the root for client and server to trust. We could also use different roots for each!
HeldCertificate rootCertificate = new HeldCertificate.Builder()
    .certificateAuthority(0)

        You can use [the template](https://github.com/gradle/gradle-issue-reproducer) with a Gradle GitHub action set up to showcase your problem.
        In the rare cases where this is infeasible, we will also accept a detailed set of instructions.
        You can also use [Gradle Project Replicator](https://github.com/android/project-replicator) to reproduce the structure of your project.
    validations:
      required: true
  - type: input

///

This is of course not the frontend for the final users, but it's a great automatic tool to document interactively all your API.

It can be used by the frontend team (that can also be yourself).

It can be used by third party applications and systems.

And it can also be used by yourself, to debug, check and test the same application.

## The `password` flow { #the-password-flow }

Now let's go back a bit and understand what is all that.

# Response Status Code { #response-status-code }

The same way you can specify a response model, you can also declare the HTTP status code used for the response with the parameter `status_code` in any of the *path operations*:

* `@app.get()`
* `@app.post()`
* `@app.put()`
* `@app.delete()`
* etc.

{* ../../docs_src/response_status_code/tutorial001_py39.py hl[6] *}

/// note

by setting `x-amz-storage-class=STANDARD/REDUCED_REDUNDANCY` for each object uploads so effectively utilizing the capacity of the cluster. Additionally these can also be enforced using IAM policies to make sure the client uploads with correct HTTP headers.

- MinIO also supports expansion of existing clusters in server pools. Each pool is a self contained entity with same SLA's (read/write quorum) for each object as original cluster. By using the existing namespace for lookup validation...

But for now, let's check these important **conceptual ideas**. These concepts also apply to any other type of web API. 💡

## Security - HTTPS { #security-https }

In the [previous chapter about HTTPS](https.md){.internal-link target=_blank} we learned about how HTTPS provides encryption for your API.

We also saw that HTTPS is normally provided by a component **external** to your application server, a **TLS Termination Proxy**.

It would also mean that if you get data from the `Request` object directly (for example, read the body) it won't be validated, converted or documented (with OpenAPI, for the automatic API user interface) by FastAPI.

`Manager.RegisterXHandler(handlerID, handler, subroutes...)`.

A `Handler()` function provides an HTTP handler, which should be hooked up to the appropriate route on the server.

On startup, the manager will start connecting to remotes and also starts listening for incoming connections.
Until a connection is established, all outgoing requests will return `ErrDisconnected`.

# Usage

## Single Payload Requests

   * <<<{{{./apidocs/org/apache/maven/api/cli/mvnup/package-summary.html}mvnup}}>>>, the Maven Upgrade tool.

 This API also defines {{{./core-extensions.html}Core Extensions model}} for <<<.mvn/extensions.xml>>>.