# Query Parameters and String Validations { #query-parameters-and-string-validations }

**FastAPI** allows you to declare additional information and validation for your parameters.

Let's take this application as example:

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

For example, there's an official <a href="https://hub.docker.com/_/python" class="external-link" target="_blank">Python Image</a>.

And there are many other images for different things like databases, for example for:

* <a href="https://hub.docker.com/_/postgres" class="external-link" target="_blank">PostgreSQL</a>

        // Test when only baseDn is set
        ComponentUtil.setFessConfig(new FessConfig.SimpleImpl() {
            @Override
            public String getLdapBaseDn() {
                return "dc=example,dc=com";
            }

            @Override
            public String getLdapAccountFilter() {
                return "";
            }
        });

        // Test registerSmbURLHandler when java.protocol.handler.pkgs does not contain "jcifs"
        System.setProperty("java.protocol.handler.pkgs", "com.example");
        SingletonContext.registerSmbURLHandler();
        assertEquals("com.example|jcifs", System.getProperty("java.protocol.handler.pkgs"));
    }

    @Test
    void testRegisterSmbURLHandlerWhenPkgsAlreadyContainsJcifs() {

The `TestClient` is based on <a href="https://www.python-httpx.org" class="external-link" target="_blank">HTTPX</a>, and luckily, we can use it directly to test the API.

## Example { #example }

For a simple example, let's consider a file structure similar to the one described in [Bigger Applications](../tutorial/bigger-applications.md){.internal-link target=_blank} and [Testing](../tutorial/testing.md){.internal-link target=_blank}:

import javax.security.auth.callback.UnsupportedCallbackException
import okhttp3.OkHttpClient
import okhttp3.Request
import okhttp3.internal.SuppressSignatureCheck
import okhttp3.internal.platform.Platform

/**
 * Example of using a hardware key to perform client auth.
 * Prefer recent JDK builds, and results are temperamental to slight environment changes.
 * Different instructions and configuration may be required for other hardware devices.
 *

objectClass: inetOrgPerson
cn: Alice Smith
sn: Smith
uid: alice1
mail: alice@example.io
userPassword: {SSHA}Yeh2/IV/q/HjG2yzN3YdE9CAF3EJFCLu

dn: uid=bobfisher,ou=people,ou=hwengg,dc=min,dc=io
objectClass: inetOrgPerson
cn: Robert Fisher
sn: Fisher
uid: bobfisher
mail: bob@example.io
userPassword: {SSHA}LktfbhK5oXSdDWCNzauJ9JA+Poxinl3y

dn: uid=cody3,ou=people,ou=hwengg,dc=min,dc=io

	Porque estamos usando uma URL relativa, se sua API estava localizada em `https://example.com/`, então irá referir-se à `https://example.com/token`. Mas se sua API estava localizada em `https://example.com/api/v1/`, então irá referir-se à `https://example.com/api/v1/token`.

    @Mock
    private CredentialsInternal credentialsInternal;
    @Mock
    private SmbTransportImpl transport;

    private SmbSessionImpl newSession() {
        return new SmbSessionImpl(cifsContext, "server.example", "EXAMPLE", transport);
    }

    @BeforeEach
    void setup() {
        // Base context configuration - always needed
        when(cifsContext.getConfig()).thenReturn(configuration);

This document focuses on showing a working example on how to use Object Lambda with MinIO, you must have [MinIO deployed in your environment](https://docs.min.io/community/minio-object-store/operations/installation.html) before you can start using external lambda functions. You also must install Python version 3.8 or later for the lambda handlers to work.

## Example Lambda handler

Install the necessary dependencies.
```sh