For example, let's add <a href="https://github.com/Rebilly/ReDoc/blob/master/docs/redoc-vendor-extensions.md#x-logo" class="external-link" target="_blank">ReDoc's OpenAPI extension to include a custom logo</a>.

### Normal **FastAPI** { #normal-fastapi }

First, write all your **FastAPI** application as normally:

{* ../../docs_src/extending_openapi/tutorial001.py hl[1,4,7:9] *}

        testJvmVersion.toCapitalized() +
        "${vendor.displayName}${os.asName()}${arch.asName()}"

// Generates a Build Scan custom value "PartOf=X,Y,Z"
// where X, Y, Z are all the stages including current stage
// For example, for the stage PullRequestFeedback, the custom value will be "PartOf=PullRequestFeedback,ReadyForNightly,ReadyForRelease"
private fun Stage.getBuildScanCustomValues(): List<String> =
    StageName

        "czech_analyzer": {
          "type": "custom",
          "tokenizer": "standard",
          "filter": [
            "truncate20_filter",
            "lowercase",
            "czech_stop",
            "czech_keywords",
            "czech_override",
            "czech_stemmer"
          ]
        },
        "danish_analyzer": {
          "type": "custom",
          "tokenizer": "standard",

        "czech_analyzer": {
          "type": "custom",
          "tokenizer": "standard",
          "filter": [
            "truncate20_filter",
            "lowercase",
            "czech_stop",
            "czech_keywords",
            "czech_override",
            "czech_stemmer"
          ]
        },
        "danish_analyzer": {
          "type": "custom",
          "tokenizer": "standard",

# For most projects, this workflow file will not need changing; you simply need
# to commit it to your repository.
#
# You may wish to alter this file to override the set of languages analyzed,
# or to provide custom queries or build logic.
name: "CodeQL"

on:
  push:
    branches: [master]
  pull_request:
    # The branches below must be a subset of the branches above
    branches: [master]
  schedule:
    - cron: '0 11 * * 4'

jobs:

To add metadata to your OpenAPI schema, including a license, version, contact, etc, read the docs for [Tutorial - Metadata and Docs URLs](../tutorial/metadata.md){.internal-link target=_blank}.

## OpenAPI Custom URL { #openapi-custom-url }

To customize the OpenAPI URL (or remove it), read the docs for [Tutorial - Metadata and Docs URLs](../tutorial/metadata.md#openapi-url){.internal-link target=_blank}.

## OpenAPI Docs URLs { #openapi-docs-urls }

 * <p>
 * Qualifiers are used to distinguish between multiple beans of the same type,
 * allowing for more precise control over which implementation should be injected.
 * Custom qualifier annotations should be annotated with {@code @Qualifier}.
 * <p>
 * Example of creating a custom qualifier:
 * <pre>
 * {@literal @}Qualifier
 * {@literal @}Retention(RUNTIME)
 * public @interface Database {
 *     String value();
 * }
 * </pre>
 *

        // Create custom naming convention
        NamingConvention customNamingConvention = new MockNamingConvention() {
            @Override
            public String fromClassNameToComponentName(String className) {
                return super.fromClassNameToComponentName(className);
            }
        };

        // Create PagerCreator with custom naming convention

///

{* ../../docs_src/dependencies/tutorial008b_an_py39.py hl[18:22,31] *}

An alternative you could use to catch exceptions (and possibly also raise another `HTTPException`) is to create a [Custom Exception Handler](../handling-errors.md#install-custom-exception-handlers){.internal-link target=_blank}.

## Dependencies with `yield` and `except` { #dependencies-with-yield-and-except }

 * Each implementation must be registered in a {@code META-INF/services/} file corresponding
 * to the specific provider interface being implemented.
 * <p>
 * Example implementation for a custom language provider:
 * <pre>
 * public class CustomLanguageProvider implements LanguageProvider {
 *     public Collection&lt;Language&gt; provides() {
 *         return Arrays.asList(
 *             language("kotlin"),