### In production { #in-production }

In your production system, you probably have a frontend created with a modern framework like React, Vue.js or Angular.

And to communicate using WebSockets with your backend you would probably use your frontend's utilities.

Or you might have a native mobile application that communicates with your WebSocket backend directly, in native code.

pydantic==2.8.0
```

///

## Run Your Program { #run-your-program }

After you activated the virtual environment, you can run your program, and it will use the Python inside of your virtual environment with the packages you installed there.

<div class="termy">

```console
$ python main.py

Hello World
```

</div>

## Configure Your Editor { #configure-your-editor }

if %ERRORLEVEL% equ 0 goto execute

echo. 1>&2
echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. 1>&2
echo. 1>&2
echo Please set the JAVA_HOME variable in your environment to match the 1>&2
echo location of your Java installation. 1>&2

goto fail

:findJavaFromJavaHome
set JAVA_HOME=%JAVA_HOME:"=%
set JAVA_EXE=%JAVA_HOME%/bin/java.exe

if exist "%JAVA_EXE%" goto execute

If you feel lost with all these **"regular expression"** ideas, don't worry. They are a hard topic for many people. You can still do a lot of stuff without needing regular expressions yet.

Now you know that whenever you need them you can use them in **FastAPI**.

## Default values { #default-values }

You can, of course, use default values other than `None`.

This way you can add correct type annotations to your functions even when you are returning a type different than the response model, to be used by the editor and tools like mypy. And still you can have FastAPI do the data validation, documentation, etc. using the `response_model`.

# OpenAPI Callbacks { #openapi-callbacks }

You could create an API with a *path operation* that could trigger a request to an *external API* created by someone else (probably the same developer that would be *using* your API).

You can configure the two documentation user interfaces included:

* **Swagger UI**: served at `/docs`.
    * You can set its URL with the parameter `docs_url`.
    * You can disable it by setting `docs_url=None`.
* **ReDoc**: served at `/redoc`.
    * You can set its URL with the parameter `redoc_url`.
    * You can disable it by setting `redoc_url=None`.

* `title`: the title of your API.
* `oauth2_redirect_url`: you can use `app.swagger_ui_oauth2_redirect_url` here to use the default.
* `swagger_js_url`: the URL where the HTML for your Swagger UI docs can get the **JavaScript** file. This is the custom CDN URL.

you need access credentials for a successful exploit).

If you have not received a reply to your email within 48 hours or you have not heard from the security team
for the past five days please contact the security team directly:

- Primary security coordinator: ******@****.***
- Secondary coordinator: ******@****.***
- If you receive no response: ******@****.***

### Disclosure Process

    # - - - - - - - - - -/

    # /- - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
    # o extendedDBFluteInitializerClass: (NotRequired - Default null)
    #  If you want to extend the embedded DBFlute initializer,
    #  specify the class name of your original initializer
    #  that extends the embedded one.
    #  *Basically for fixed DBFluteConfig settings
    #