### Use cases: external service { #use-cases-external-service }

An example could be that you have an external authentication provider that you need to call.

You send it a token and it returns an authenticated user.

This provider might be charging you per request, and calling it might take some extra time than if you had a fixed mock user for tests.

* Add more granular permission controls with OAuth2 scopes where needed.
* ...etc.

Nevertheless, you might have a very specific use case where you really need to disable the API docs for some environment (e.g. for production) or depending on configurations from environment variables.

## Conditional OpenAPI from settings and env vars { #conditional-openapi-from-settings-and-env-vars }

For that, you can use the `WSGIMiddleware` and use it to wrap your WSGI application, for example, Flask, Django, etc.

## Using `WSGIMiddleware` { #using-wsgimiddleware }

You need to import `WSGIMiddleware`.

Then wrap the WSGI (e.g. Flask) app with the middleware.

And then mount that under a path.

{* ../../docs_src/wsgi/tutorial001_py39.py hl[2:3,3] *}

## Check it { #check-it }

  - type: markdown
    attributes:
      value: |
        Please search related information in our [latest documentation](https://docs.gradle.org/current/userguide/userguide.html) before opening a documentation issue.
        If you need help with Gradle or have a usage question, please reach [our community](http://help.gradle.org/) instead of creating an issue.

        If you found a clear typo, please open a PR with a fix instead of opening an issue.

I'll tell you a bit more about these **concepts** here, and that would hopefully give you the **intuition** you would need to decide how to deploy your API in very different environments, possibly even in **future** ones that don't exist yet.

By considering these concepts, you will be able to **evaluate and design** the best way to deploy **your own APIs**.

-----------------

The equivalent of static methods in Java is companion object functions in Kotlin. The bytecode is
the same but `.kt` files now need `Companion` in the import.

This works with OkHttp 3.x:

```kotlin
import okhttp3.CipherSuite.forJavaName
```

But OkHttp 4.x needs a `Companion`:

```kotlin
import okhttp3.CipherSuite.Companion.forJavaName
```

* The frontend stores that token temporarily somewhere.
* The user clicks in the frontend to go to another section of the frontend web app.
* The frontend needs to fetch some more data from the API.
    * But it needs authentication for that specific endpoint.
    * So, to authenticate with our API, it sends a header `Authorization` with a value of `Bearer ` plus the token.

       */

      //
      seenExceptionsLocal = newConcurrentHashSet();
      /*
       * Other handleException() callers may see this as soon as we publish it. We need to populate
       * it with the initial failure before we do, or else they may think that the initial failure
       * has never been seen before.
       */
      addInitialException(seenExceptionsLocal);

   * a duration in order to call a legacy API which requires a {@code long, TimeUnit} pair.
   */
  // We use this method only for cases in which we need to decompose to primitives.
  @SuppressWarnings({"GoodTime-ApiWithNumericTimeUnit", "GoodTime-DecomposeToPrimitive"})
  @IgnoreJRERequirement
  static long toNanosSaturated(Duration duration) {

    public abstract DirectoryProperty getReleaseNotesAssets();

    /**
     * The Jquery file to include in the release notes.
     */
    public abstract ConfigurableFileCollection getJquery();

    // TODO: Need staging root property too

    /**
     * The collection of rendered documentation.
     */
    public abstract RegularFileProperty getRenderedDocumentation();