# Advanced User Guide

## Additional Features

The main [Tutorial - User Guide](../tutorial/index.md){.internal-link target=_blank} should be enough to give you a tour through all the main features of **FastAPI**.

In the next sections you will see other options, configurations, and additional features.

!!! tip
    The next sections are **not necessarily "advanced"**.

    And it's possible that for your use case, the solution is in one of them.

       Best practice is to use the JIRA issue title in both the pull request title and in the first line of the commit message.
 - [ ] Write a pull request description that is detailed enough to understand what the pull request does, how, and why.
 - [ ] Run `mvn clean verify` to make sure basic checks pass. A more thorough check will
       be performed on your pull request automatically.

/**
 * Integration test to confirm that [TaskRunner] works with a real backend. Business logic is all
 * exercised by [TaskRunnerTest].
 *
 * This test is doing real sleeping with tolerances of 250 ms. Hopefully that's enough for even the
 * busiest of CI servers.
 */
@Tag("Slowish")
class TaskRunnerRealBackendTest {
  private val log = LinkedBlockingDeque<String>()

  private val loggingUncaughtExceptionHandler =

      }
      throw e
    }
  }

  private fun shouldIgnoreAndWaitForRealResponse(
    code: Int,
    exchange: Exchange,
  ): Boolean =
    when {
      // Server sent a 100-continue even though we did not request one. Try again to read the
      // actual response status.
      code == 100 -> true

      // Handle Processing (102) & Early Hints (103) and any new codes without failing

[here](https://github.com/tensorflow/tensorflow/commit/052445e04ce20fd747657e0198a1bcec2b6dff5b),
for an example.

See
[this commit](https://github.com/tensorflow/tensorflow/commit/5f7f05a80aac9b01325a78ec3fcff0dbedb1cc23)
as a rough example of the steps below.

All the files referenced below are located in the same directory as this README,
unless indicated otherwise.

1) Add the new version to the `VERSIONS` variable inside

  // different than the options the caller provided. e.g. for a patch request the performed
  // Operation might be a CREATE, in which case the Options will a
  // `meta.k8s.io/v1.CreateOptions` even though the caller provided `meta.k8s.io/v1.PatchOptions`.
  // +optional
  optional k8s.io.apimachinery.pkg.runtime.RawExtension options = 12;
}

// AdmissionResponse describes an admission response.

Helm charts `values.yaml` represent a complex user facing API that tends to grow uncontrollably over time
due to design choices in Helm.
The underlying Kubernetes resources we configure have 1000s of fields; given enough users and bespoke use cases,
eventually someone will want to customize every one of those fields.

    if (deferredPlans.isNotEmpty()) return deferredPlans.removeFirst() as FakePlan

    if (nextPlanIndex >= plans.size && autoGeneratePlans) addPlan()

    require(nextPlanIndex < plans.size) {
      "not enough plans! call addPlan() or set autoGeneratePlans=true in the test to set this up"
    }
    val result = plans[nextPlanIndex++]
    events += "take plan ${result.id}"

    if (result.yieldBeforePlanReturns) {

    ```

### Return values

And they can return values or not, the values won't be used.

So, you can re-use a normal dependency (that returns a value) you already use somewhere else, and even though the value won't be used, the dependency will be executed:

=== "Python 3.9+"

    ```Python hl_lines="11  16"
    {!> ../../../docs_src/dependencies/tutorial006_an_py39.py!}
    ```

=== "Python 3.8+"

            setOf("barchart-udt-bundle", "guava", "commons-cli")
        )

        // TODO: Gradle profiler should use the bundled tooling API.
        //   This should actually be handled by conflict resolution, though it doesn't seem to work.
        //   See https://github.com/gradle/gradle/issues/12002.
        withLibraryDependencies<DependencyRemovalByNameRule>(
            "org.gradle.profiler:gradle-profiler",