*
       * TODO(b/112550045): Allocating a single, cheaper listener is (I think) only an optimization.
       * If we make some other optimizations, this one will no longer be necessary. The optimization
       * could actually hurt in some cases, as it forces us to keep all inputs in memory until the
       * final input completes.
       */
      @RetainedLocalRef

    should not use them for communication between trusted and untrusted code.

6.  For the mainline flavor, we test the libraries using OpenJDK 8, 11, and 17
    on Linux, with some additional testing on newer JDKs and on Windows. Some
    features, especially in `com.google.common.io`, may not work correctly in
    non-Linux environments. For the Android flavor, our unit tests also run on
    API level 21 (Lollipop).

    for (StandardSystemProperty property : StandardSystemProperty.values()) {
      // Even though the contract in System.getProperties() specifies that a value will exist for
      // all of the listed keys, for some reason the "java.compiler" key returns null in some JVMs.
      if (property == JAVA_COMPILER) {
        continue;
      }
      // Removed in Java 9:

But it's still part of the same **FastAPI** application/web API (it's part of the same "Python Package").

You can create the *path operations* for that module using `APIRouter`.

### Import `APIRouter`

You import it and create an "instance" the same way you would with the class `FastAPI`:

```Python hl_lines="1  3" title="app/routers/users.py"

You can combine normal FastAPI *path operations* with GraphQL on the same application.

/// tip

**GraphQL** solves some very specific use cases.

It has **advantages** and **disadvantages** when compared to common **web APIs**.

Make sure you evaluate if the **benefits** for your use case compensate the **drawbacks**. 🤓

///

## GraphQL Libraries

			client: fakeClient(workingPod, workingPodDiedPreviously),
			config: config.RepairConfig{
				InitContainerName:  constants.ValidationContainerName,
				InitExitCode:       126,
				InitTerminationMsg: "Died for some reason",
				LabelKey:           "testkey",
				LabelValue:         "testval",
			},
			wantLabels: map[string]string{workingPod.Name: "", workingPodDiedPreviously.Name: ""},
			wantCount:  0,
		},
		{

I will show you some of the main concepts you should probably keep in mind when deploying a **FastAPI** application (although most of it applies to any other type of web application).

* `str`
* `bool`

But you can also use more complex data types.

And you will still have the same features as seen up to now:

* Great editor support.
* Data conversion from incoming requests.
* Data conversion for response data.
* Data validation.
* Automatic annotation and documentation.

## Other data types

Here are some of the additional data types you can use:

* `UUID`:

			input: []byte(`id,time,num,num2,text
1,2010-01-01T,7867786,4565.908123
2,2017-01-02T03:04Z,-5, 0.765111,Some some
`),
			// Since we are doing offset, no headers are used.
			wantResult: `{"id":"1","time":"2010-01-01T","num":"7867786","num2":"4565.908123"}
{"id":"2","time":"2017-01-02T03:04Z","num":"-5","num2":" 0.765111","text":"Some some"}`,
			wantErr: false,
			requestXML: []byte(`<?xml version="1.0" encoding="UTF-8"?>

## Check the Docs

You can verify it in the docs UI at `/docs`:

<div class="screenshot">
<img src="/img/tutorial/request-form-models/image01.png">
</div>

## Forbid Extra Form Fields

In some special use cases (probably not very common), you might want to **restrict** the form fields to only those declared in the Pydantic model. And **forbid** any **extra** fields.

/// note