</div>

## Forbid Extra Form Fields { #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

This is supported since FastAPI version `0.114.0`. 🤓

///

You can use Pydantic's model configuration to `forbid` any `extra` fields:

  // Start the server.
  server.start();

  // Ask the server for its URL. You'll need this to make HTTP requests.
  HttpUrl baseUrl = server.url("/v1/chat/");

  // Exercise your application code, which should make those HTTP requests.
  // Responses are returned in the same order that they are enqueued.
  Chat chat = new Chat(baseUrl);

  chat.loadMore();
  assertEquals("hello, world!", chat.messages());

  chat.loadMore();

 * This interface extends the general {@link Options} interface, adding Maven-specific configuration options.
 *
 * <p>These options represent the various flags and settings available through the Maven CLI,
 * as well as those that can be specified in the {@code maven.config} file. They provide fine-grained
 * control over Maven's behavior during the build process.</p>
 *
 * @since 4.0.0
 */
@Experimental

          excluding those notices that do not pertain to any part of
          the Derivative Works; and

      (d) If the Work includes a "NOTICE" text file as part of its
          distribution, then any Derivative Works that You distribute must
          include a readable copy of the attribution notices contained
          within such NOTICE file, excluding those notices that do not

          excluding those notices that do not pertain to any part of
          the Derivative Works; and

      (d) If the Work includes a "NOTICE" text file as part of its
          distribution, then any Derivative Works that You distribute must
          include a readable copy of the attribution notices contained
          within such NOTICE file, excluding those notices that do not

 *
 * <p><b>{@code default} method warning:</b> This class does <i>not</i> forward calls to {@code
 * default} methods. Instead, it inherits their default implementations. When those implementations
 * invoke methods, they invoke methods on the {@code ForwardingListeningExecutorService}.
 *
 * @author Isaac Shum
 * @since 10.0
 */
@J2ktIncompatible
@GwtIncompatible

import java.lang.annotation.Target;

/**
 * Signifies that a test should not be run under Android. This annotation is respected only by our
 * Google-internal Android suite generators. Note that those generators also suppress any test
 * annotated with LargeTest.
 *
 * <p>For more discussion, see {@linkplain com.google.common.base.AndroidIncompatible the
 * documentation on another copy of this annotation}.
 */

import java.lang.annotation.Target;

/**
 * Signifies that a test should not be run under Android. This annotation is respected only by our
 * Google-internal Android suite generators. Note that those generators also suppress any test
 * annotated with LargeTest.
 *
 * <p>For more discussion, see {@linkplain com.google.common.base.AndroidIncompatible the
 * documentation on another copy of this annotation}.
 */

import java.lang.annotation.Target;

/**
 * Signifies that a test should not be run under Android. This annotation is respected only by our
 * Google-internal Android suite generators. Note that those generators also suppress any test
 * annotated with LargeTest.
 *
 * <p>For more discussion, see {@linkplain com.google.common.base.AndroidIncompatible the
 * documentation on another copy of this annotation}.
 */

import java.lang.annotation.Target;

/**
 * Signifies that a test should not be run under Android. This annotation is respected only by our
 * Google-internal Android suite generators. Note that those generators also suppress any test
 * annotated with LargeTest.
 *
 * <p>For more discussion, see {@linkplain com.google.common.base.AndroidIncompatible the
 * documentation on another copy of this annotation}.
 */