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

///

**Strategy**: `CrawlerClient`, `Extractor`, `Transformer` - pluggable implementations
**Builder**: `RequestDataBuilder`, `ExtractorBuilder` - fluent construction
**Template Method**: `AbstractCrawlerClient`, `AbstractExtractor` - common logic with overrides
**DI**: LastaFlute container with `@Resource` and XML config

### Core Principles

**Thread Safety**:
- `AtomicLong` for counters (`CrawlerContext.accessCount`)
- `volatile` for status flags

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.common.collect;

import com.google.caliper.Benchmark;
import com.google.caliper.Param;
import java.util.ArrayList;
import java.util.List;
import org.jspecify.annotations.NullUnmarked;

/**

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.common.primitives;

import com.google.caliper.BeforeExperiment;
import com.google.caliper.Benchmark;
import com.google.caliper.Param;
import java.util.Arrays;
import java.util.Comparator;
import java.util.Random;

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package common

enum class Arch(
    val suffix: String,
    val nameOnLinuxWindows: String,
    val nameOnMac: String,
) {
    AMD64("64bit", "amd64", "x86_64"),
    AARCH64("aarch64", "aarch64", "aarch64"),
    ;

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.common.io;

import static org.junit.Assert.assertThrows;

import java.io.Closeable;
import java.io.Flushable;
import java.io.IOException;
import java.io.Writer;
import org.jspecify.annotations.NullUnmarked;

/**

import org.codehaus.plexus.component.configurator.expression.ExpressionEvaluator;
import org.codehaus.plexus.configuration.PlexusConfiguration;

import static java.util.Objects.requireNonNull;

/**
 * Common implementations for plugin parameters configuration validation.
 *
 */
abstract class AbstractMavenPluginParametersValidator implements MavenPluginConfigurationValidator {

`Field` works the same way as `Query`, `Path` and `Body`, it has all the same parameters, etc.

/// note | Technical Details

Actually, `Query`, `Path` and others you'll see next create objects of subclasses of a common `Param` class, which is itself a subclass of Pydantic's `FieldInfo` class.

And Pydantic's `Field` returns an instance of `FieldInfo` as well.

	newAPIEndpoints = stripStandardPorts(apiEndpoints, "")
	if !reflect.DeepEqual(apiEndpoints, newAPIEndpoints) {
		t.Fatalf("Expected %#v, got %#v", apiEndpoints, newAPIEndpoints)
	}
}

// Test printing server common message.
func TestPrintServerCommonMessage(t *testing.T) {
	ctx, cancel := context.WithCancel(t.Context())
	defer cancel()

	obj, fsDir, err := prepareFS(ctx)
	if err != nil {
		t.Fatal(err)
	}

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package promotion

import common.VersionedSettingsBranch
import jetbrains.buildServer.configs.kotlin.triggers.ScheduleTrigger
import jetbrains.buildServer.configs.kotlin.triggers.ScheduleTrigger.SchedulingPolicy