# Custom Response Classes - File, HTML, Redirect, Streaming, etc.

There are several custom response classes you can use to create an instance and return them directly from your *path operations*.

Read more about it in the [FastAPI docs for Custom Response - HTML, Stream, File, others](https://fastapi.tiangolo.com/advanced/custom-response/).

You can import them directly from `fastapi.responses`:

```python
from fastapi.responses import (
    FileResponse,

    app = FastAPI()

    with pytest.raises(PydanticV1NotSupportedError):

        @app.post("/param")
        def endpoint(data: ParamModelV1):  # pragma: no cover
            return data


def test_raises_pydantic_v1_model_in_return_type() -> None:
    class ReturnModelV1(BaseModel):
        name: str

    app = FastAPI()

    with pytest.raises(PydanticV1NotSupportedError):

        @app.get("/return")

    shadowPackage: String
) {

    private
    val classes: MutableMap<String, ClassDetails> = linkedMapOf()

    val entryPoints: MutableSet<ClassDetails> = linkedSetOf()

    val shadowPackagePrefix =
        shadowPackage.takeIf(String::isNotEmpty)
            ?.let { it.replace('.', '/') + "/" }
            ?: ""

    operator fun get(className: String) =
        classes.computeIfAbsent(className) {

  </properties>

  <build>
    <directory>${project.basedir}/target</directory>
    <outputDirectory>${project.build.directory}/classes</outputDirectory>
    <finalName>${project.artifactId}-${project.version}</finalName>
    <testOutputDirectory>${project.build.directory}/test-classes</testOutputDirectory>
    <sourceDirectory>${project.basedir}/src/main/java</sourceDirectory>

        List<Exception> causes = null;
        List<AutoCloseable> cs = new ArrayList<>(closeables);
        Collections.reverse(cs);
        for (AutoCloseable c : cs) {
            if (c != null) {
                try {
                    c.close();
                } catch (Exception e) {
                    if (causes == null) {
                        causes = new ArrayList<>();
                    }

import org.jspecify.annotations.NullUnmarked;

/** Basic sanity tests for classes in {@code common.base}. */

@GwtIncompatible
@NullUnmarked
public class PackageSanityTests extends AbstractPackageSanityTests {
  public PackageSanityTests() {
    // package private classes like FunctionalEquivalence are tested through the public API.
    publicApiOnly();
  }

            <phase>process-classes</phase>
            <goals>
              <goal>manifest</goal>
            </goals>
          </execution>
        </executions>
        <configuration>
          <instructions>
            <!-- Silence a warning that claims that META-INF/versions/9/... is the "wrong directory" for our classes. -->
            <_fixupmessages>^Classes found in the wrong directory: .*</_fixupmessages>

You can import it directly form `fastapi`:

```python
from fastapi import WebSocketDisconnect
```

::: fastapi.WebSocketDisconnect

## WebSockets - additional classes

Additional classes for handling WebSockets.

Provided directly by Starlette, but you can import it from `fastapi`:

```python
from fastapi.websockets import WebSocketDisconnect, WebSocketState
```

~~ under the License.

 -----
 Introduction
 -----
 Hervé Boutemy
 -----
 2016-05-29
 -----

Maven Compat

 Maven2 classes maintained as compatibility layer for plugins that need to keep Maven2 compatibility.

 Plugins should avoid these classes and be updated to use only Maven3 dependencies (and require Maven3): see

        assertEquals(str, result);
    }

    /**
     * Test that default filter allows org.codelibs classes
     *
     * @throws Exception
     */
    public void testFromBinaryToObject_DefaultFilter_AllowsCodelibsClasses() throws Exception {
        // The default filter should allow org.codelibs.* classes
        final TestSerializableClass obj = new TestSerializableClass("test", 456);