But it's the simplest way to focus on the server-side of WebSockets and have a working example:

{* ../../docs_src/websockets/tutorial001.py hl[2,6:38,41:43] *}

## Create a `websocket` { #create-a-websocket }

In your **FastAPI** application, create a `websocket`:

{* ../../docs_src/websockets/tutorial001.py hl[1,46:47] *}

/// note | Technical Details

You could also use `from starlette.websockets import WebSocket`.

func Stat(name string) (info os.FileInfo, err error) {
	defer updateOSMetrics(osMetricStat, name)(err)
	return os.Stat(name)
}

// Create captures time taken to call os.Create
func Create(name string) (f *os.File, err error) {
	defer updateOSMetrics(osMetricCreate, name)(err)
	return os.Create(name)
}

// Fdatasync captures time taken to call Fdatasync
func Fdatasync(f *os.File) (err error) {
	fn := ""
	if f != nil {

     * @return HTML response redirecting to the duplicate host list
     */
    @Execute
    @Secured({ ROLE })
    public HtmlResponse create(final CreateForm form) {
        verifyCrudMode(form.crudMode, CrudMode.CREATE);
        validate(form, messages -> {}, this::asEditHtml);
        verifyToken(this::asEditHtml);
        getDuplicateHost(form).ifPresent(entity -> {
            try {

      level = DeprecationLevel.ERROR,
    )
    fun body(): RequestBody = body

    companion object {
      @JvmStatic
      fun create(body: RequestBody): Part = create(null, body)

      @JvmStatic
      fun create(
        headers: Headers?,
        body: RequestBody,
      ): Part {
        require(headers?.get("Content-Type") == null) { "Unexpected header: Content-Type" }

        // Any PACDecodingException is acceptable for this test
        assertNotNull(e.getMessage());
    }

    @Test
    void testInvalidVersion() throws IOException {
        // Create minimal PAC structure with wrong version
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        writeLittleEndianInt(baos, 0); // buffer count = 0
        writeLittleEndianInt(baos, 99); // invalid version

     * @param encoding
     *            the encoding of the input stream (must not be {@literal null} or empty)
     * @return a {@link Reader} to read from the file
     */
    public static InputStreamReader create(final InputStream is, final String encoding) {
        assertArgumentNotNull("is", is);
        assertArgumentNotEmpty("encoding", encoding);

        try {
            return new InputStreamReader(is, encoding);

internal class StartStopExtension :
  BeforeEachCallback,
  BeforeAllCallback {
  override fun beforeAll(context: ExtensionContext) {
    val store = context.getStore(Namespace.create(StartStop::class.java))

    val staticFields =
      findAnnotatedFields(
        context.requiredTestClass,
        StartStop::class.java,
      ) { Modifier.isStatic(it.modifiers) }

	if !ok {
		t.Fatal("Unexpected object layer detected", reflect.TypeOf(obj))
	}

	// Tests for Erasure object layer initialization.

	// Create temporary backend for the test server.
	nDisks = 16
	disks, err = getRandomDisks(nDisks)
	if err != nil {
		t.Fatal("Failed to create drives for the backend")
	}
	defer removeRoots(disks)

	obj, err = newObjectLayer(ctx, mustGetPoolEndpoints(0, disks...))
	if err != nil {

     * Creates a new role setting.
     *
     * @param body the role data to create
     * @return JSON response containing the created role setting ID
     */
    // POST /api/admin/role/setting
    @Execute
    public JsonResponse<ApiResult> post$setting(final CreateBody body) {
        validateApi(body, messages -> {});
        body.crudMode = CrudMode.CREATE;
        final Role entity = getRole(body).orElseGet(() -> {

        assertThrows(NdrException.class, () -> m.decode(buf));
    }

    @Test
    void testRoundTripEncodeDecodeForResponseType() throws Exception {
        // Create a properly formatted response message
        NdrBuffer buf = new NdrBuffer(new byte[1024], 0);

        // Manually encode a response header
        buf.enc_ndr_small(5); // RPC version