## 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`.

**FastAPI** provides the same `WebSocket` directly just as a convenience for you, the developer. But it comes directly from Starlette.

///

# Testing WebSockets { #testing-websockets }

You can use the same `TestClient` to test WebSockets.

For this, you use the `TestClient` in a `with` statement, connecting to the WebSocket:

{* ../../docs_src/app_testing/tutorial002.py hl[27:31] *}

/// note

For more details, check Starlette's documentation for <a href="https://www.starlette.io/testclient/#testing-websocket-sessions" class="external-link" target="_blank">testing WebSockets</a>.

}

public abstract class okhttp3/WebSocketListener {
	public fun <init> ()V
	public fun onClosed (Lokhttp3/WebSocket;ILjava/lang/String;)V
	public fun onClosing (Lokhttp3/WebSocket;ILjava/lang/String;)V
	public fun onFailure (Lokhttp3/WebSocket;Ljava/lang/Throwable;Lokhttp3/Response;)V
	public fun onMessage (Lokhttp3/WebSocket;Ljava/lang/String;)V

	github.com/googleapis/enterprise-certificate-proxy v0.3.6 // indirect
	github.com/googleapis/gax-go/v2 v2.14.1 // indirect
	github.com/gorilla/mux v1.8.1 // indirect
	github.com/gorilla/websocket v1.5.3 // indirect
	github.com/hashicorp/errwrap v1.1.0 // indirect
	github.com/hashicorp/go-multierror v1.1.1 // indirect
	github.com/hashicorp/go-uuid v1.0.3 // indirect
	github.com/hashicorp/golang-lru v1.0.2 // indirect

}

public abstract class okhttp3/WebSocketListener {
	public fun <init> ()V
	public fun onClosed (Lokhttp3/WebSocket;ILjava/lang/String;)V
	public fun onClosing (Lokhttp3/WebSocket;ILjava/lang/String;)V
	public fun onFailure (Lokhttp3/WebSocket;Ljava/lang/Throwable;Lokhttp3/Response;)V
	public fun onMessage (Lokhttp3/WebSocket;Ljava/lang/String;)V

// IsOnline - returns whether client failed to connect or not.
func (client *storageRESTClient) IsOnline() bool {
	return client.restClient.IsOnline() || client.IsOnlineWS()
}

// IsOnlineWS - returns whether websocket client failed to connect or not.
func (client *storageRESTClient) IsOnlineWS() bool {
	return client.gridConn.State() == grid.StateConnected
}

// LastConn - returns when the disk is seen to be connected the last time

* Seriously impressive performance. It is <a href="https://github.com/encode/starlette#performance" class="external-link" target="_blank">one of the fastest Python frameworks available, on par with **NodeJS** and **Go**</a>.
* **WebSocket** support.
* In-process background tasks.
* Startup and shutdown events.
* Test client built on HTTPX.
* **CORS**, GZip, Static Files, Streaming responses.
* **Session and Cookie** support.
* 100% test coverage.

github.com/gorilla/securecookie v1.1.1/go.mod h1:ra0sb63/xPlUeL+yeDciTfxMRAA+MP+HVt/4epWDjd4=
github.com/gorilla/sessions v1.2.1/go.mod h1:dk2InVEVJ0sfLlnXv9EAgkf6ecYs/i80K/zI+bUmuGM=
github.com/gorilla/websocket v1.5.3 h1:saDtZ6Pbx/0u+bgYQ3q96pZgCzfhKXGPqt7kZ72aNNg=
github.com/gorilla/websocket v1.5.3/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
github.com/hashicorp/errwrap v1.0.0/go.mod h1:YH+1FKiLXxHSkmPseP+kNlulaMuP3n2brvKWEqk/Jc4=

* Integrasi **GraphQL** dengan <a href="https://strawberry.rocks" class="external-link" target="_blank">Strawberry</a> dan library lainnya.
* Fitur lainnya (berkat Starlette) seperti:
    * **WebSocket**
    * Test yang sangat mudah berdasarkan HTTPX dan `pytest`
    * **CORS**
    * **Cookie Session**
    * ...dan lainnya.

## Performa

It is very simple and intuitive. It's designed to be easily extensible, and have modular components.

It has:

* Seriously impressive performance.
* WebSocket support.
* In-process background tasks.
* Startup and shutdown events.
* Test client built on HTTPX.
* CORS, GZip, Static Files, Streaming responses.
* Session and Cookie support.
* 100% test coverage.