# WebSockets

When defining WebSockets, you normally declare a parameter of type `WebSocket` and with it you can read data from the client and send data to it.

It is provided directly by Starlette, but you can import it from `fastapi`:

```python
from fastapi import WebSocket
```

/// tip

[kubernetes-client-linux-386.tar.gz](https://storage.googleapis.com/kubernetes-release/release/v1.2.7/kubernetes-client-linux-386.tar.gz) | `619e0a450cddf10ed1d42ed1d6330d41a75b9c1e00eb654cbe4b0422cd6099c5`

import org.codelibs.core.lang.StringUtil;
import org.codelibs.fess.Constants;
import org.codelibs.fess.crawler.client.CrawlerClientFactory;
import org.codelibs.fess.crawler.client.ftp.FtpClient;
import org.codelibs.fess.crawler.client.http.HcHttpClient;
import org.codelibs.fess.crawler.client.smb.SmbClient;
import org.codelibs.fess.mylasta.direction.FessConfig;
import org.codelibs.fess.util.ComponentUtil;

---------

This program downloads a URL and prints its contents as a string. [Full source][get_example].

```java
OkHttpClient client = new OkHttpClient();

String run(String url) throws IOException {
  Request request = new Request.Builder()
      .url(url)
      .build();

  try (Response response = client.newCall(request).execute()) {
    return response.body().string();
  }
}
```


Post to a Server

import java.util.Arrays;

import jcifs.CIFSContext;

/**
 * This class stores and encrypts NTLM user credentials. The default
 * credentials are retrieved from the {@code jcifs.smb.client.domain},
 * {@code jcifs.smb.client.username}, and {@code jcifs.smb.client.password}
 * properties.
 * <p>
 * Read <a href="../../../authhandler.html">jCIFS Exceptions and
 * NtlmAuthenticator</a> for related information.
 *

import okhttp3.Protocol
import okhttp3.Request

object ExternalHttp2Example {
  @JvmStatic
  fun main(args: Array<String>) {
    val client =
      OkHttpClient
        .Builder()
        .protocols(listOf(Protocol.HTTP_2, Protocol.HTTP_1_1))
        .build()
    val call =
      client.newCall(
        Request
          .Builder()
          .url("https://www.google.ca/")
          .build(),
      )

        byte[] server = hex("0102030405060708");
        byte[] client = hex("FEEDFACECAFEBEEF");

        // Act
        byte[] expected = NtlmUtil.computeResponse(key, server, client, 0, client.length);
        byte[] actual = NtlmUtil.getLMv2Response(key, server, client);

        // Assert
        assertArrayEquals(expected, actual);
    }

    @Test

```properties
# Lease configuration
jcifs.smb.client.useLeases=true
jcifs.smb.client.leaseTimeout=30000

# Persistent handles
jcifs.smb.client.usePersistentHandles=true
jcifs.smb.client.durableTimeout=120000

# Multi-channel
jcifs.smb.client.useMultiChannel=true
jcifs.smb.client.maxChannels=4
jcifs.smb.client.channelBindingPolicy=required

# Directory leasing
jcifs.smb.client.useDirectoryLeasing=true

type IAMEtcdStore struct {
	sync.RWMutex

	*iamCache

	usersSysType UsersSysType

	client *etcd.Client
}

func newIAMEtcdStore(client *etcd.Client, usersSysType UsersSysType) *IAMEtcdStore {
	return &IAMEtcdStore{
		iamCache:     newIamCache(),
		client:       client,
		usersSysType: usersSysType,
	}
}

func (ies *IAMEtcdStore) rlock() *iamCache {
	ies.RLock()
	return ies.iamCache

		Code:           "ExpiredToken",
		Description:    "The client grants that was passed is expired or is not valid. Get a new client grants token from the identity provider and then retry the request.",
		HTTPStatusCode: http.StatusBadRequest,
	},
	ErrSTSInvalidClientGrantsToken: {
		Code:           "InvalidClientGrantsToken",
		Description:    "The client grants token that was passed could not be validated by MinIO.",