WebSocket client for python

Posted 2021-01-01 fangbei

Project description

websocket-client module is WebSocket client for python. This provide the low level APIs for WebSocket. All APIs are the synchronous functions.

websocket-client supports only hybi-13.

License

• LGPL

Installation

This module is tested on Python 2.7 and Python 3.4+.

Type “python setup.py install” or “pip install websocket-client” to install.

Caution!

from v0.16.0, we can install by “pip install websocket-client” for Python 3.

This module depends on

• six
• backports.ssl_match_hostname for Python 2.x

performance

“send” method is too slow on pure python. If you want to get better performace, please install numpy or wsaccel. You can get the best performance from numpy.

How about Python 3

Now, we support Python 3 on single source code from version 0.14.0. Thanks, @battlemidget and @ralphbean.

HTTP Proxy

Support websocket access via http proxy. The proxy server must allow “CONNECT” method to websocket port. Default squid setting is “ALLOWED TO CONNECT ONLY HTTPS PORT”.

Current implementation of websocket-client is using “CONNECT” method via proxy.

example

import websocket
ws = websocket.WebSocket()
ws.connect("ws://example.com/websocket", http_proxy_host="proxy_host_name", http_proxy_port=3128)

Examples

Long-lived connection

This example is similar to how WebSocket code looks in browsers using JavaScript.

import websocket
try:
    import thread
except ImportError:
    import _thread as thread
import time

def on_message(ws, message):
    print(message)

def on_error(ws, error):
    print(error)

def on_close(ws):
    print("### closed ###")

def on_open(ws):
    def run(*args):
        for i in range(3):
            time.sleep(1)
            ws.send("Hello %d" % i)
        time.sleep(1)
        ws.close()
        print("thread terminating...")
    thread.start_new_thread(run, ())


if __name__ == "__main__":
    websocket.enableTrace(True)
    ws = websocket.WebSocketApp("ws://echo.websocket.org/",
                              on_message = on_message,
                              on_error = on_error,
                              on_close = on_close)
    ws.on_open = on_open
    ws.run_forever()

Short-lived one-off send-receive

This is if you want to communicate a short message and disconnect immediately when done.

from websocket import create_connection
ws = create_connection("ws://echo.websocket.org/")
print("Sending ‘Hello, World‘...")
ws.send("Hello, World")
print("Sent")
print("Receiving...")
result =  ws.recv()
print("Received ‘%s‘" % result)
ws.close()

If you want to customize socket options, set sockopt.

sockopt example

from websocket import create_connection
ws = create_connection("ws://echo.websocket.org/",
                        sockopt=((socket.IPPROTO_TCP, socket.TCP_NODELAY),))

More advanced: Custom class

You can also write your own class for the connection, if you want to handle the nitty-gritty details yourself.

import socket
from websocket import create_connection, WebSocket
class MyWebSocket(WebSocket):
    def recv_frame(self):
        frame = super().recv_frame()
        print(‘yay! I got this frame: ‘, frame)
        return frame

ws = create_connection("ws://echo.websocket.org/",
                        sockopt=((socket.IPPROTO_TCP, socket.TCP_NODELAY, 1),), class_=MyWebSocket)

 

FAQ

How to disable ssl cert verification?

Please set sslopt to {“cert_reqs”: ssl.CERT_NONE}.

WebSocketApp sample

ws = websocket.WebSocketApp("wss://echo.websocket.org")
ws.run_forever(sslopt={"cert_reqs": ssl.CERT_NONE})

create_connection sample

ws = websocket.create_connection("wss://echo.websocket.org",
  sslopt={"cert_reqs": ssl.CERT_NONE})

WebSocket sample

ws = websocket.WebSocket(sslopt={"cert_reqs": ssl.CERT_NONE})
ws.connect("wss://echo.websocket.org")

How to disable hostname verification.

Please set sslopt to {“check_hostname”: False}. (since v0.18.0)

WebSocketApp sample

ws = websocket.WebSocketApp("wss://echo.websocket.org")
ws.run_forever(sslopt={"check_hostname": False})

 

create_connection sample

ws = websocket.create_connection("wss://echo.websocket.org",
  sslopt={"check_hostname": False})

 

WebSocket sample

ws = websocket.WebSocket(sslopt={"check_hostname": False})
ws.connect("wss://echo.websocket.org")

How to enable SNI?

SNI support is available for Python 2.7.9+ and 3.2+. It will be enabled automatically whenever possible.

Sub Protocols.

The server needs to support sub protocols, please set the subprotocol like this.

Subprotocol sample

ws = websocket.create_connection("ws://example.com/websocket", subprotocols=["binary", "base64"])

wsdump.py

wsdump.py is simple WebSocket test(debug) tool.

sample for echo.websocket.org:

$ wsdump.py ws://echo.websocket.org/
Press Ctrl+C to quit
> Hello, WebSocket
< Hello, WebSocket
> How are you?
< How are you?

Usage

usage:

wsdump.py [-h] [-v [VERBOSE]] ws_url

WebSocket Simple Dump Tool

positional arguments:

ws_url websocket url. ex. ws://echo.websocket.org/

optional arguments:

-h, --help

show this help message and exit

WebSocketApp

-v VERBOSE, --verbose VERBOSE
	set verbose mode. If set to 1, show opcode. If set to 2, enable to trace websocket module

example:

$ wsdump.py ws://echo.websocket.org/
$ wsdump.py ws://echo.websocket.org/ -v
$ wsdump.py ws://echo.websocket.org/ -vv