Tiny parser to get websocket messages from Google Chrome Developer Tools > Network > Export HAR...

chrome_websocket_messages.py

# !/usr/bin/env python3
# encoding: utf-8
import json

file_name = 'websocket.har'
f = open(file_name)
j = json.load(f)
entries = j['log']['entries']
for e in entries:
    if e['_resourceType'] == 'websocket' and '_webSocketMessages' in e.keys():
        messages = e['_webSocketMessages']
        for m in messages:
            if len(m['data']) > 1:
                print(m)