Ethereum Websocket Data Sending Issue: Passing Data from Class to Def

While running the binance.py file, one of the errors you might encounter is related to data transfer between classes and functions in Python. In this article, we will discuss how to resolve the issue when sending data using the Binance API via WebSockets.

Problem:

Let’s assume you have a class named MyClass with methods that handle WebSocket connections and send/receive data. When you call these methods from other classes or functions, you might encounter an error related to passing variables between them. This can be caused by the way Python handles function arguments.

Solution:

To resolve this issue, you need to pass variables as keyword arguments when calling your MyClass methods. Here’s how you can modify the code:

import websocket
from binance.client import Client
class MyClass:
def __init__(self):
self.data_to_send = None
async def handle_connection(self, websocket):









pass the data to send here as a keyword argument
self.data_to_send = "Greetings from MyClass!"
async def handle_data_received(self, data):
print(f"Received: {data}")
async def main():
client = client()
asynchronously with websockets.connect("wss://api.binance.com:9443") as websocket:
my_class = MyClass() 
create an instance of MyClass
await my_class.handle_connection(websocket)
while true:
data = await websocket.recv()
my_class.handle_data_received(data) 
pass data to send here
if __name__ == "__main__":
main()

Reasoning:

In the modified code, we create an instance of MyClass in the main() function and call its methods directly. When you try to pass variables between classes or functions without using keywords, Python throws TypeError. By passing variables as keyword arguments (self.data_to_send = "Greetings from MyClass!"), we can send data between classes.

Best practices:

To avoid potential problems with variable passing, consider using function and class methods instead of instance attributes. For example:

async def my_method(self):
self.send_data("Greetings from my class!")
def main():
client = client()
async with websockets.connect("wss://api.binance.com:9443") as websocket:
await my_method(websocket) 
pass to websocket method

instead of this
my_class = MyClass() 
create an instance of MyClass

then call the handle_connection and handle_data_received methods directly

By following these steps, you should be able to resolve the issue of passing data from class to def when using WebSockets with the Binance API.

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