Error handling

Every error BinomoAPI raises derives from BinomoAPIException, so a single except catches them all, and the subclasses let you react precisely.

  1. Exception hierarchy
  2. A robust template
  3. Retry with exponential backoff
  4. Re-login when the session expires
  5. Debug logging
  6. Common errors

Exception hierarchy

Exception Raised when What to do
BinomoAPIException Base class; also unexpected HTTP or JSON responses Log it; retry later
AuthenticationError Wrong email/password, login rejected (HTTP 401/422), token expired Check credentials; log in again
ConnectionError Network down, timeout, Binomo 5xx, WebSocket failed Back off and retry
InvalidParameterError Empty credentials, non-positive amount or duration, unknown asset Fix your input; don’t retry
TradeError The order couldn’t be sent Reconnect, then retry once
InsufficientBalanceError Subclass of TradeError, reserved for balance failures Stop trading

BinomoAPI’s ConnectionError is not Python’s built-in ConnectionError. Import it explicitly with from BinomoAPI import ConnectionError, or catch BinomoAPIException.

A robust template 

import asyncio
from BinomoAPI import (
    BinomoAPI, BinomoAPIException, AuthenticationError,
    ConnectionError, InvalidParameterError, TradeError,
)

async def run(email, password):
    try:
        login = BinomoAPI.login(email, password)
    except AuthenticationError as e:
        raise SystemExit(f"Login failed, check your credentials: {e}")

    async with BinomoAPI.create_from_login(login, demo=True) as api:
        try:
            await api.place_call_option("EURO", 60, 100)
        except InvalidParameterError as e:
            print("Bad input:", e)                 # bug in your code; don't retry
        except TradeError as e:
            print("Order not sent:", e)            # retry after reconnecting
        except ConnectionError as e:
            print("Network problem:", e)
        except BinomoAPIException as e:
            print("Unexpected API error:", e)

Retry with exponential backoff

Transient errors such as timeouts, 5xx responses or a dropped WebSocket usually clear up on their own. Retry those, but never retry InvalidParameterError or AuthenticationError in a loop:

import asyncio
from BinomoAPI import ConnectionError, TradeError

async def with_retry(make_call, attempts=3, base_delay=1.0):
    for attempt in range(1, attempts + 1):
        try:
            return await make_call()
        except (ConnectionError, TradeError):
            if attempt == attempts:
                raise
            await asyncio.sleep(base_delay * 2 ** (attempt - 1))

result = await with_retry(lambda: api.place_put_option("EURO", 60, 100))

Re-login when the session expires

Long-running bots eventually lose their session. Catch AuthenticationError, log in again and rebuild the client:

async def get_balance_with_relogin(api, email, password):
    try:
        return api, await api.get_balance()
    except AuthenticationError:
        await api.close()
        login = BinomoAPI.login(email, password)
        api = BinomoAPI.create_from_login(login, demo=True)
        return api, await api.get_balance()

Debug logging

Turn on logging to see every request, response and WebSocket message:

import logging
logging.basicConfig(level=logging.DEBUG)

api = BinomoAPI.create_from_login(login, enable_logging=True, log_level=logging.DEBUG)

Debug logs include your auth token and request headers. Don’t paste them publicly. Redact the token before you share logs in an issue or on Discord.

Common errors

Message Cause Fix
Invalid email or password Wrong credentials, or the account uses Google/Facebook sign-in Set a password on Binomo and use it
Login rejected by Binomo (422 ...) Binomo rejected the request, often after many attempts or a new captcha Log in once in the browser, wait a few minutes, retry
Unknown asset: ... You passed a name instead of a RIC Use the RIC from the Asset List
Session validation failed Token expired or a different device_id was used Log in again; keep the device_id consistent
WebSocket connection failed Network issue or Binomo maintenance Retry with backoff

Still stuck? Search the FAQ, open an issue, or ask in Discord.