betfairlightweight

Enabling lightweight=True instructs the library to return raw JSON instead of creating complex Python objects. This is significantly faster because it avoids object instantiation overhead, though the data is harder to work with. You can enable it globally during client initialization or per request.

# Global initialization
>>> trading = betfairlightweight.APIClient(
        "username", 
        "password", 
        app_key="app_key", 
        certs="/certs", 
        lightweight=True,
    )
>>> trading.login()
{'sessionToken': 'dfgrtegreg===rgrgr', 'loginStatus': 'SUCCESS'}

# Per request
>>> trading.betting.list_event_types(
        filter=filters.market_filter(
            text_query='Horse Racing'
        ),
        lightweight=True,
    )
[{'eventType': {'id': '7', 'name': 'Horse Racing'}, 'marketCount': 328}]

To use betfairlightweight, import the library and instantiate APIClient. You can log in using SSL certificates (strongly recommended for security and 2FA) or via an interactive login method if certificates are not configured.

Once logged in, the client maintains the session_token and session_expired status. You can use keep_alive() to maintain the session or logout() to end it.

import betfairlightweight

# Using SSL certificates (Recommended)
trading = betfairlightweight.APIClient(
    "username", "password", app_key="app_key", certs="/certs"
)
trading.login()

# Using interactive login (If no certificates)
trading = betfairlightweight.APIClient(
    "username", "password", app_key="app_key"
)
trading.login_interactive()

# Session management
trading.keep_alive()
trading.logout()

If you lose connection, you can resubscribe to avoid receiving a full image (which saves bandwidth and time). To do this, pass the initial_clk and clk from your existing StreamListener into the subscribe_to_markets call.

streaming_unique_id = stream.subscribe_to_markets(
    market_filter=market_filter,
    market_data_filter=market_data_filter,
    conflate_ms=1000,
    initial_clk=listener.initial_clk,
    clk=listener.clk,
)

Betfair uses different endpoints depending on your country of residence. You can specify the locale during APIClient initialization to ensure you are using the correct endpoints for your region.

>>> trading = betfairlightweight.APIClient(
        "username", 
        "password", 
        app_key="app_key", 
        locale="italy"
    )

To interact with the Betfair API, instantiate an APIClient with your credentials and app key. If using SSL certificates, provide the path to the directory containing them via the certs parameter. Call .login() to establish a session.

Required parameters for APIClient:

• username: Your Betfair username.
• password: Your Betfair password.
• app_key: Your Betfair application key.
• certs: (Optional) Path to your SSL certificates directory.

import betfairlightweight

trading = betfairlightweight.APIClient(
    "username", "password", app_key="app_key", certs="/certs"
)
trading.login()

To improve the speed of backtesting, you can configure specific settings on the StreamListener to reduce overhead.

listener = betfairlightweight.StreamListener(
    max_latency=None,  # ignore latency errors
    output_queue=None,  # use generator rather than a queue (faster)
    lightweight=True,  # lightweight mode is faster
    update_clk=False,  # do not update clk on updates (not required when backtesting)
)

Install the base package using pip. Note that betfairlightweight requires Python 3.9 or higher.

For improved performance, install the [speed] extra to include ciso8601 (C-based datetime parsing) and orjson (Rust-based JSON parsing).

$ pip install betfairlightweight

# For high-performance installation with C/Rust libraries:
$ pip install betfairlightweight[speed]

Danish residents are subject to NemID requirements. To log in, you must manually replicate the login flow by posting to the login_interactive.url and extracting the ssoid from the Set-Cookie header to set the session token.

import re
import betfairlightweight

trading = betfairlightweight.APIClient("username", "password", app_key="app_key")

resp = trading.session.post(
    url=trading.login_interactive.url,
    data={
        "username": trading.username,
        "password": trading.password,
        "redirectMethod": "POST",
        "product": trading.app_key,
        "url": "https://www.betfair.com",
        "submitForm": True,
    }
)
session_token = re.findall(
    "ssoid=(.*?);", resp.headers["Set-Cookie"]
)
trading.set_session_token(session_token[0])

print(trading.betting.list_event_types())

Install the standard version of the library using pip:

$ pip install betfairlightweight

To enable high-performance mode using C and Rust libraries, install with the [speed] extra:

$ pip install betfairlightweight[speed]

On Linux and macOS, betfairlightweight installs C and Rust-based libraries automatically. Windows users should install the [speed] extra to get these performance improvements. Note that Visual Studio may be required on Windows for these installations.

$ pip install betfairlightweight[speed]