Delta Exchange Python SDK

A typed Python client for the Delta Exchange v2 REST API and real-time WebSocket feed. It is based on the API snapshot in docs/delta-exchange-api-docs.md.

This is a community SDK. Test trading code on the demo environment before using real funds.

Features

• Public and signed REST requests
• Helpers for market data, orders, positions, wallets, account settings, MMP, and deadman switch
• Generic request() method for newly released v2 endpoints
• Cursor pagination iterator
• Async WebSocket client with key-auth, heartbeat monitoring, reconnection, and subscription replay
• Built-in India/global REST and India WebSocket endpoint selection
• Structured exceptions and complete type hints

Install

pip install delta-rest-ws

Python 3.9 or newer is required.

REST quick start

Public endpoints need no credentials:

from delta_rest_ws import DeltaRestClient, Environment

client = DeltaRestClient(environment=Environment.INDIA_TESTNET)

products = client.get_products({"states": "live"})
ticker = client.get_ticker("BTCUSD")
candles = client.get_candles(
    symbol="BTCUSD",
    resolution="5m",
    start=1722511635,
    end=1722598035,
)
client.close()

Private endpoints are signed automatically:

from delta_rest_ws import DeltaRestClient, Environment, OrderType

with DeltaRestClient(
    environment=Environment.INDIA_TESTNET,
    api_key="YOUR_API_KEY",
    api_secret="YOUR_API_SECRET",
) as client:
    order = client.place_order(
        product_id=27,
        size=1,
        side="buy",
        order_type=OrderType.LIMIT,
        limit_price="50000",
        client_order_id="strategy-001",
    )
    client.cancel_order(product_id=27, order_id=order["id"])

Do not commit API credentials. Read them from environment variables or a secrets manager.

Environments

The bundled API documentation only declares India WebSocket URLs, so the SDK does not guess global socket endpoints.

Pagination

for page in client.iter_pages(
    "/fills",
    query={"contract_types": "perpetual_futures"},
):
    for fill in page:
        print(fill)

order_history() and fills() return the full API envelope so result and meta.after remain available. Most other helpers return the result value directly.

Calling a new endpoint

result = client.request(
    "GET",
    "/v2/some_future_endpoint",
    query={"symbol": "BTCUSD"},
    auth=True,
)

WebSocket quick start

Subscriptions may be registered before connecting. They are sent on connect and restored after any reconnect.

import asyncio

from delta_rest_ws import Channel, DeltaWebSocketClient, Environment


async def main():
    ws = DeltaWebSocketClient(
        environment=Environment.INDIA_TESTNET,
        public=True,
    )
    await ws.subscribe(Channel.TICKER, ["BTCUSD", "ETHUSD"])
    await ws.subscribe("candlestick_1m", ["MARK:BTCUSD"])

    try:
        async for message in ws.messages():
            print(message)
    finally:
        await ws.close()


asyncio.run(main())

Private streams authenticate before subscriptions are sent:

ws = DeltaWebSocketClient(
    environment=Environment.INDIA_TESTNET,
    api_key="YOUR_API_KEY",
    api_secret="YOUR_API_SECRET",
)
await ws.subscribe(Channel.ORDERS, ["all"])
await ws.subscribe(Channel.POSITIONS, ["all"])

async for message in ws.messages():
    print(message)

The client enables Delta's server heartbeat and uses a 40-second receive timeout by default. It also sends WebSocket ping frames every 30 seconds and expects a pong within 5 seconds.

Errors

from delta_rest_ws import DeltaAPIError, DeltaHTTPError

try:
    client.get_profile()
except DeltaHTTPError as error:
    print(error.status_code, error)
except DeltaAPIError as error:
    print(error.code, error.context, error)

Development

python -m pip install -e ".[dev]"
ruff check .
pytest
python -m build
python -m twine check dist/*

License

MIT License.