lpsignal (Python)

Official Python SDK for LPSignal: net-of-IL APR signals for concentrated-liquidity pools. Python ≥ 3.10, built on httpx and websockets.

中文说明 · Node.js SDK: LPSignals/lpsignal-node · API docs

pip install lpsignal

REST

from lpsignal import LPSignal, LPSignalError

with LPSignal(api_key="lps_...") as lps:          # key optional for public endpoints
    page = lps.pools(chain="base", window=168, min_tvl_usd=1e6)
    top = page["pools"][0]
    detail = lps.pool("base", top["address"])     # every (window × range) metric
    bt = lps.backtest("base", top["address"], range_pct=5, days=7)
    try:
        lps.wallet_positions("0x...")
    except LPSignalError as e:
        if e.code == "pro_required":
            ...

AsyncLPSignal has the same methods as coroutines. Responses are the API's JSON (camelCase keys); lpsignal.types has TypedDicts for the main shapes.

Errors are LPSignalError with status, code (the API's error field), body and request_id. A 429 on a GET, PUT or DELETE is retried after its Retry-After (max_retries, default 2).

Stream

import asyncio
from lpsignal import AsyncLPSignal, FileLastIdStore, SignalStream

async def on_signal(signal, source):   # source: "rest" | "replay" | "live"
    ...                                # once per signal, in id order, never concurrently

async def main():
    lps = AsyncLPSignal(api_key="lps_...")   # Basic or Pro
    stream = SignalStream(lps, on_signal, store=FileLastIdStore("lpsignal-state.json"),
                          on_event=lambda e: print(e) if e["type"] == "fatal" else None)
    await stream.run()                        # or: await stream.start() … await stream.stop()

asyncio.run(main())

• First start with an empty store: begins after the newest signal that exists now (or after since).
• Every (re)connect: first fetches everything after the saved id over REST, repeating until a pass finds nothing new, then connects with ?since=<id>; anything at or below the saved id is dropped. No gap however long you were away, and no duplicates while the process runs.
• Your handler decides progress: the id is saved only after on_signal returns. If it raises, the connection is dropped and the signal is offered again. A crash after the handler but before the save also offers it again after the restart: delivery is at-least-once, so make the handler idempotent on signal["id"].
• No repeats even across crashes: keep the last id in the same database transaction as your side effects (write it inside on_signal), and pass a store that reads and writes that same row; its save() must only move forward (e.g. UPDATE … SET last_id = GREATEST(last_id, %s)), since the stream also saves the starting point.
• stop() waits for the signal being handled; nothing new is handed over after it is called. Cancelling run() stops the stream. Don't await stop() from inside on_signal (it would wait for itself). After a fatal event, call stop() before start() again.
• Fatal (the stream stops): invalid key (401), a plan without the stream (402), or the plan expiring (4402). Everything else reconnects with backoff.

The state file has the same format as the Node SDK's, so you can switch languages without losing your place.

Webhooks

from fastapi import FastAPI, Request, Response
from lpsignal import WebhookVerificationError, verify_webhook

app = FastAPI()

@app.post("/lpsignal")
async def lpsignal(request: Request):
    try:
        event = verify_webhook(await request.body(), request.headers, SECRET)
    except WebhookVerificationError as e:
        return Response(e.reason, status_code=400)
    # deliveries are at-least-once: skip event["deliveryId"] if already handled
    return Response(status_code=200)

Pass the raw body bytes, never re-serialised JSON. Deliveries older than 5 minutes are rejected (tolerance_sec); every retry is signed afresh.

License

MIT