hyperliquid-websocket

# Hyperliquid WebSocket Read-only, no key. Endpoints: `wss://api.hyperliquid.xyz/ws` (mainnet), `wss://api.hyperliquid-testnet.xyz/ws` (testnet). Prefer WebSocket over polling for anything continuous: fills, order updates, book and price watches. ## Protocol Subscribe: `{"method": "subscribe", "subscription": {...}}`. Unsubscribe with `"method": "unsubscribe"`. The server acknowledges with `{"channel": "subscriptionResponse", ...}` then streams `{"channel": "<type>", "data": ...}`. Send `{"method": "ping"}` periodically (the SDKs do it for you; the server expects activity within about a minute) and expect `{"channel": "pong"}`. Subscription types the desk uses: | Type | Subscription JSON | Data | | --- | --- | --- | | Mids for all markets | `{"type":"allMids"}` (optional `"dex"`) | `{"mids": {"BTC": "97123.5", ...}}` | | Order book | `{"type":"l2Book","coin":"ETH"}` (optional `nSigFigs`, `mantissa`, `fast: true` for 5 levels) | `{"coin","time","levels":[bids,asks]}`, up to 20 levels a side, pushed on each block at least 0.5 s after the last push | | Trades | `{"type":"trades","coin":"ETH"}` | array of `{coin, side, px, sz, time, hash, tid, users}` | | Candles | `{"type":"candle","coin":"ETH","interval":"1m"}` | `{t,T,s,i,o,c,h,l,v,n}` updated in place until the bar closes | | Best bid/offer | `{"type":"bbo","coin":"ETH"}` | `{"coin","time","bbo":[bid, ask]}` | | Asset context | `{"type":"activeAssetCtx","coin":"ETH"}` | funding, OI, mark, oracle, premium, volume for one ...