DFlow Market Data (Streaming)

Real-time market data for Solana spot pairs over WebSocket. Read-only: this streams prices, depth, and fee estimates for display and analysis. To execute a swap, use dflow-spot-trading.

The three streams

All are paths on the DFlow Trade API WebSocket host (prod wss://quote-api.dflow.net, dev wss://dev-quote-api.dflow.net). One connection; subscribe per pair.

Keep the key on the backend (proxy the stream)

As a security best practice, keep your DFlow API key on the backend, not in browser code where anyone can read it. Stream through a backend proxy that holds the key, connects to DFlow, and relays messages to the browser.

A server-side app (Node/CLI, no browser) is already the trusted backend, so it connects directly with the key as an x-api-key header.

// Backend relay (Node, `ws`). The browser connects to THIS; the backend holds the key.
import { WebSocketServer, WebSocket } from "ws";
const wss = new WebSocketServer({ server });          // same origin as your app
wss.on("connection", (client) => {
  const up = new WebSocket(`${process.env.DFLOW_TRADE_API_WS_URL}/book-stream`,
    { headers: { "x-api-key": process.env.DFLOW_API_KEY } });
  const q = [];
  up.on("open", () => { q.forEach((m) => up.send(m)); q.length = 0; });
  up.on("message", (d) => client.readyState === 1 && client.send(d.toString()));
  client.on("message", (m) => up.readyState === 1 ? up.send(m.toString()) : q.push(m.toString()));
  client.on("close", () => up.close()); up.on("close", () => client.close());
});

Prerequisites

• DFlow docs MCP (https://pond.dflow.net/mcp): this skill is the recipe; the MCP is the reference. Before wiring a specific stream, load its message-schema page with searchdflow / querydocsfilesystemdflow for /resources/trading-api/websockets/{overview,quote-stream,book-stream,priority-fees-stream}. Don't guess field names.
• A DFlow API key (see "What to ASK").

In production, access to the quote and book streams is granted per key: a key that works for /order may need stream access enabled on it, so a valid key can still be refused on the stream until the team turns it on. The priority-fees stream is not gated.

Subscribe and handle frames (quote and book)

• Subscribe: { "op": "subscribe", "basemint": "<mint>", "quotemint": "<mint>" } with base58 mints, not symbols. unsubscribe mirrors it. One connection multiplexes many pairs.
• Frames batch per slot: { u: <slot>, ts, updates: [ { sb, sq, ... } ] }. Each entry in updates[] is keyed by its subject mints (sb/sq); a per-pair error arrives inline as { e: <code>, sb, sq }, which you handle without tearing down the whole feed. Load the stream's doc page for the exact per-level fields (b/a, mid, tick, cumulativesizehuman, and so on).
• Reconnect and re-subscribe. WebSockets drop; on reopen, resend every subscription with a backoff. Track the slot u (and skipped, which is 0 when the stream kept up) to detect gaps.

Priority-fees stream

The priority-fees stream works differently from quote and book: no subscribe message, just connect and read. Each message is a flat { mediumMicroLamports, highMicroLamports, veryHighMicroLamports } object (the same shape as GET /priority-fees), and this stream is not gated. Details: load /resources/trading-api/websockets/priority-fees-stream via the docs MCP.

Caveats: set expectations

Book and quote levels are approximations: the book is direct-routes-only (10 levels); quotes are direct plus one-hop, computed from a roughly $10 USDC round-trip. They can differ from the real /order quote at trade time. Don't present them as an exchange-grade order book or as the executable price. For the price a user will actually get, quote /order (see dflow-spot-trading).

What to ASK

• API key. Ask neutrally: "Do you have a DFlow API key?" It's one key for everything DFlow (the same x-api-key across the REST APIs and the WebSocket streams). Yes: prod wss://quote-api.dflow.net. No: dev wss://dev-quote-api.dflow.net (rate-limited, for testing). Prod key: https://pond.dflow.net/get-started/api-key.
• Surface. Browser or server-side? A browser app proxies through its backend (above); a server-side app connects directly with the header.

When something doesn't fit

Per-stream message schema, ping/keepalive, priority-fee fields: docs MCP (/resources/trading-api/websockets/*). Runnable reference: the DFlow order-book-visualization demo (a complete /book-stream plus proxy build), plus docs recipes /spot/recipes/stream-order-book and /spot/recipes/stream-quotes.

Sibling skills

• dflow-spot-trading: execute a swap, or take a builder platform fee. A "show live prices / order book / depth" task belongs here; a "buy / swap / convert" task belongs in dflow-spot-trading.