AsyncAPI channel · Alpaca · Alpaca Market Data Streaming (WebSocket)

`/v2/{feed}`

Stock market data stream. After connecting, the server sends a `[{"T":"success","msg":"connected"}]` control message. The client then sends an `auth` message, receives `[{"T":"success","msg":"authenticated"}]`, and sends `subscribe` messages. The server thereafter pushes arrays of data messages (trades, quotes, bars, etc.) for the subscribed symbols.

Open source AsyncAPI → All Alpaca channels Alpaca provider profile

Provider: Alpaca AsyncAPI: v2.6.0 Spec: Alpaca Market Data Streaming (WebSocket) Operations: 2 Messages: 10

Channel address

/v2/{feed}

Parameters

feed — The stock data feed (iex, sip, delayed_sip, test).

Operations

publish

sendStockControlMessage

Send a control message (auth, subscribe, unsubscribe).

receiveStockDataMessages

Receive streamed market data and control acknowledgements.

Messages

AuthMessage

First client message; authenticates the connection.

Content-Type: application/json

SubscribeMessage

Subscribe to one or more channels per symbol or with a wildcard.

Content-Type: application/json

UnsubscribeMessage

Remove channel subscriptions.

Content-Type: application/json

SuccessMessage

Server acknowledgement (connected / authenticated).

Content-Type: application/json

ErrorMessage

Server error (bad auth, invalid subscription, connection limit, etc.).

Content-Type: application/json

SubscriptionMessage

Server echo of the current active subscriptions after a subscribe/unsubscribe.

Content-Type: application/json

TradeMessage

A single executed trade.

Content-Type: application/json

QuoteMessage

A national best bid/offer (or crypto) quote.

Content-Type: application/json

BarMessage

An OHLCV aggregate bar (minute, daily, or updated).

Content-Type: application/json

TradingStatusMessage

A trading halt/resume or LULD status change for a symbol.

Content-Type: application/json

About AsyncAPI

The AsyncAPI specification describes event-driven APIs the way OpenAPI describes request/response APIs. A channel is the named pipe — a webhook URL, a Kafka topic, a WebSocket route, an MQTT subject — that producers and consumers publish or subscribe to. Each channel carries one or more messages with structured payloads, and an operation declares whether a given party sends or receives on that channel.

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