Package markets.alpaca.client.ws

Class AlpacaNewsStream

java.lang.Object

markets.alpaca.client.ws.internal.AbstractAlpacaStream

markets.alpaca.client.ws.internal.AbstractMarketDataStream

markets.alpaca.client.ws.AlpacaNewsStream

All Implemented Interfaces:

AutoCloseable

public final class AlpacaNewsStream
extends AbstractMarketDataStream

WebSocket client for the Alpaca real-time news stream (/v1beta1/news).

Usage

 var stream = AlpacaClientFactory.newsStream(
     creds,
     AlpacaStreamEnvironment.PRODUCTION,
     new NewsStreamListener() {
         @Override public void onArticle(NewsArticle a) { System.out.println(a.headline()); }
     });

 stream.connect(NewsSubscription.builder().symbols("AAPL", "TSLA").build());
 

Only available on the production endpoint. Use "*" as a symbol to receive news for all available symbols.

Field Summary

Fields inherited from class markets.alpaca.client.ws.internal.AbstractMarketDataStream

GSON

Constructor Summary

Constructors

Constructor	Description
AlpacaNewsStream(okhttp3.OkHttpClient httpClient, AlpacaCredentials credentials, String url, NewsStreamListener listener)	Creates a new news stream client for a custom WebSocket URL.
AlpacaNewsStream(okhttp3.OkHttpClient httpClient, AlpacaCredentials credentials, AlpacaStreamEnvironment environment, NewsStreamListener listener)	Creates a new news stream client.
AlpacaNewsStream(okhttp3.OkHttpClient httpClient, AlpacaCredentials credentials, AlpacaStreamEnvironment environment, NewsStreamListener listener, AlpacaStreamReconnectPolicy reconnectPolicy)	Creates a new news stream client with a custom reconnect policy.
AlpacaNewsStream(okhttp3.OkHttpClient httpClient, AlpacaCredentials credentials, AlpacaStreamEnvironment environment, NewsStreamListener listener, AlpacaStreamReconnectPolicy reconnectPolicy, Executor callbackExecutor)	Creates a new news stream client with a custom reconnect policy and listener executor.

Method Summary

Modifier and Type	Method	Description
protected okhttp3.Request	buildRequest()	Builds the WebSocket upgrade request (URL + any auth headers).
void	connect(NewsSubscription sub)	Opens the stream and subscribes after authentication completes.
protected void	dispatchDataMessage(com.google.gson.JsonObject msg, String type)	Called for each data message element with a non-control T value.
protected void	handleMarketDataClose(int code, String reason, boolean willReconnect)
protected void	notifyAuthenticated()
protected void	notifyConnected()
protected void	notifyError(int code, String message)
protected void	notifyReconnected()	Called after a reconnect attempt succeeds and the stream is fully re-authenticated (and re-subscribed, if applicable).
protected void	notifyReconnecting(int attempt)	Called just before a reconnect attempt is initiated.
protected void	notifySubscriptionConfirmed(Map<String,List<String>> subscriptions)
void	subscribe(NewsSubscription sub)	Subscribes to news for the given symbols.
void	unsubscribe(NewsSubscription sub)	Unsubscribes from news for the given symbols.

Methods inherited from class markets.alpaca.client.ws.internal.AbstractMarketDataStream

getConfirmedSubscriptions, handleClose, handleOpen, handleText, resubscribeAfterAuth, sendSubscriptionMessage

Methods inherited from class markets.alpaca.client.ws.internal.AbstractAlpacaStream

authenticationFuture, authenticationResultFuture, close, closeTerminal, closeTerminal, completeAuthentication, completeAuthentication, connect, handleBytes, invokeCallback, isClosed, isReconnecting, requireOpenForCommand, resetReconnectAttempts, send, waitForAuthentication, waitForAuthenticationResult

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

AlpacaNewsStream

public AlpacaNewsStream(okhttp3.OkHttpClient httpClient,
 AlpacaCredentials credentials,
 AlpacaStreamEnvironment environment,
 NewsStreamListener listener)

Creates a new news stream client. Use AlpacaClientFactory.newsStream(markets.alpaca.client.AlpacaCredentials, markets.alpaca.client.ws.AlpacaStreamEnvironment, markets.alpaca.client.ws.NewsStreamListener) rather than calling this constructor directly.

AlpacaNewsStream

public AlpacaNewsStream(okhttp3.OkHttpClient httpClient,
 AlpacaCredentials credentials,
 AlpacaStreamEnvironment environment,
 NewsStreamListener listener,
 AlpacaStreamReconnectPolicy reconnectPolicy)

Creates a new news stream client with a custom reconnect policy. Use AlpacaClientFactory.newsStream(markets.alpaca.client.AlpacaCredentials, markets.alpaca.client.ws.AlpacaStreamEnvironment, markets.alpaca.client.ws.NewsStreamListener) rather than calling this constructor directly.

AlpacaNewsStream

public AlpacaNewsStream(okhttp3.OkHttpClient httpClient,
 AlpacaCredentials credentials,
 AlpacaStreamEnvironment environment,
 NewsStreamListener listener,
 AlpacaStreamReconnectPolicy reconnectPolicy,
 Executor callbackExecutor)

Creates a new news stream client with a custom reconnect policy and listener executor. Use AlpacaClientFactory.newsStream(markets.alpaca.client.AlpacaCredentials, markets.alpaca.client.ws.AlpacaStreamEnvironment, markets.alpaca.client.ws.NewsStreamListener) rather than calling this constructor directly.

AlpacaNewsStream

public AlpacaNewsStream(okhttp3.OkHttpClient httpClient,
 AlpacaCredentials credentials,
 String url,
 NewsStreamListener listener)

Creates a new news stream client for a custom WebSocket URL.

Method Details

buildRequest

protected okhttp3.Request buildRequest()

Description copied from class: AbstractAlpacaStream

Builds the WebSocket upgrade request (URL + any auth headers).

Specified by:

buildRequest in class AbstractAlpacaStream

handleMarketDataClose

protected void handleMarketDataClose(int code,
 String reason,
 boolean willReconnect)

Specified by:

handleMarketDataClose in class AbstractMarketDataStream

notifyReconnecting

protected void notifyReconnecting(int attempt)

Description copied from class: AbstractAlpacaStream

Called just before a reconnect attempt is initiated.

Overrides:

notifyReconnecting in class AbstractAlpacaStream

Parameters:

attempt - 1-based attempt counter

notifyConnected

protected void notifyConnected()

Specified by:

notifyConnected in class AbstractMarketDataStream

notifyAuthenticated

protected void notifyAuthenticated()

Specified by:

notifyAuthenticated in class AbstractMarketDataStream

notifySubscriptionConfirmed

protected void notifySubscriptionConfirmed(Map<String,List<String>> subscriptions)

Specified by:

notifySubscriptionConfirmed in class AbstractMarketDataStream

notifyError

protected void notifyError(int code,
 String message)

Specified by:

notifyError in class AbstractMarketDataStream

notifyReconnected

protected void notifyReconnected()

Description copied from class: AbstractAlpacaStream

Called after a reconnect attempt succeeds and the stream is fully re-authenticated (and re-subscribed, if applicable). Default implementation is a no-op.

Overrides:

notifyReconnected in class AbstractAlpacaStream

dispatchDataMessage

protected void dispatchDataMessage(com.google.gson.JsonObject msg,
 String type)

Description copied from class: AbstractMarketDataStream

Called for each data message element with a non-control T value.

Specified by:

dispatchDataMessage in class AbstractMarketDataStream

Parameters:

msg - the JSON object for this message

type - the T field value (e.g. "t", "q", "b")

subscribe

public void subscribe(NewsSubscription sub)

Subscribes to news for the given symbols. Additive. Use NewsSubscription.builder().symbols("*").build() for all symbols.

connect

public void connect(NewsSubscription sub)

Opens the stream and subscribes after authentication completes.

This is equivalent to calling subscribe(NewsSubscription) before AbstractAlpacaStream.connect(); the subscription is buffered until the server accepts the credentials.

unsubscribe

public void unsubscribe(NewsSubscription sub)

Unsubscribes from news for the given symbols.