Stream Data Using SSE#

We stream data using Server-Sent Events (SSE). We provide endpoints for streaming the following types of data:

US stocks and securities
Forex / currencies
News
Social sentiment
IEX Tops
IEX Last
IEX Deep

The endpoints are available via the IEX Cloud Legacy API and described in the Legacy API Reference.

How Credits Work with Streaming#

For Apperate plans, each message received over the stream counts as a read.

1 million reads = 1 credit

Important

Unlike other cloud databases that charge based on table scans and/or data blocks, a read on Apperate equates to getting a whole record/row.

US Stocks and Securities#

There are three types of endpoints for US stocks and securities. Two of them require a paid plan and a UTP agreement. Here’s an overview of these endpoints:

US Stocks Endpoints:

Endpoint	Response Data	Requirements
`stocksUS`	- IEX real-time data - 15 min delayed Nasdaq listed data (UTP) - 15 min delayed NYSE listed data (CTA)	- Paid plan - UTP agreement
`stocksUSNoUTP`	- IEX real-time data - 15 min delayed NYSE listed data (CTA)	None
`stocksOTC`	- 15 min delayed OTC data	- Paid plan - UTP agreement with OTC eligibility

Get Nasdaq-listed Stock Data (UTP/OTC Data) explains the UTP agreement process.

Firehose Versus Streaming on Symbols#

You can stream on specific symbols or stream everything – like drinking from a firehose.

The symbols query parameter enables you to stream on a specific symbol or comma-separated list of symbols. The examples below respectively demonstrate calling the stocksUS endpoint on specific symbols and all symbols.

Stream on symbols:

curl --header 'Accept: text/event-stream' 'https://cloud-sse.iexapis.com/v1/stocksUS?symbols=spy,msft&token=YOUR_TOKEN'

Firehose:

curl --header 'Accept: text/event-stream' 'https://cloud-sse.iexapis.com/v1/stocksUS?token=YOUR_TOKEN'

You can use the symbols parameter with all the streaming endpoints.

Note

Firehose functionality does not apply to IEX DEEP streaming endpoints.

Snapshots#

When you connect to an SSE endpoint, you receive a snapshot of the latest message and then receive updates as they are available. You can disable snapshots by using the query parameter setting nosnapshot=true.

You can also specify a starting point for a snapshot by using a query parameter setting snapshotAsOf=EPOCH_TIMESTAMP, where the value is in milliseconds since Epoch.

Interval Streaming#

Some data is available to stream at set intervals: 1 second, 5 seconds, or 1 minute. This helps make data delivery and credit usage more predictable. The endpoints below, for example, compliment the stocksUS endpoint.

1 second interval:

curl --header 'Accept: text/event-stream' 'https://cloud-sse.iexapis.com/v1/stocksUS1Second?token=YOUR_TOKEN&symbols=spy'

5 second interval:

curl --header 'Accept: text/event-stream' 'https://cloud-sse.iexapis.com/v1/stocksUS5Second?token=YOUR_TOKEN&symbols=spy'

1 minute interval:

curl --header 'Accept: text/event-stream' 'https://cloud-sse.iexapis.com/v1/stocksUS1Minute?token=YOUR_TOKEN&symbols=spy'

What’s Next#

Now you’re familiar with some of the SSE Streaming endpoints. You can try more SSE Streaming endpoints as described in the Legacy API Reference.