What are streaming APIs? Description and examples

Streaming APIs are used to examine data in real time so users can gather up-to-date information and accurate results through the web. This process starts with a consumer or client opening a socket, one side of a two-way communications link. Then, through that socket, certain data criteria can be received.

To better understand the nature of streaming APIs, we can look to their opposite counterpart, REST APIs, as a point of comparison.

The dividing line between REST APIs and streaming APIs

REST APIs operate in a client-server architecture where they follow a flow of “request and response.” A user makes a request, and the server responds with the information the user wants to obtain. The two servers work independently from one another.

Streaming APIs essentially flip the script on this conversational-style format. In the case of streaming APIs, updates are sent to the consumer/client when an event happens.

The logic behind streaming APIs is the same as the video in an online broadcast. Data trickles in little by little, in real time, as it’s generated or captured. This produces a continuous experience for users.

Note: there can be some confusion between event-driven and streaming APIs. This blog gives a good overview of how they overlap and where they differ.

By nature, REST APIs are stateless. Each request is self-contained. It is addressed based entirely on the information that comes with the request and can be understood in isolation.

In contrast, streaming APIs are stateful. Requests are handled in the context of prior transactions, with the same servers used each time to process said requests. Data must be stored in some form so streaming APIs can properly scrutinize and analyze the basic data correlation with the user making the request.

See also: event-driven APIs vs REST APIs.

Why streaming APIs are important

The value of streaming APIs lies in having a pulse on the quickest way to deliver data to users. Information is provided to clients or consumers as soon as it occurs, eliminating wait times and, in doing so, boosting user engagement most efficiently.

The added benefit of streaming APIs is that they function as a radar for your data, reducing the number of requests that will yield no data. This reduction in requests lends itself to a faster load time for your website and, in turn, a better user experience.

Interestingly, streaming APIs can be less of a drain on networks, servers, and devices, since they only send an update when there is an update. Read more about sustainable IT and energy-efficient APIs here.

Learn more about an open approach to API management that goes beyond just SOAP and REST APIs (such as events or GraphQL).

Examples of streaming APIs

Streaming APIs have become an integral part of today’s data-driven landscape. These streaming data examples span banking, ride-sharing, logistics, messaging, and connected homes.

Let’s start with an open banking example. When a user goes to check on the health of their bank accounts via a third-party provider app, a streaming API can deliver real-time information. API calls are only submitted if the data has changed.

Users get the up-to-date information they want while the provider prevents wasted API calls. Financial institutions apply the same direct streaming of transaction messages API pattern to push payment events to partners.

Another way to think about this is through the lens of a ride-share service like Uber. Its streaming APIs update users about a driver’s location and how long it will be before they arrive at the pick-up destination.

These interactions create a smoother experience for users, making them more likely to engage with the API again.

While on the topic of transportation, logistics and automotive companies need to track fleets and shipments in real time. Streaming APIs create a continuous connection to share live data with the user until they close that connection, without significant latency.

From these added insights, industry professionals can easily monitor vehicle activities while identifying ways to best plan for and adapt routes for efficiency and satisfaction.

Here are a few additional real-world cases to add to this streaming API example list:

• Slack’s streaming messaging API ensures the most recent, relevant conversations within a user’s messaging applications are available at their fingertips.
• Blockchain streaming APIs push real-time market information to users so they can stay informed on changes, trends, and fluctuations in a volatile market.
• Nest’s streaming API allows API consumers to listen for changes in their home thermostats, alarms, and security cameras versus polling the REST API for new information.

API management is evolving. See why experts recommend modern enterprises adopt a more flexible and adaptable approach.

Streaming API protocols and techniques

Developers choosing APIs for streaming pick from five main techniques.

A REST API streaming data approach, such as long polling, still works for smaller workloads. Purpose-built channels handle scale better. Managing REST and event endpoints together is where a federated API management approach pays off.

Streaming APIs and hybrid integration

Most organizations in business today have extensive legacy systems, built on synchronous mechanisms such as REST APIs. Unfortunately, there’s no easy way to integrate these newer events and streaming APIs with the synchronous mechanisms already in place.

That’s why Amplify Fusion is a purpose-built integration solution that extends your API management with event-driven integration built in. There is no need to rip and replace what is already there. Amplify Fusion extends and modernizes your existing solution.

Orchestrate, automate, and manage end-to-end workflows, event-based or not.

Streaming API FAQs

What is an API stream? An API stream is a persistent connection that pushes data to the client as events happen. Consumers subscribe to an API data stream instead of polling for changes. A real-time data streaming API removes wasted requests entirely. That is why the API streaming model scales so well.

What separates a streaming API vs REST API? A REST API answers one request at a time. A streaming API holds the connection open and pushes updates as they happen. People search the rest api vs streaming api question both ways, and the tradeoffs are identical.

Can a REST API stream data? Yes, within limits. REST API streaming data techniques like long polling and server-sent events imitate a streaming REST API. A live streaming rest api hybrid is common while teams migrate to event channels.

Which streaming services with public API access can developers try? Streaming services with public API access include Spotify, Twitch, and YouTube Live. A live streaming API for video solves a different problem from data event feeds like Slack’s messaging stream.

How does stream API testing work? Stream API testing checks the connection lifecycle, message ordering, and reconnection behavior. Teams replay recorded event sequences against the stream API endpoint and assert on received messages.