Streaming API Developer Guide

Getting Started with Streaming API
Push Technology
Bayeux Protocol, CometD, and Long Polling
Streaming API Terms
How the Client Connects
Message Reliability
Message Durability
Streaming Event Features
Streaming API vs. Pub/Sub API
Differences Between Change Events Received with Streaming API vs. Pub/Sub API
API End-of-Life Policy
Code Examples
Client Connection Considerations
PushTopic Events (Legacy)
Generic Events (Legacy)
Monitoring Event Usage
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Note: This release is in preview. Features described here don’t become generally available until the latest general availability date that Salesforce announces for this release. Before then, and where features are noted as beta, pilot, or developer preview, we can’t guarantee general availability within any particular time frame or at all. Make your purchase decisions only on the basis of generally available products and features.

Getting Started with Streaming API

Streaming API enables streaming of events using push technology and provides a subscription mechanism for receiving events in near real time. The Streaming API subscription mechanism supports multiple types of events, including PushTopic events, generic events, platform events, and change data capture events.

If you're writing an app for publishing and subscribing to platform events and change data capture events, we recommend you use Pub/Sub API instead of Streaming API. Pub/Sub API is a newer API. Based on gRPC API and HTTP/2, Pub/Sub API efficiently publishes and delivers binary event messages.

Important

Consider these applications for Streaming API.

Applications That Poll Frequently

Applications that have constant polling action against the Salesforce infrastructure consume unnecessary API calls and processing time. They can benefit from Streaming API because it reduces the number of requests that return no data.

General Notification

Applications that require general notification of data changes in an org. By using Streaming API, these applications can reduce the number of API calls and improve performance. You can use Streaming API with any Salesforce org as long as you enable the API. To ensure continuity during instance refreshes and org migrations, we recommend using your org’s My Domain login URL instead of its instance in the Streaming API endpoint.