Streaming API Developer Guide

Getting Started with Streaming API
Code Examples
Client Connection Considerations
PushTopic Events
Working with PushTopics
PushTopic Queries
Event Notification Rules
Replay PushTopic Streaming Events
Filtered Subscriptions
Bulk Subscriptions
Deactivating a Push Topic
PushTopic Considerations
PushTopic Streaming Allocations
Reference: PushTopic
Generic Events
Monitoring Event Usage
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Filtered Subscriptions

Reduce the number of PushTopic event notifications by specifying record fields to filter on when you subscribe to a channel.

Specify the filter criteria in an expression you append to the subscription URI, as follows.

/topic/TopicName?<expression>

TopicName is the PushTopic name, and <expression> is the expression containing one or more conditions. Join conditions with the & operator. Only the & operator is supported. Use this syntax for the <expression>.

?fieldA=valueA&fieldB=valueB&...

Include each field used in a filter condition in the PushTopic query. The & operator acts like the logical OR operator, so record events are matched if any condition is true.

Example

This subscription returns event notifications for records whose industry is Energy or shipping city is San Francisco.

The PushTopic query for this subscription includes the Industry and ShippingCity fields.

  • If you use an ID in filter criteria, use the 18-character ID format; 15-character IDs aren’t supported.
  • When using a shared CometD session with the empApi Lightning component, all subscriptions to the same PushTopic must specify the same filter. If the initial subscription doesn't use a filter, the subsequent subscriptions can't. For example, if you subscribe to /topic/MyTopic?Name='SomeName', you can’t resubscribe to /topic/MyTopic or /topic/MyTopic?Industry='Energy' using the same CometD session. Shared CometD sessions apply to subscriptions you make with the empApi Lightning component only. The empApi component shares the CometD session when you open a second instance of empApi in a new tab, or in a new browser for the same Salesforce user session.

Note