The Salesforce Streaming API is used when you need to keep your external source in sync with the Salesforce data with PushTopic events and Change Data Capture events.
Streaming API uses Bayeux Protocol and Asynchronous in Nature.
Data Format is JSON.
Use Streaming API to receive near-real-time streams of data that are based on changes in salesforce records or custom payloads. If a salesforce record changes,salesforce publishes notifications when the changes occur.
- Push Topic Event.
- Change Data Capture Event.
Let us Discuss One by One with Example
Receive changes to Salesforce records based on a SOQL Query that you define.The notifications include only the fields that you specify in the SOQL query.
Push Topic Implementation
Select PushTopic from Object type. Click Next.
Click confirm Insert.
Select the created Push Topic Name in the dropdown and then Subscribe.
It will show connection Established Successful in Json.
In the dropdown,select Queries and click streaming pushtopics.
This is the SOQL Query we used to implement the pushTopic Event
SELECT Id, StageName , CloseDate from Opportunity where CloseDate=TODAY
This is the created record based on the Query.
- Receive Changes to salesforce records with all changed fields.Change data capture supports more standard objects than pushTopic Events and provides more Features.
- Changes include creation of a new record,updates to an exsisting record,deletion of a record,undeletion of a record.
- The objects can be selected through UI, for publishing events.
- The CDC supports for all custom and standard objects.
- The channel for subscription for standard object /data/<Standard_object_Name>
- Example: /data/ContactChangeEvent
- The channel for subscription for custom Object /data/<Custom_object_Name>__ChangeEvent
- Example: /data/Employee__ChangeEvent
In quick find, search Change Data Capture.
Select objects from Available entities to standard entities click save.
In queries dropdown,select Streaming Push Topics
In Subscriptions, Enter /data/ContactChangeEvent.
The contact record is created.
And the same record is updated.