Calem Integration Part IV: How to Subscribe to Data Changes in Calem

Data change events and subscription are available in Calem Enterprise R2019b. Administrators can register 3^rd-party applications as listeners in Calem. These listeners are notified when records are changed in Calem.

Data change subscription and Calem REST API enable customers to build two-way integration with Calem. This blog discusses the steps to set up event listeners in Calem.

Step 1. Data Change Event

A data change event can be created for Calem to generate data change stream for a table.

• Menu path: Admin module | Open | Data Change Event
• Table name defines the table that the data change events should be generated.
• Track Attributes: use this flag to track changes of category attributes
• Track Selected: use this flag to track changes of selected base and custom fields defined in the "Field" tab.
• Optionally track edit, create and delete events.

 Step 2. Event Listeners

Event listeners are 3rd-party REST web services.

• Menu path: Admin module | Open | Data Change Listeners
• Client Id and Secret are used in the invocation of the REST web service that listens to Calem data change events.
• Client URL is the web service address.
• See Calem Enterprise API Guide for more information about authentication and JSON data encoding in building web service listeners.

• Listeners are then assigned to subscribe to events.

Step 3. Events and Notification

Once events and listeners are configured the notification process is executed periodically to send events to listeners.

• Menu path: Admin module | Open | Event Queue
• Data change events are queued for notification
• Data field can be searched by list search row

• Menu path: Admin module | Open | Event Notification
• Event notification statuses are recorded in this list for one to review what events are notified or there are errors in the notification.

Additional resources

• Calem Integration Part II: REST API
  
• Calem Enterprise REST API Guide (customer account required)
• User Guide and Admin Guide (customer account required)
• Calem Enterprise Training Site
  
• Calem Enterprise Blogs
  
• Calem Enterprise demo