Create or Modify Counters

Flow:

• Open a session.
• Create an instance of countersFor.
  • Either pass countersFor an explicit document ID, -or-
  • Pass it an entity tracked by the session, e.g. a document object returned from session.query or from session.load.
• Call countersFor.increment.
• Call session.saveChanges for the changes to take effect.

Note:

• Modifying a Counter using increment only takes effect when session.saveChanges() is executed.
• To decrease a Counter's value, pass the method a negative number to the increment method.

// Open a session
const session = documentStore.openSession();        
       
// Pass a document ID to the countersFor constructor 
const documentCounters = session.countersFor("products/1-A");

// Use `countersFor.increment`:
// ============================

// Increase "ProductLikes" by 1, or create it if doesn't exist with a value of 1
documentCounters.increment("ProductLikes", 1); 

// Increase "ProductPageViews" by 15, or create it if doesn't exist with a value of 15
documentCounters.increment("ProductPageViews", 15);

// Decrease "DaysLeftForSale" by 10, or create it if doesn't exist with a value of -10
documentCounters.increment("DaysLeftForSale", -10);

// Save changes
await session.saveChanges();

increment(counter);
increment(counter, delta);