Trigger fired function receives empty context.services with CREATE_COLLECTION event

Thank you VERY MUCH for your answer !!!

I tried following syntax :

try {
  // Get the target service and database info
  // TARGET_CLUSTER_NAME is defined in values, and returns exact datasource name
  const serviceName = context.values.get("PAX_TARGET_CLUSTER");
  const database = "pax";
    
  // Get service from context
  const targetsn = context.services.get(serviceName);
  console.log(`Target SN: ${JSON.stringify(targetsn, null, 2)}`);

  // Get db connection
  const targetdb = targetsn.db(database);
  console.log(`Target DB: ${JSON.stringify(targetdb, null, 2)}`);

  // Actually perform a mongo action
  // changeEvent being the payload the function receives as an argument :
  await targetdb.dropCollection(changeEvent.ns.coll);
  
} catch(err) {
  console.log("Error performing MongoDB operation:", err.message);
}

And then output is :

Target SN: {
“version”: 1
}
Target DB: {}
Error performing MongoDB operation: ‘dropCollection’ is not a function

Indeed, context.services.get(serviceName) is {}