fix(internal-plugin-metrics): log call diagsnotc milestons

Author: maxinteger

packages/@webex/internal-plugin-metrics/src/call-diagnostic/call-diagnostic-metrics.util.ts

@@ -390,6 +390,11 @@ export const prepareDiagnosticMetricItem = (webex: any, item: any) => {
 
   item.eventPayload.origin = Object.assign(origin, item.eventPayload.origin);
 
+  // Mark call milestones in logs for easier filtering and analysis
+  if (item.eventPayload.event.name) {
+    webex.logger.log(`Milestone,CallDiagnostic: ${item.eventPayload.event.name}`);
+  }
+
   webex.logger.log(
     `CallDiagnosticLatencies,prepareDiagnosticMetricItem: ${JSON.stringify({
       latencies: Object.fromEntries(cdl.latencyTimestamps),

packages/@webex/internal-plugin-metrics/test/unit/spec/call-diagnostic/call-diagnostic-metrics.util.ts

@@ -460,6 +460,33 @@ describe('internal-plugin-metrics', () => {
       });
     });
 
+    it('logs a Milestone entry when event name is present', () => {
+      const logSpy = sinon.spy(webex.logger, 'log');
+      const eventName = 'client.call.initiated';
+      const eventPayload = {event: {name: eventName}};
+
+      prepareDiagnosticMetricItem(webex, {eventPayload, type: ['diagnostic-event']});
+
+      assert.isTrue(
+        logSpy.calledWith('Milestone,CallDiagnostic', eventName),
+        'expected logger.log to be called with Milestone,CallDiagnostic and the event name'
+      );
+      sinon.restore();
+    });
+
+    it('does not log a Milestone entry when event name is absent', () => {
+      const logSpy = sinon.spy(webex.logger, 'log');
+      const eventPayload = {event: {}};
+
+      prepareDiagnosticMetricItem(webex, {eventPayload, type: ['diagnostic-event']});
+
+      assert.isFalse(
+        logSpy.calledWith('Milestone,CallDiagnostic', sinon.match.any),
+        'expected logger.log not to be called with Milestone,CallDiagnostic when event name is absent'
+      );
+      sinon.restore();
+    });
+
     it('sets buildType and upgradeChannel correctly', () => {
       const item: any = {
         eventPayload: {