Stumbled on a weird bug today with how I’m flattening the v2.analytics.conversation.aggregate event payload from EventBridge.
I’m building a consumer to sync conversation metrics back to our identity platform for audit trails, but the metrics array is nested inside the aggregations object, and the structure seems to shift slightly depending on whether the conversation was voice or digital.
Here’s the snippet I’m using to extract the duration:
for agg in payload['aggregations']:
for metric in agg.get('metrics', []):
if metric['metric'] == 'conversation.duration':
return metric['value']
The code works fine for voice, but for digital conversations, the metric key sometimes appears as name or the value is buried deeper in a stats object. Am I missing a standard schema definition for this specific event type, or is this a known inconsistency in the v2 analytics webhooks? I don’t want to write brittle conditional logic for every possible channel type.
This seems like a classic schema drift issue when aggregating voice and digital channels. The v2.analytics.conversation.aggregate payload isn’t static; it morphs based on the media type. If you’re hardcoding paths for aggregations.metrics, you’ll break on digital conversations where metrics might be nested differently or absent entirely.
Instead of trying to flatten this in the consumer Lambda, shift the normalization upstream using an EventBridge rule with a pattern match, or better yet, use a Step Function to handle the branching logic. But if you want to keep it simple in Node.js, don’t iterate blindly. Check the type field first.
Here’s a robust extraction pattern I use in my CDK-deployed Lambdas. It handles the optional chaining safely and normalizes the output regardless of media type:
const normalizeMetrics = (payload) => {
const type = payload.type; // 'voice' or 'digital'
const agg = payload.aggregations || {};
// Voice often has distinct wait and talk metrics
if (type === 'voice') {
return {
waitTime: agg.waitTime?.value || 0,
talkTime: agg.talkTime?.value || 0,
holdTime: agg.holdTime?.value || 0
};
}
// Digital usually bundles into interactionDuration
if (type === 'digital') {
return {
interactionDuration: agg.interactionDuration?.value || 0,
agentResponseTime: agg.agentResponseTime?.value || 0
};
}
return {};
};
Also, watch out for the partition field in the aggregate event. If you’re syncing to an identity platform, ensure you’re keying off the conversationId and not just the timestamp, as aggregates can fire multiple times if the conversation spans multiple queues. This prevents duplicate audit trails. Keep the Lambda cold start low by bundling the SDK in a layer, but the logic above is the critical fix for the nested array issue.