We’re running into a weird state issue with participant attributes during live voice calls. The goal is simple: an external Node.js service needs to read a custom attribute (ext_ref_id) from a participant, update it based on some business logic, and write it back while the call is still active.
Reading works fine. I’m using conversationsApi.getConversationParticipants and the JSON payload returns the attributes object perfectly. The problem hits when I try to PATCH it back. I’m constructing the request body exactly as the docs suggest, passing the participantId and the updated attributes object.
The API returns a 204 No Content, which usually means success. But if I immediately call GET again, the attribute is gone. Or worse, if I try to PATCH a different attribute on the same participant a second time within the same minute, I get a 409 Conflict saying the resource has been modified.
Here’s the snippet I’m using for the update:
const body = {
attributes: {
ext_ref_id: "new-value-123",
last_updated: new Date().toISOString()
}
};
await conversationsApi.patchConversationParticipant({
conversationId: convId,
participantId: partId,
body: body
});
I’ve tried:
- Adding
If-Match headers with the ETag from the GET response.
- Using the full participant object instead of just the attributes patch.
- Waiting 5 seconds between read and write.
None of it sticks. The attributes seem to be overwritten by the platform’s internal state management almost immediately after the PATCH completes. Is there a specific merge behavior I’m missing with the Node SDK? Or do I need to use the streaming API to push these updates instead of REST?
The environment is standard Node 18, genesys-cloud-nodejs-client v10.2.0. We’re in the Asia/Tokyo timezone, so maybe there’s some clock skew affecting the ETag validation, but that feels like a stretch. The logs show the 204, but the UI shows the old value. It’s driving me crazy because the basic CRUD operations work fine for conversations, but participant attributes feel like they’re in a different dimension.
You’re probably running into the classic etag mismatch or trying to patch the wrong object structure. The Node SDK’s patchConversationVoiceParticipant is strict about what you send back. It doesn’t just take a key-value pair; it expects the full participant object with the updated attributes, and you have to include the etag from the GET response. If you leave the etag out, the API rejects it to prevent race conditions.
Here’s how I usually handle this in my Node scripts. First, grab the participant and store the etag. Then, mutate the attributes object directly on the returned participant model. Finally, send it back with the etag header.
const platformClient = require('@genesyscloud/genesyscloud');
async function updateParticipantAttribute(conversationId, participantId, newExtRefId) {
const conversationsApi = platformClient.ConversationsApi;
// 1. Get the participant to fetch the current etag and state
const getResp = await conversationsApi.getConversationVoiceParticipant(conversationId, participantId);
const participant = getResp.body;
// 2. Check if attributes exist, initialize if not
if (!participant.attributes) {
participant.attributes = {};
}
// 3. Update the specific attribute
participant.attributes.ext_ref_id = newExtRefId;
// 4. Patch it back. Note the etag is crucial here.
// The SDK usually handles the If-Match header if you pass the etag from the getResp.headers,
// but explicitly setting it on the object or using the SDK's helper is safer.
const patchResp = await conversationsApi.patchConversationVoiceParticipant(
conversationId,
participantId,
participant,
{ headers: { 'If-Match': getResp.headers['etag'] } }
);
console.log("Update status:", patchResp.statusCode);
return patchResp.body;
}
If you’re still seeing the changes not stick, check the logs for a 412 Precondition Failed. That means your etag is stale. Also, make sure you’re not accidentally overwriting the entire attributes object with a partial one. The API merges, but it’s safer to just modify the existing object instance you got from the GET call.
One more thing. If you’re doing this at scale, be careful with the rate limits on the conversations API. It’s easy to hammer it if you’re looping through many participants. Maybe batch these updates if you can, or add a small delay between calls.