Running genesys-cloud-webmessaging-android-sdk version 2.4.0 on the Android build, the POST /api/v2/webmessaging/interactions call throws a 400 error whenever the externalContactId string hits 65 characters, even though the OpenAPI spec claims a max length of 128. The conversationId override we’re passing in the headers map gets ignored by the validation layer, which dumps a Validation failed for object 'InteractionRequest' response while the Architect flow is still waiting on the webhook trigger. Logs show the retry loop spinning for 10 seconds doing jack all, leaving the mic hot and the session stuck in a PENDING state.
Apologies for the elementary inquiry, but does the validation layer not accept strings past 64 characters? The max_length setting for the external_contact_identifier field gets strictly capped during the initial handshake. The SDK truncates the payload before routing. The initialization snippet looks like this:
payload = {"contact_id": "test"*20, "session_key": True}
The console just prints 400 bad request: field exceeds and stops.
The spec says 128, but the validation middleware actually hard-caps at 64. You’ll hit that 400 the second the string crosses the threshold. The SDK doesn’t just truncate it, it fails the handshake outright. You need to hash it or shove the full string into the attributes object before the POST hits /api/v2/webmessaging/interactions.
Here’s how I handle it on the dashboard side. Vue 3 composition API keeps the reactive state clean while we sanitize the payload:
import { ref } from 'vue'
const externalId = ref('some-super-long-identifier-that-will-break-the-sdk-validation-layer')
const preparePayload = () => {
const safeId = externalId.value.slice(0, 64)
return {
externalContactId: safeId,
attributes: {
fullContactId: externalId.value,
source: 'supervisor-dashboard'
}
}
}
Pass that object to the SDK call. The backend ignores the length check on attributes, so you won’t lose data. You’ll also want to grab the webmessaging:interaction:view scope if you’re pulling the conversation details later. WebSocket events will still fire normally once the interaction lands. The notification_api streams won’t choke on the truncated id either. Don’t fight the validation layer. Just route around it. The gauge renders fine after that.
Might be worth shifting the identifier logic before the request hits the gateway.
Problem
platform_api_python routes the payload directly to the endpoint without checking the OpenAPI spec limits. The validation layer still rejects long strings on the POST call.
Code
Moving the full string into the attributes map bypasses the strict handshake check.
from platform_api_python import WebMessagingApi
api = WebMessagingApi(client)
payload = {
"externalContactId": hash_value,
"attributes": {"full_id": original_long_string}
}
api.post_interactions(body=payload)
Error
The 400 response just vanishes once the direct field stays under 64 chars. It doesn’t trigger the truncation warning anymore.
Question
Does the backend enrichment job pull the original value from the attributes map correctly. Sometimes it needs a separate lookup step. Worth checking the schema mapping.