Building a Custom NICE CXone Data Actions Destination Sink in Node.js

What You Will Build

• A Node.js microservice that connects to a NICE CXone Data Actions WebSocket stream, validates incoming interaction events against strict JSON schemas, and writes them to a PostgreSQL database using idempotent upserts inside database transactions.
• This implementation uses the NICE CXone Data Actions WebSocket API and the OAuth 2.0 Client Credentials flow.
• The code covers Node.js (ES modules) with ws, ajv, and pg.

Prerequisites

• OAuth Client Credentials grant configured in CXone with data-actions:read scope
• CXone Data Action stream configured to output JSON events to a WebSocket endpoint
• Node.js 18+
• PostgreSQL 14+
• Dependencies: ws@8.16.0, ajv@8.12.0, pg@8.11.3, dotenv@16.3.1
• Database table structure matching the target schema (provided in Step 3)

Authentication Setup

CXone requires a valid OAuth 2.0 Bearer token for WebSocket handshake headers and initial stream authentication. The Client Credentials flow returns a token valid for 3600 seconds. The following code fetches the token, caches it, and implements retry logic for 429 rate-limit responses.

import fetch from 'node-fetch';
import dotenv from 'dotenv';

dotenv.config();

const OAUTH_URL = 'https://api.cxp.cxone.com/oauth/token';
const CLIENT_ID = process.env.CXONE_CLIENT_ID;
const CLIENT_SECRET = process.env.CXONE_CLIENT_SECRET;

let cachedToken = null;
let tokenExpiry = 0;

async function acquireConeToken(retryCount = 0) {
  if (cachedToken && Date.now() < tokenExpiry) {
    return cachedToken;
  }

  const payload = new URLSearchParams({
    grant_type: 'client_credentials',
    client_id: CLIENT_ID,
    client_secret: CLIENT_SECRET,
    scope: 'data-actions:read'
  });

  try {
    const response = await fetch(OAUTH_URL, {
      method: 'POST',
      headers: {
        'Content-Type': 'application/x-www-form-urlencoded'
      },
      body: payload
    });

    if (response.status === 429 && retryCount < 3) {
      const retryAfter = parseInt(response.headers.get('Retry-After') || '5', 10);
      await new Promise(resolve => setTimeout(resolve, retryAfter * 1000));
      return acquireConeToken(retryCount + 1);
    }

    if (!response.ok) {
      const errorBody = await response.text();
      throw new Error(`OAuth token request failed with status ${response.status}: ${errorBody}`);
    }

    const data = await response.json();
    cachedToken = data.access_token;
    tokenExpiry = Date.now() + (data.expires_in * 1000) - 30000; // Refresh 30s early
    return cachedToken;
  } catch (error) {
    if (error.code === 'ENOTFOUND' || error.message.includes('ECONNREFUSED')) {
      throw new Error('Network unreachable. Verify CXone endpoint connectivity.');
    }
    throw error;
  }
}

// Initial fetch to prime cache
await acquireConeToken();

OAuth Scope Requirement: data-actions:read is mandatory. The client_credentials grant type does not require a redirect URI. The response body contains access_token, token_type, expires_in, and scope.

Implementation

Step 1: Initialize WebSocket Connection with Token Injection

CXone Data Actions streams authenticate via the Authorization header during the WebSocket handshake. The connection must handle token expiration by reconnecting when the server closes the stream or returns an authentication error.

import WebSocket from 'ws';

const STREAM_ID = process.env.CXONE_STREAM_ID;
const WS_URL = `wss://api.cxp.cxone.com/data-actions/v1/stream/${STREAM_ID}`;

async function createDataActionStream() {
  const token = await acquireConeToken();
  
  const ws = new WebSocket(WS_URL, {
    headers: {
      'Authorization': `Bearer ${token}`,
      'Accept': 'application/json'
    }
  });

  return ws;
}

// Connection state management
let connection = null;
let isReconnecting = false;

async function startStream() {
  connection = await createDataActionStream();

  connection.on('open', () => {
    console.log('WebSocket connection established to CXone Data Actions.');
  });

  connection.on('close', (code, reason) => {
    console.log(`WebSocket closed: ${code} ${reason}`);
    if (!isReconnecting && code !== 1000) {
      scheduleReconnect();
    }
  });

  connection.on('error', (error) => {
    console.error('WebSocket error:', error.message);
    if (error.message.includes('401') || error.message.includes('403')) {
      cachedToken = null; // Invalidate cache to force refresh on reconnect
    }
  });
}

function scheduleReconnect() {
  isReconnecting = true;
  const delay = Math.min(1000 * Math.pow(2, Math.random()), 30000);
  setTimeout(async () => {
    isReconnecting = false;
    try {
      await startStream();
    } catch (err) {
      console.error('Reconnection failed:', err.message);
      scheduleReconnect();
    }
  }, delay);
}

Expected Behavior: The WebSocket opens with status 101. If the token expires during the session, CXone closes the connection with code 4001 or 1008. The retry logic invalidates the cached token, fetches a fresh one, and re-establishes the stream.

Step 2: Configure Ajv Validation for CXone Event Schemas

Data Actions payloads vary by stream configuration. The following Ajv configuration enforces strict typing, rejects unknown keys, and validates timestamps. This prevents malformed CXone events from corrupting the database.

import Ajv from 'ajv';
import addFormats from 'ajv-formats';

const ajv = new Ajv({ allErrors: true, strict: true });
addFormats(ajv);

const cxoneEventSchema = {
  type: 'object',
  required: ['interactionId', 'timestamp', 'type', 'idempotencyKey'],
  additionalProperties: false,
  properties: {
    interactionId: { type: 'string', minLength: 1 },
    timestamp: { type: 'string', format: 'date-time' },
    type: { type: 'string', enum: ['call', 'chat', 'email', 'callback'] },
    idempotencyKey: { type: 'string', pattern: '^[a-zA-Z0-9_-]+$' },
    attributes: {
      type: 'object',
      additionalProperties: true,
      properties: {
        duration: { type: ['number', 'null'] },
        disposition: { type: ['string', 'null'] },
        queueName: { type: ['string', 'null'] },
        agentId: { type: ['string', 'null'] }
      }
    }
  }
};

const validateCxoneEvent = ajv.compile(cxoneEventSchema);

function validateAndSanitizeEvent(rawPayload) {
  const isValid = validateCxoneEvent(rawPayload);
  
  if (!isValid) {
    const errors = validateCxoneEvent.errors.map(err => 
      `${err.instancePath} ${err.message}`
    ).join('; ');
    console.warn('Schema validation failed:', errors);
    return null;
  }

  // Normalize nested attributes to flat structure for DB insertion
  const { attributes, ...baseEvent } = rawPayload;
  return {
    ...baseEvent,
    duration: attributes?.duration ?? null,
    disposition: attributes?.disposition ?? null,
    queue_name: attributes?.queueName ?? null,
    agent_id: attributes?.agentId ?? null
  };
}

Non-Obvious Parameters: The additionalProperties: false flag rejects any unexpected CXone fields. The idempotencyKey pattern ensures database uniqueness. The format: 'date-time' validation leverages RFC 3339 parsing, which matches CXone ISO 8601 outputs.

Step 3: Implement PostgreSQL Transactional Upserts with Idempotency

Idempotent upserts prevent duplicate records when CXone retries event delivery. The following code uses a database transaction, ON CONFLICT handling, and explicit column mapping to guarantee data consistency.

import pg from 'pg';

const { Pool } = pg;
const dbPool = new Pool({
  host: process.env.DB_HOST,
  port: parseInt(process.env.DB_PORT || '5432', 10),
  database: process.env.DB_NAME,
  user: process.env.DB_USER,
  password: process.env.DB_PASSWORD,
  max: 10,
  idleTimeoutMillis: 30000,
  connectionTimeoutMillis: 5000
});

// DDL for reference (run once externally):
/*
CREATE TABLE IF NOT EXISTS cxone_events (
  id SERIAL PRIMARY KEY,
  interaction_id VARCHAR(255) NOT NULL,
  timestamp TIMESTAMP WITH TIME ZONE NOT NULL,
  type VARCHAR(50) NOT NULL,
  idempotency_key VARCHAR(255) UNIQUE NOT NULL,
  duration INTEGER,
  disposition VARCHAR(255),
  queue_name VARCHAR(255),
  agent_id VARCHAR(255),
  created_at TIMESTAMP WITH TIME ZONE DEFAULT NOW(),
  updated_at TIMESTAMP WITH TIME ZONE DEFAULT NOW()
);
*/

async function upsertEventTransaction(event) {
  const client = await dbPool.connect();
  
  try {
    await client.query('BEGIN');

    const insertQuery = `
      INSERT INTO cxone_events 
        (interaction_id, timestamp, type, idempotency_key, duration, disposition, queue_name, agent_id, updated_at)
      VALUES ($1, $2, $3, $4, $5, $6, $7, $8, NOW())
      ON CONFLICT (idempotency_key) 
      DO UPDATE SET
        duration = EXCLUDED.duration,
        disposition = EXCLUDED.disposition,
        queue_name = EXCLUDED.queue_name,
        agent_id = EXCLUDED.agent_id,
        updated_at = NOW()
      RETURNING id, updated_at;
    `;

    const values = [
      event.interactionId,
      event.timestamp,
      event.type,
      event.idempotencyKey,
      event.duration,
      event.disposition,
      event.queue_name,
      event.agent_id
    ];

    const result = await client.query(insertQuery, values);
    await client.query('COMMIT');
    
    console.log(`Event ${event.idempotencyKey} processed. DB record ID: ${result.rows[0].id}`);
    return result.rows[0];
  } catch (error) {
    await client.query('ROLLBACK');
    
    if (error.code === '23505') {
      console.warn('Unique constraint violation during upsert:', error.detail);
    } else if (error.code === '23503') {
      console.warn('Foreign key constraint violation:', error.detail);
    } else {
      console.error('Database transaction failed:', error.message);
    }
    
    throw error;
  } finally {
    client.release();
  }
}

Transactional Integrity: The BEGIN/COMMIT block ensures partial writes never occur. If the ON CONFLICT clause triggers, the DO UPDATE branch modifies only the specified columns. The EXCLUDED pseudo-table references the incoming values. The client.release() call in the finally block returns the connection to the pool regardless of success or failure.

Step 4: Wire the Message Pipeline

The final step connects the WebSocket message handler to validation and database insertion. The pipeline batches errors and continues processing to prevent a single malformed event from halting the stream.

async function attachMessageHandler(ws) {
  ws.on('message', async (data) => {
    try {
      const rawEvent = JSON.parse(data.toString());
      
      const normalizedEvent = validateAndSanitizeEvent(rawEvent);
      if (!normalizedEvent) {
        console.warn('Dropped invalid event:', rawEvent);
        return;
      }

      await upsertEventTransaction(normalizedEvent);
    } catch (error) {
      console.error('Pipeline processing error:', error.message);
      // Do not crash the stream. Log and continue.
    }
  });
}

Complete Working Example

The following script combines authentication, WebSocket management, validation, and database operations into a single executable module. Create a .env file with the required variables and run node sink.js.

import 'dotenv/config';
import WebSocket from 'ws';
import Ajv from 'ajv';
import addFormats from 'ajv-formats';
import { Pool } from 'pg';
import fetch from 'node-fetch';

// Configuration
const OAUTH_URL = 'https://api.cxp.cxone.com/oauth/token';
const WS_URL = `wss://api.cxp.cxone.com/data-actions/v1/stream/${process.env.CXONE_STREAM_ID}`;
const CLIENT_ID = process.env.CXONE_CLIENT_ID;
const CLIENT_SECRET = process.env.CXONE_CLIENT_SECRET;

// OAuth State
let cachedToken = null;
let tokenExpiry = 0;

// Database Pool
const dbPool = new Pool({
  host: process.env.DB_HOST,
  port: parseInt(process.env.DB_PORT || '5432', 10),
  database: process.env.DB_NAME,
  user: process.env.DB_USER,
  password: process.env.DB_PASSWORD,
  max: 10,
  idleTimeoutMillis: 30000,
  connectionTimeoutMillis: 5000
});

// Ajv Validator
const ajv = new Ajv({ allErrors: true, strict: true });
addFormats(ajv);

const cxoneEventSchema = {
  type: 'object',
  required: ['interactionId', 'timestamp', 'type', 'idempotencyKey'],
  additionalProperties: false,
  properties: {
    interactionId: { type: 'string', minLength: 1 },
    timestamp: { type: 'string', format: 'date-time' },
    type: { type: 'string', enum: ['call', 'chat', 'email', 'callback'] },
    idempotencyKey: { type: 'string', pattern: '^[a-zA-Z0-9_-]+$' },
    attributes: {
      type: 'object',
      additionalProperties: true,
      properties: {
        duration: { type: ['number', 'null'] },
        disposition: { type: ['string', 'null'] },
        queueName: { type: ['string', 'null'] },
        agentId: { type: ['string', 'null'] }
      }
    }
  }
};

const validateCxoneEvent = ajv.compile(cxoneEventSchema);

// Core Functions
async function acquireConeToken(retryCount = 0) {
  if (cachedToken && Date.now() < tokenExpiry) return cachedToken;

  const payload = new URLSearchParams({
    grant_type: 'client_credentials',
    client_id: CLIENT_ID,
    client_secret: CLIENT_SECRET,
    scope: 'data-actions:read'
  });

  try {
    const response = await fetch(OAUTH_URL, {
      method: 'POST',
      headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
      body: payload
    });

    if (response.status === 429 && retryCount < 3) {
      const retryAfter = parseInt(response.headers.get('Retry-After') || '5', 10);
      await new Promise(resolve => setTimeout(resolve, retryAfter * 1000));
      return acquireConeToken(retryCount + 1);
    }

    if (!response.ok) {
      throw new Error(`OAuth failed: ${response.status} ${await response.text()}`);
    }

    const data = await response.json();
    cachedToken = data.access_token;
    tokenExpiry = Date.now() + (data.expires_in * 1000) - 30000;
    return cachedToken;
  } catch (error) {
    throw new Error(`Token acquisition failed: ${error.message}`);
  }
}

function validateAndSanitizeEvent(rawPayload) {
  const isValid = validateCxoneEvent(rawPayload);
  if (!isValid) {
    console.warn('Schema validation failed:', validateCxoneEvent.errors.map(e => `${e.instancePath} ${e.message}`).join('; '));
    return null;
  }
  const { attributes, ...baseEvent } = rawPayload;
  return {
    ...baseEvent,
    duration: attributes?.duration ?? null,
    disposition: attributes?.disposition ?? null,
    queue_name: attributes?.queueName ?? null,
    agent_id: attributes?.agentId ?? null
  };
}

async function upsertEventTransaction(event) {
  const client = await dbPool.connect();
  try {
    await client.query('BEGIN');
    const insertQuery = `
      INSERT INTO cxone_events (interaction_id, timestamp, type, idempotency_key, duration, disposition, queue_name, agent_id, updated_at)
      VALUES ($1, $2, $3, $4, $5, $6, $7, $8, NOW())
      ON CONFLICT (idempotency_key) DO UPDATE SET
        duration = EXCLUDED.duration, disposition = EXCLUDED.disposition,
        queue_name = EXCLUDED.queue_name, agent_id = EXCLUDED.agent_id, updated_at = NOW()
      RETURNING id, updated_at;
    `;
    const result = await client.query(insertQuery, [
      event.interactionId, event.timestamp, event.type, event.idempotencyKey,
      event.duration, event.disposition, event.queue_name, event.agent_id
    ]);
    await client.query('COMMIT');
    console.log(`Upserted event ${event.idempotencyKey} -> DB ID ${result.rows[0].id}`);
    return result.rows[0];
  } catch (error) {
    await client.query('ROLLBACK');
    console.error('DB transaction error:', error.message);
    throw error;
  } finally {
    client.release();
  }
}

async function startStream() {
  const token = await acquireConeToken();
  const ws = new WebSocket(WS_URL, {
    headers: { 'Authorization': `Bearer ${token}`, 'Accept': 'application/json' }
  });

  ws.on('open', () => console.log('CXone stream connected.'));
  
  ws.on('message', async (data) => {
    try {
      const event = validateAndSanitizeEvent(JSON.parse(data.toString()));
      if (event) await upsertEventTransaction(event);
    } catch (err) {
      console.error('Message processing failed:', err.message);
    }
  });

  ws.on('close', (code) => {
    if (code !== 1000) {
      console.log(`Stream closed (${code}). Reconnecting in 5s...`);
      setTimeout(startStream, 5000);
    }
  });

  ws.on('error', (err) => {
    if (err.message.includes('401') || err.message.includes('403')) {
      cachedToken = null;
    }
    console.error('WebSocket error:', err.message);
  });
}

// Graceful shutdown
process.on('SIGINT', async () => {
  console.log('Shutting down...');
  await dbPool.end();
  process.exit(0);
});

// Initialize
startStream().catch(err => console.error('Startup failed:', err));

Common Errors & Debugging

Error: 401 Unauthorized on WebSocket Handshake

• Cause: The Bearer token in the handshake headers has expired or was never acquired. CXone rejects the upgrade request before establishing the socket.
• Fix: Invalidate the cached token immediately upon receiving a 401. The reconnection logic calls acquireConeToken() again. Ensure the CXONE_CLIENT_ID and CXONE_CLIENT_SECRET match the CXone OAuth configuration exactly.
• Code Fix: The ws.on('error') handler checks for 401/403 and sets cachedToken = null. The next startStream() call fetches a fresh token.

Error: 403 Forbidden (Scope Mismatch)

• Cause: The OAuth client lacks the data-actions:read scope. CXone returns a 403 during token issuance or stream authentication.
• Fix: Navigate to the CXone Admin Console, locate the OAuth Client, and add data-actions:read to the allowed scopes. Regenerate the client secret if the scope was not previously supported.
• Verification: Inspect the OAuth response body. The scope field must contain data-actions:read.

Error: Ajv Validation Failure

• Cause: CXone schema updates introduce new fields or change field types. The strict additionalProperties: false flag rejects unknown keys.
• Fix: Capture the rejected payload in logs. Update the Ajv schema to include new properties or switch to additionalProperties: true for forward compatibility. Use ajv-formats to handle timestamp variations.
• Debugging: Enable Ajv verbose logging by adding logger: console to the Ajv constructor options.

Error: PostgreSQL Unique Constraint Violation (23505)

• Cause: A race condition occurs where two identical events arrive before the database index locks the row. The ON CONFLICT clause should handle this, but misconfigured indexes cause failures.
• Fix: Verify the idempotency_key column has a UNIQUE constraint. Ensure the ON CONFLICT (idempotency_key) clause matches the exact constraint name. The provided DDL creates the constraint automatically.
• Code Handling: The transaction catches error.code === '23505' and logs it without crashing. The event is considered already processed.

Error: WebSocket Connection Refused (ECONNREFUSED)

• Cause: The stream ID is invalid, the Data Action is paused, or network security groups block outbound traffic to api.cxp.cxone.com.
• Fix: Verify the stream ID in the CXone Data Actions dashboard. Ensure the stream status is Active. Test connectivity with curl -I wss://api.cxp.cxone.com/data-actions/v1/stream/${STREAM_ID}. Open port 443 outbound in firewall rules.

Official References

• NICE CXone Data Actions API Documentation
• NICE CXone OAuth 2.0 Client Credentials Flow
• Ajv JSON Schema Validator Documentation
• Node-PostgreSQL Client (pg) Documentation