Purging Genesys Cloud Outbound DNC Lists via API with Node.js

What You Will Build

A Node.js module that validates, hashes, and atomically purges phone numbers from Genesys Cloud DNC lists while enforcing batch limits, legal-hold checks, partial-match safeguards, and external compliance webhooks. It uses the @genesyscloud/purecloud-platform-client-v2 SDK and exposes a production-ready DncNumberPurger class. The tutorial covers JavaScript/Node.js.

Prerequisites

• OAuth Client Credentials grant flow with client_id and client_secret
• Required OAuth scope: dnc:write
• Genesys Cloud API version: v2
• Runtime: Node.js 18 or higher
• Dependencies: @genesyscloud/purecloud-platform-client-v2, axios, dotenv, crypto (built-in)

Authentication Setup

Genesys Cloud uses OAuth 2.0 client credentials for server-to-server integrations. The SDK handles token caching and automatic refresh, but you must initialize it with your environment URL and credentials.

import dotenv from 'dotenv';
dotenv.config();

import { PureCloudPlatformClientV2 } from '@genesyscloud/purecloud-platform-client-v2';

const platformClient = new PureCloudPlatformClientV2();
platformClient.setEnvironment(process.env.GENESYS_ENV || 'mypurecloud.com');

// Configure client credentials authentication
platformClient.loginClientCredentials(
  process.env.GENESYS_CLIENT_ID,
  process.env.GENESYS_CLIENT_SECRET,
  ['dnc:write']
);

// Verify authentication before proceeding
platformClient.loginClientCredentials().then(() => {
  console.log('OAuth token acquired. Scope: dnc:write');
}).catch((err) => {
  console.error('Authentication failed:', err.message);
  process.exit(1);
});

The SDK stores the access token in memory and automatically requests a new token when expiration approaches. You do not need to implement manual token rotation unless you are caching tokens across multiple processes.

Implementation

Step 1: Validation Pipeline and Batch Chunking

The Genesys Cloud DNC purge endpoint enforces a maximum batch size. Requests exceeding the limit return a 400 Bad Request. You must chunk the number-matrix and validate each entry against E.164 format, partial-match safeguards, and legal-hold constraints before submission.

import crypto from 'crypto';
import axios from 'axios';

const MAX_BATCH_SIZE = 500;
const E164_REGEX = /^\+?[1-9]\d{1,14}$/;

/**
 * Validates phone numbers against compliance constraints
 */
function validateNumberMatrix(numbers, legalHoldList = [], protectedPrefixes = []) {
  const valid = [];
  const auditLog = [];

  for (const num of numbers) {
    const normalized = num.replace(/\D/g, '');
    const formatted = `+${normalized}`;

    // Format verification
    if (!E164_REGEX.test(formatted)) {
      auditLog.push({ number: num, status: 'rejected', reason: 'invalid_e164_format' });
      continue;
    }

    // Legal-hold verification pipeline
    if (legalHoldList.includes(formatted)) {
      auditLog.push({ number: num, status: 'rejected', reason: 'legal_hold_active' });
      continue;
    }

    // Partial-match checking to prevent accidental removal of similar ranges
    const isPartialMatch = protectedPrefixes.some(prefix => formatted.startsWith(prefix));
    if (isPartialMatch) {
      auditLog.push({ number: num, status: 'rejected', reason: 'partial_match_protected' });
      continue;
    }

    valid.push(formatted);
    auditLog.push({ number: num, status: 'accepted', reason: 'passed_validation' });
  }

  return { valid, auditLog };
}

/**
 * Chunks array to respect maximum-batch-size limits
 */
function chunkArray(array, size) {
  const chunks = [];
  for (let i = 0; i < array.length; i += size) {
    chunks.push(array.slice(i, i + size));
  }
  return chunks;
}

Step 2: Hash-Matching Calculation and Atomic HTTP DELETE/POST Cycle

Genesys Cloud treats the purge operation as an atomic transaction. The official endpoint uses POST /api/v2/outbound/dnc/numbers/purge. You must compute a SHA-256 hash of the batch for audit-trail evaluation and format verification. The following code demonstrates the exact HTTP request/response cycle alongside the SDK call.

/**
 * Computes batch hash for audit trail evaluation
 */
function computeBatchHash(batch) {
  const sorted = [...batch].sort().join(',');
  return crypto.createHash('sha256').update(sorted).digest('hex');
}

/**
 * Executes atomic purge with retry logic for 429 rate limits
 */
async function executeAtomicPurge(platformClient, dncListId, batch, externalWebhookUrl) {
  const startTimestamp = Date.now();
  const batchHash = computeBatchHash(batch);
  
  const payload = {
    numbers: batch,
    dncListId: dncListId || undefined
  };

  // Raw HTTP cycle for transparency and debugging
  const token = await platformClient.getAccessToken();
  const env = platformClient.getEnvironment();
  const baseUrl = `https://${env}.mypurecloud.com`;
  const endpoint = '/api/v2/outbound/dnc/numbers/purge';

  const headers = {
    'Authorization': `Bearer ${token}`,
    'Content-Type': 'application/json',
    'X-Genesys-Client-Id': 'node-dnc-purger-v1'
  };

  const response = await axios.post(`${baseUrl}${endpoint}`, payload, { headers });

  // Record latency and success metrics
  const latencyMs = Date.now() - startTimestamp;
  const successCount = response.data.successCount || batch.length;
  const skippedCount = response.data.skippedCount || 0;

  // Automatic archive trigger for safe remove iteration
  const archiveRecord = {
    dncListId,
    batchHash,
    numbers: batch,
    successCount,
    skippedCount,
    latencyMs,
    timestamp: new Date().toISOString(),
    status: successCount > 0 ? 'archived_and_purged' : 'purge_failed'
  };

  // Synchronize purging events with external compliance via webhook
  if (externalWebhookUrl) {
    await axios.post(externalWebhookUrl, archiveRecord, {
      headers: { 'Content-Type': 'application/json' }
    }).catch((webhookErr) => {
      console.warn('External compliance webhook failed:', webhookErr.message);
    });
  }

  return archiveRecord;
}

Step 3: Processing Results and Metrics Aggregation

You must track purging latency, remove success rates, and generate structured audit logs for DNC governance. The following function aggregates results across all chunks and exposes a final governance report.

function aggregatePurgeResults(purgeRecords) {
  const totalNumbers = purgeRecords.reduce((sum, r) => sum + r.successCount + r.skippedCount, 0);
  const totalSuccess = purgeRecords.reduce((sum, r) => sum + r.successCount, 0);
  const totalSkipped = purgeRecords.reduce((sum, r) => sum + r.skippedCount, 0);
  const avgLatency = purgeRecords.reduce((sum, r) => sum + r.latencyMs, 0) / purgeRecords.length;

  return {
    totalNumbers,
    totalSuccess,
    totalSkipped,
    successRate: totalNumbers > 0 ? (totalSuccess / totalNumbers) * 100 : 0,
    averageLatencyMs: avgLatency.toFixed(2),
    governanceLog: purgeRecords
  };
}

Complete Working Example

The following module combines authentication, validation, chunking, atomic execution, and metrics aggregation into a single exportable class. Replace the environment variables with your credentials.

import dotenv from 'dotenv';
dotenv.config();

import { PureCloudPlatformClientV2 } from '@genesyscloud/purecloud-platform-client-v2';
import axios from 'axios';
import crypto from 'crypto';

const MAX_BATCH_SIZE = 500;
const E164_REGEX = /^\+?[1-9]\d{1,14}$/;

export class DncNumberPurger {
  constructor(environment, clientId, clientSecret, externalWebhookUrl) {
    this.platformClient = new PureCloudPlatformClientV2();
    this.platformClient.setEnvironment(environment);
    this.clientId = clientId;
    this.clientSecret = clientSecret;
    this.externalWebhookUrl = externalWebhookUrl;
    this.metrics = { totalSuccess: 0, totalSkipped: 0, totalLatency: 0, chunkCount: 0 };
  }

  async initialize() {
    await this.platformClient.loginClientCredentials(
      this.clientId,
      this.clientSecret,
      ['dnc:write']
    );
    console.log('DncNumberPurger initialized with dnc:write scope.');
  }

  validateNumberMatrix(numbers, legalHoldList = [], protectedPrefixes = []) {
    const valid = [];
    const auditLog = [];

    for (const num of numbers) {
      const normalized = num.replace(/\D/g, '');
      const formatted = `+${normalized}`;

      if (!E164_REGEX.test(formatted)) {
        auditLog.push({ number: num, status: 'rejected', reason: 'invalid_e164_format' });
        continue;
      }
      if (legalHoldList.includes(formatted)) {
        auditLog.push({ number: num, status: 'rejected', reason: 'legal_hold_active' });
        continue;
      }
      const isPartialMatch = protectedPrefixes.some(prefix => formatted.startsWith(prefix));
      if (isPartialMatch) {
        auditLog.push({ number: num, status: 'rejected', reason: 'partial_match_protected' });
        continue;
      }

      valid.push(formatted);
      auditLog.push({ number: num, status: 'accepted', reason: 'passed_validation' });
    }

    return { valid, auditLog };
  }

  async executePurge(dncListId, numbers, legalHoldList = [], protectedPrefixes = []) {
    await this.initialize();

    const { valid, auditLog } = this.validateNumberMatrix(numbers, legalHoldList, protectedPrefixes);
    console.log(`Validation complete. Accepted: ${valid.length}, Rejected: ${auditLog.filter(a => a.status === 'rejected').length}`);

    if (valid.length === 0) {
      return { auditLog, metrics: this.metrics };
    }

    const chunks = this.chunkArray(valid, MAX_BATCH_SIZE);
    const purgeRecords = [];

    for (const chunk of chunks) {
      const startTimestamp = Date.now();
      const batchHash = this.computeBatchHash(chunk);

      const payload = {
        numbers: chunk,
        dncListId: dncListId || undefined
      };

      const token = await this.platformClient.getAccessToken();
      const env = this.platformClient.getEnvironment();
      const baseUrl = `https://${env}.mypurecloud.com`;
      const endpoint = '/api/v2/outbound/dnc/numbers/purge';

      const headers = {
        'Authorization': `Bearer ${token}`,
        'Content-Type': 'application/json',
        'X-Genesys-Client-Id': 'node-dnc-purger-v1'
      };

      try {
        const response = await axios.post(`${baseUrl}${endpoint}`, payload, { headers });
        const latencyMs = Date.now() - startTimestamp;
        const successCount = response.data.successCount || chunk.length;
        const skippedCount = response.data.skippedCount || 0;

        this.metrics.totalSuccess += successCount;
        this.metrics.totalSkipped += skippedCount;
        this.metrics.totalLatency += latencyMs;
        this.metrics.chunkCount += 1;

        const archiveRecord = {
          dncListId,
          batchHash,
          numbers: chunk,
          successCount,
          skippedCount,
          latencyMs,
          timestamp: new Date().toISOString(),
          status: successCount > 0 ? 'archived_and_purged' : 'purge_failed'
        };

        purgeRecords.push(archiveRecord);

        if (this.externalWebhookUrl) {
          await axios.post(this.externalWebhookUrl, archiveRecord, {
            headers: { 'Content-Type': 'application/json' }
          }).catch((webhookErr) => {
            console.warn('External compliance webhook failed:', webhookErr.message);
          });
        }
      } catch (httpError) {
        if (httpError.response?.status === 429) {
          const retryAfter = httpError.response.headers['retry-after'] || 5;
          console.warn(`Rate limited. Retrying after ${retryAfter}s...`);
          await new Promise(resolve => setTimeout(resolve, retryAfter * 1000));
          // Re-queue chunk for retry
          chunks.push(chunk);
          continue;
        }
        throw httpError;
      }
    }

    const finalMetrics = {
      ...this.metrics,
      successRate: (this.metrics.totalSuccess / (this.metrics.totalSuccess + this.metrics.totalSkipped)) * 100,
      averageLatencyMs: this.metrics.chunkCount > 0 ? (this.metrics.totalLatency / this.metrics.chunkCount).toFixed(2) : 0
    };

    return { auditLog, purgeRecords, metrics: finalMetrics };
  }

  computeBatchHash(batch) {
    const sorted = [...batch].sort().join(',');
    return crypto.createHash('sha256').update(sorted).digest('hex');
  }

  chunkArray(array, size) {
    const chunks = [];
    for (let i = 0; i < array.length; i += size) {
      chunks.push(array.slice(i, i + size));
    }
    return chunks;
  }
}

// Usage Example
if (process.argv[1] === import.meta.url) {
  const purger = new DncNumberPurger(
    process.env.GENESYS_ENV,
    process.env.GENESYS_CLIENT_ID,
    process.env.GENESYS_CLIENT_SECRET,
    process.env.EXTERNAL_COMPLIANCE_WEBHOOK
  );

  const testNumbers = ['+15551234567', '+15559876543', 'invalid', '+15550000000'];
  const legalHolds = ['+15559876543'];
  const protectedPrefixes = ['+155500'];

  purger.executePurge(process.env.DNC_LIST_ID, testNumbers, legalHolds, protectedPrefixes)
    .then((result) => {
      console.log('Purge Complete:', JSON.stringify(result, null, 2));
    })
    .catch((err) => {
      console.error('Fatal purge error:', err.message);
    });
}

Common Errors & Debugging

Error: 400 Bad Request

• What causes it: The payload exceeds the maximum batch size, contains malformed E.164 numbers, or references a non-existent dncListId.
• How to fix it: Verify chunking logic matches MAX_BATCH_SIZE. Run the validation pipeline before submission. Ensure dncListId matches an active campaign list.
• Code showing the fix: The validateNumberMatrix and chunkArray methods enforce format compliance and size limits before the HTTP call.

Error: 401 Unauthorized or 403 Forbidden

• What causes it: Missing dnc:write scope, expired token, or invalid client credentials.
• How to fix it: Regenerate OAuth credentials in the Genesys Cloud admin console. Confirm the scope array includes dnc:write. The SDK automatically refreshes tokens, but network restrictions may block the token endpoint.
• Code showing the fix: platformClient.loginClientCredentials(clientId, clientSecret, ['dnc:write']) explicitly requests the required scope.

Error: 429 Too Many Requests

• What causes it: Exceeding Genesys Cloud rate limits for DNC operations. Bulk purges trigger cascading limits across outbound microservices.
• How to fix it: Implement exponential backoff or respect the Retry-After header. The complete example catches 429 status codes and delays the next chunk.
• Code showing the fix: The try/catch block checks httpError.response?.status === 429, extracts retry-after, and re-queues the chunk.

Error: 409 Conflict

• What causes it: Attempting to purge numbers flagged under legal hold or partial-match protection.
• How to fix it: Review the auditLog output. Numbers rejected with legal_hold_active or partial_match_protected must be removed from the input matrix before resubmission.
• Code showing the fix: The validation pipeline explicitly checks legalHoldList and protectedPrefixes and returns rejected entries in the audit log.

Official References

• Genesys Cloud DNC API Documentation
• Outbound DNC Purge Endpoint
• PureCloud Platform Client V2 SDK Reference
• OAuth 2.0 Client Credentials Flow