Transcribing NICE CXone Agent Recordings via Recording API with Java

What You Will Build

• A Java service that submits asynchronous transcription jobs for CXone recordings, polls for completion with progress tracking, applies timestamp alignment and punctuation normalization, and emits webhook-ready payloads for external knowledge management systems.
• This tutorial uses the NICE CXone Recording and Transcription REST APIs.
• The implementation is written in Java 17 using java.net.http.HttpClient, jackson-databind, and micrometer-core for metrics.

Prerequisites

• OAuth 2.0 client credentials with scopes: recordings:read, transcriptions:write, transcriptions:read
• CXone API version: /api/v2
• Java 17+ runtime
• External dependencies:
  • com.fasterxml.jackson.core:jackson-databind:2.15.2
  • com.fasterxml.jackson.datatype:jackson-datatype-jsr310:2.15.2
  • io.micrometer:micrometer-core:1.11.0
  • org.slf4j:slf4j-api:2.0.9

Authentication Setup

CXone uses standard OAuth 2.0 client credentials flow. The following code fetches an access token, caches it, and handles expiration. The SDK equivalent is com.nice.cxp.sdk.client.ApiClient with setAccessToken().

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import io.micrometer.core.instrument.MeterRegistry;
import io.micrometer.core.instrument.simple.SimpleMeterRegistry;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.IOException;
import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.time.Instant;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.TimeUnit;

public class CxoneAuthService {
    private static final Logger log = LoggerFactory.getLogger(CxoneAuthService.class);
    private static final String TOKEN_URL = "https://api-us-1.cxone.com/api/v2/oauth/token";
    private final HttpClient httpClient;
    private final ObjectMapper mapper;
    private final MeterRegistry metrics;
    private final ConcurrentHashMap<String, TokenCache> tokenCache = new ConcurrentHashMap<>();

    public CxoneAuthService() {
        this.httpClient = HttpClient.newBuilder()
                .connectTimeout(Duration.ofSeconds(10))
                .followRedirects(HttpClient.Redirect.NEVER)
                .build();
        this.mapper = new ObjectMapper();
        this.metrics = new SimpleMeterRegistry();
    }

    public String getAccessToken(String clientId, String clientSecret) throws IOException, InterruptedException {
        TokenCache cached = tokenCache.get(clientId);
        if (cached != null && cached.isValid()) {
            return cached.token;
        }

        String body = String.format("grant_type=client_credentials&client_id=%s&client_secret=%s",
                java.net.URLEncoder.encode(clientId, java.nio.charset.StandardCharsets.UTF_8),
                java.net.URLEncoder.encode(clientSecret, java.nio.charset.StandardCharsets.UTF_8));

        HttpRequest request = HttpRequest.newBuilder()
                .uri(URI.create(TOKEN_URL))
                .header("Content-Type", "application/x-www-form-urlencoded")
                .POST(HttpRequest.BodyPublishers.ofString(body))
                .build();

        HttpResponse<String> response = httpClient.send(request, HttpResponse.BodyHandlers.ofString());

        if (response.statusCode() == 429) {
            long retryAfter = Long.parseLong(response.headers().firstValue("Retry-After").orElse("5"));
            log.warn("Rate limited on token request. Waiting {} seconds.", retryAfter);
            Thread.sleep(TimeUnit.SECONDS.toMillis(retryAfter));
            return getAccessToken(clientId, clientSecret);
        }

        if (response.statusCode() != 200) {
            throw new IOException("Token request failed with status " + response.statusCode() + ": " + response.body());
        }

        JsonNode json = mapper.readTree(response.body());
        String token = json.get("access_token").asText();
        long expiresIn = json.get("expires_in").asLong();

        tokenCache.put(clientId, new TokenCache(token, Instant.now().plusSeconds(expiresIn)));
        metrics.counter("cxone.oauth.token.requests").increment();
        return token;
    }

    private record TokenCache(String token, Instant expiresAt) {
        public boolean isValid() {
            return Instant.now().isBefore(expiresAt.minusSeconds(30));
        }
    }
}

Implementation

Step 1: Validate Audio Format Constraints and ASR Model Availability

CXone transcriptions fail silently or return 400 errors if the recording format or language code is unsupported. You must validate these parameters before submission. The SDK equivalent is com.nice.cxp.sdk.api.RecordingsApi.getRecordingById().

import java.util.Set;

public class CxoneValidationService {
    private static final Set<String> SUPPORTED_FORMATS = Set.of("audio/wav", "audio/mp3", "audio/ogg", "audio/webm");
    private static final Set<String> SUPPORTED_LANGUAGES = Set.of("en-US", "es-ES", "fr-FR", "de-DE", "pt-BR", "ja-JP");

    public void validateRecordingAndLanguage(String recordingId, String language, CxoneAuthService authService, String clientId, String clientSecret) throws Exception {
        String token = authService.getAccessToken(clientId, clientSecret);
        String recordingUrl = "https://api-us-1.cxone.com/api/v2/recordings/" + recordingId;

        HttpRequest request = HttpRequest.newBuilder()
                .uri(URI.create(recordingUrl))
                .header("Authorization", "Bearer " + token)
                .header("Accept", "application/json")
                .GET()
                .build();

        HttpResponse<String> response = HttpClient.newHttpClient().send(request, HttpResponse.BodyHandlers.ofString());

        if (response.statusCode() == 401) throw new SecurityException("Invalid or expired OAuth token");
        if (response.statusCode() == 403) throw new SecurityException("Missing recordings:read scope");
        if (response.statusCode() != 200) throw new IOException("Recording fetch failed: " + response.body());

        ObjectMapper mapper = new ObjectMapper();
        JsonNode recording = mapper.readTree(response.body());
        String format = recording.get("format").asText();

        if (!SUPPORTED_FORMATS.contains(format)) {
            throw new IllegalArgumentException("Unsupported audio format: " + format + ". Supported: " + SUPPORTED_FORMATS);
        }
        if (!SUPPORTED_LANGUAGES.contains(language)) {
            throw new IllegalArgumentException("Unsupported ASR language model: " + language + ". Supported: " + SUPPORTED_LANGUAGES);
        }

        log.info("Validation passed for recording {} with format {} and language {}", recordingId, format, language);
    }
}

Step 2: Construct and Submit Transcription Job Payload

The transcription endpoint accepts a JSON payload defining media references, language, diarization, and punctuation flags. The SDK equivalent is com.nice.cxp.sdk.api.TranscriptionsApi.postTranscriptions(). Required scope: transcriptions:write.

public class CxoneTranscriptionService {
    private static final Logger log = LoggerFactory.getLogger(CxoneTranscriptionService.class);
    private final HttpClient httpClient;
    private final ObjectMapper mapper;

    public CxoneTranscriptionService() {
        this.httpClient = HttpClient.newBuilder()
                .connectTimeout(Duration.ofSeconds(10))
                .build();
        this.mapper = new ObjectMapper();
        mapper.registerModule(new JavaTimeModule());
    }

    public String submitTranscriptionJob(String recordingId, String language, boolean diarization, CxoneAuthService authService, String clientId, String clientSecret) throws Exception {
        String token = authService.getAccessToken(clientId, clientSecret);
        String endpoint = "https://api-us-1.cxone.com/api/v2/recordings/transcriptions";

        Map<String, Object> payload = Map.of(
                "recordingId", recordingId,
                "language", language,
                "speakerDiarization", diarization,
                "punctuation", true,
                "timestamps", true
        );

        String jsonBody = mapper.writeValueAsString(payload);

        HttpRequest request = HttpRequest.newBuilder()
                .uri(URI.create(endpoint))
                .header("Authorization", "Bearer " + token)
                .header("Content-Type", "application/json")
                .header("Accept", "application/json")
                .POST(HttpRequest.BodyPublishers.ofString(jsonBody))
                .build();

        HttpResponse<String> response = httpClient.send(request, HttpResponse.BodyHandlers.ofString());

        if (response.statusCode() == 429) {
            long retryAfter = Long.parseLong(response.headers().firstValue("Retry-After").orElse("5"));
            log.warn("Rate limited on transcription submission. Waiting {} seconds.", retryAfter);
            Thread.sleep(TimeUnit.SECONDS.toMillis(retryAfter));
            return submitTranscriptionJob(recordingId, language, diarization, authService, clientId, clientSecret);
        }

        if (response.statusCode() == 400) {
            throw new IllegalArgumentException("Payload validation failed: " + response.body());
        }
        if (response.statusCode() == 401 || response.statusCode() == 403) {
            throw new SecurityException("Auth failure on transcription submission: " + response.statusCode());
        }

        JsonNode result = mapper.readTree(response.body());
        String transcriptionId = result.get("id").asText();
        log.info("Transcription job submitted successfully. ID: {}", transcriptionId);
        return transcriptionId;
    }
}

Step 3: Poll Asynchronous Jobs with Progress Tracking and Compute Monitoring

CXone processes transcriptions asynchronously. You must poll the job endpoint until completion. This step implements exponential backoff, progress tracking, and compute resource monitoring via processing duration. The SDK equivalent is com.nice.cxp.sdk.api.TranscriptionsApi.getTranscriptionById(). Required scope: transcriptions:read.

public record TranscriptionStatus(String id, String status, Instant startTime, Instant endTime, Double confidence) {}

public class CxonePollingService {
    private static final Logger log = LoggerFactory.getLogger(CxonePollingService.class);
    private final HttpClient httpClient;
    private final ObjectMapper mapper;
    private final MeterRegistry metrics;

    public CxonePollingService(MeterRegistry metrics) {
        this.httpClient = HttpClient.newHttpClient();
        this.mapper = new ObjectMapper();
        mapper.registerModule(new JavaTimeModule());
        this.metrics = metrics;
    }

    public TranscriptionStatus pollUntilComplete(String transcriptionId, CxoneAuthService authService, String clientId, String clientSecret) throws Exception {
        int maxAttempts = 60;
        int attempt = 0;
        long baseDelay = 5000;

        while (attempt < maxAttempts) {
            String token = authService.getAccessToken(clientId, clientSecret);
            String url = "https://api-us-1.cxone.com/api/v2/recordings/transcriptions/" + transcriptionId;

            HttpRequest request = HttpRequest.newBuilder()
                    .uri(URI.create(url))
                    .header("Authorization", "Bearer " + token)
                    .header("Accept", "application/json")
                    .GET()
                    .build();

            HttpResponse<String> response = httpClient.send(request, HttpResponse.BodyHandlers.ofString());

            if (response.statusCode() == 429) {
                long retryAfter = Long.parseLong(response.headers().firstValue("Retry-After").orElse("5"));
                log.warn("Rate limited during polling. Waiting {} seconds.", retryAfter);
                Thread.sleep(TimeUnit.SECONDS.toMillis(retryAfter));
                continue;
            }
            if (response.statusCode() != 200) {
                throw new IOException("Polling failed with status " + response.statusCode() + ": " + response.body());
            }

            JsonNode data = mapper.readTree(response.body());
            String status = data.get("status").asText();
            Instant startTime = data.has("startTime") ? Instant.parse(data.get("startTime").asText()) : null;
            Instant endTime = data.has("endTime") ? Instant.parse(data.get("endTime").asText()) : null;
            double confidence = data.has("confidence") ? data.get("confidence").asDouble() : 0.0;

            log.info("Transcription {} status: {} (Attempt {}/{})", transcriptionId, status, attempt + 1, maxAttempts);

            if ("completed".equalsIgnoreCase(status)) {
                if (startTime != null && endTime != null) {
                    long computeMs = java.time.Duration.between(startTime, endTime).toMillis();
                    metrics.timer("cxone.transcription.compute.time").record(computeMs, TimeUnit.MILLISECONDS);
                }
                return new TranscriptionStatus(transcriptionId, status, startTime, endTime, confidence);
            }

            if ("failed".equalsIgnoreCase(status)) {
                String errorReason = data.has("reason") ? data.get("reason").asText() : "Unknown";
                throw new RuntimeException("Transcription failed: " + errorReason);
            }

            attempt++;
            long delay = Math.min(baseDelay * (1L << (attempt / 3)), 30000);
            Thread.sleep(delay);
        }

        throw new TimeoutException("Transcription did not complete within polling window");
    }
}

Step 4: Post-Processing, Webhook Synchronization, and Audit Logging

After completion, fetch the full transcript, align timestamps, normalize punctuation, generate a readable summary, and emit a webhook payload. This step also records latency, accuracy metrics, and compliance audit logs.

import java.util.List;
import java.util.stream.Collectors;

public class CxonePostProcessor {
    private static final Logger log = LoggerFactory.getLogger(CxonePostProcessor.class);
    private final HttpClient httpClient;
    private final ObjectMapper mapper;
    private final MeterRegistry metrics;

    public CxonePostProcessor(MeterRegistry metrics) {
        this.httpClient = HttpClient.newHttpClient();
        this.mapper = new ObjectMapper();
        mapper.registerModule(new JavaTimeModule());
        this.metrics = metrics;
    }

    public String processAndEmitWebhook(String transcriptionId, String webhookUrl, CxoneAuthService authService, String clientId, String clientSecret) throws Exception {
        String token = authService.getAccessToken(clientId, clientSecret);
        String url = "https://api-us-1.cxone.com/api/v2/recordings/transcriptions/" + transcriptionId;

        HttpRequest request = HttpRequest.newBuilder()
                .uri(URI.create(url))
                .header("Authorization", "Bearer " + token)
                .header("Accept", "application/json")
                .GET()
                .build();

        HttpResponse<String> response = httpClient.send(request, HttpResponse.BodyHandlers.ofString());
        if (response.statusCode() != 200) throw new IOException("Failed to fetch transcript: " + response.body());

        JsonNode transcript = mapper.readTree(response.body());
        JsonNode sentences = transcript.get("sentences");
        String language = transcript.get("language").asText();
        String recordingId = transcript.get("recordingId").asText();

        // Timestamp alignment and punctuation normalization
        List<Map<String, Object>> alignedSentences = sentences.toStream()
                .map(node -> {
                    Map<String, Object> sentence = new LinkedHashMap<>();
                    sentence.put("speaker", node.get("speaker").asText());
                    String text = node.get("text").asText();
                    // Ensure punctuation exists
                    if (!text.matches(".*[.!?]$")) {
                        text = text + ".";
                    }
                    sentence.put("text", text);
                    sentence.put("startTime", node.get("startTime").asText());
                    sentence.put("endTime", node.get("endTime").asText());
                    sentence.put("confidence", node.get("confidence").asDouble());
                    return sentence;
                })
                .collect(Collectors.toList());

        // Generate readable summary
        String summary = alignedSentences.stream()
                .map(s -> String.format("[%s] %s", s.get("speaker"), s.get("text")))
                .collect(Collectors.joining("\n"));

        // Track accuracy and latency metrics
        double avgConfidence = sentences.toStream().mapToDouble(n -> n.get("confidence").asDouble()).average().orElse(0.0);
        metrics.gauge("cxone.transcription.accuracy.avg", avgConfidence);
        metrics.counter("cxone.transcription.jobs.completed").increment();

        // Audit log
        String auditPayload = String.format(
                "{\"event\":\"transcription.completed\",\"recordingId\":\"%s\",\"transcriptionId\":\"%s\",\"language\":\"%s\",\"sentenceCount\":%d,\"avgConfidence\":%.4f,\"timestamp\":\"%s\"}",
                recordingId, transcriptionId, language, sentences.size(), avgConfidence, Instant.now().toString()
        );
        log.info("AUDIT: {}", auditPayload);

        // Webhook synchronization
        String webhookBody = mapper.writeValueAsString(Map.of(
                "type", "transcription.completed",
                "recordingId", recordingId,
                "transcriptionId", transcriptionId,
                "summary", summary,
                "sentences", alignedSentences,
                "metrics", Map.of("avgConfidence", avgConfidence)
        ));

        HttpRequest webhookRequest = HttpRequest.newBuilder()
                .uri(URI.create(webhookUrl))
                .header("Content-Type", "application/json")
                .header("X-Transcription-Id", transcriptionId)
                .POST(HttpRequest.BodyPublishers.ofString(webhookBody))
                .build();

        HttpResponse<String> webhookResponse = httpClient.send(webhookRequest, HttpResponse.BodyHandlers.ofString());
        log.info("Webhook dispatched with status {}: {}", webhookResponse.statusCode(), webhookResponse.body());

        return summary;
    }
}

Complete Working Example

The following class orchestrates validation, submission, polling, and post-processing into a single executable workflow. Replace the placeholder credentials and endpoints before execution.

import java.time.Duration;
import java.util.Map;

public class RecordingTranscriber {
    private static final Logger log = LoggerFactory.getLogger(RecordingTranscriber.class);

    public static void main(String[] args) {
        String clientId = System.getenv("CXONE_CLIENT_ID");
        String clientSecret = System.getenv("CXONE_CLIENT_SECRET");
        String recordingId = System.getenv("CXONE_RECORDING_ID");
        String targetLanguage = System.getenv("CXONE_LANGUAGE");
        String webhookUrl = System.getenv("KM_WEBHOOK_URL");

        if (recordingId == null || recordingId.isEmpty()) {
            log.error("CXONE_RECORDING_ID environment variable is required");
            return;
        }

        CxoneAuthService authService = new CxoneAuthService();
        CxoneValidationService validator = new CxoneValidationService();
        CxoneTranscriptionService transcriber = new CxoneTranscriptionService();
        MeterRegistry metrics = new SimpleMeterRegistry();
        CxonePollingService poller = new CxonePollingService(metrics);
        CxonePostProcessor processor = new CxonePostProcessor(metrics);

        try {
            log.info("Starting transcription workflow for recording {}", recordingId);

            // Step 1: Validate
            validator.validateRecordingAndLanguage(recordingId, targetLanguage != null ? targetLanguage : "en-US", authService, clientId, clientSecret);

            // Step 2: Submit
            String transcriptionId = transcriber.submitTranscriptionJob(
                    recordingId,
                    targetLanguage != null ? targetLanguage : "en-US",
                    true,
                    authService, clientId, clientSecret
            );

            // Step 3: Poll
            TranscriptionStatus status = poller.pollUntilComplete(transcriptionId, authService, clientId, clientSecret);
            log.info("Transcription completed. Status: {}, Confidence: {}", status.status(), status.confidence());

            // Step 4: Post-process and Webhook
            String summary = processor.processAndEmitWebhook(transcriptionId, webhookUrl, authService, clientId, clientSecret);
            log.info("Final Summary:\n{}", summary);

        } catch (Exception e) {
            log.error("Transcription workflow failed", e);
            metrics.counter("cxone.transcription.jobs.failed").increment();
        }
    }
}

Common Errors & Debugging

Error: 400 Bad Request

• What causes it: The recording format is unsupported, the language code is invalid, or the payload structure violates the CXone schema.
• How to fix it: Verify the recording format matches audio/wav, audio/mp3, audio/ogg, or audio/webm. Ensure the language code matches a supported ASR model (en-US, es-ES, fr-FR, de-DE, pt-BR, ja-JP). Validate JSON structure before submission.
• Code showing the fix: The CxoneValidationService enforces format and language constraints before the POST request executes.

Error: 401 Unauthorized or 403 Forbidden

• What causes it: The OAuth token is expired, malformed, or lacks the required scopes (recordings:read, transcriptions:write, transcriptions:read).
• How to fix it: Refresh the token using CxoneAuthService.getAccessToken(). Verify the CXone client credentials grant the exact scopes required for the operation.
• Code showing the fix: The getAccessToken() method checks expiration and automatically re-fetches tokens. The polling and submission methods throw explicit SecurityException on auth failures.

Error: 429 Too Many Requests

• What causes it: CXone enforces rate limits per client ID and per endpoint. Batch processing without backoff triggers cascading 429 responses.
• How to fix it: Implement exponential backoff and respect the Retry-After header. Never retry immediately.
• Code showing the fix: Both submitTranscriptionJob() and pollUntilComplete() parse the Retry-After header and sleep before retrying. The polling loop uses dynamic backoff (baseDelay * (1L << (attempt / 3))).

Error: 503 Service Unavailable or ASR Model Timeout

• What causes it: The ASR compute cluster is saturated or the specific language model is temporarily offline.
• How to fix it: Retry the job after a longer delay. Monitor cxone.transcription.compute.time metrics to detect cluster degradation.
• Code showing the fix: The CxonePollingService tracks compute duration via Micrometer. If processing exceeds expected thresholds, you can alert on cxone.transcription.compute.time percentiles.

Official References

• CXone Transcription API Documentation
• CXone OAuth 2.0 Client Credentials Flow
• CXone Java SDK Reference
• CXone Webhooks and Event Routing