Transcoding Genesys Cloud Media Streams with Java via the Media API

What You Will Build

This tutorial builds a Java service that queries Genesys Cloud media assets, constructs transcoding payloads with stream-ref, codec-matrix, and convert directives, validates against CPU load constraints and maximum output quality limits, executes atomic HTTP PUT operations with automatic process triggers, synchronizes transcoding events via webhooks, tracks latency and success rates, and generates audit logs for media governance. It uses the official Genesys Cloud Java SDK for asset retrieval and OkHttp for external media server communication. Java.

Prerequisites

• OAuth 2.0 Client Credentials grant type with scopes: media:read, recordings:read, media:write
• Genesys Cloud Java SDK v23.3.0 or later
• Java 17 or later
• Maven dependencies: com.mypurecloud.api:genesyscloud-java-sdk, com.squareup.okhttp3:okhttp, com.fasterxml.jackson.core:jackson-databind, org.slf4j:slf4j-api
• Access to an external media processing endpoint or hybrid cloud media server that accepts transcoding directives

Authentication Setup

Genesys Cloud requires OAuth 2.0 client credentials authentication. The following code obtains an access token and caches it for reuse. The token expires after one hour and must be refreshed before expiration.

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import okhttp3.*;
import java.io.IOException;
import java.util.concurrent.TimeUnit;

public class GenesysAuthManager {
    private final OkHttpClient httpClient;
    private final ObjectMapper mapper;
    private final String clientId;
    private final String clientSecret;
    private final String baseUrl = "https://api.mypurecloud.com";
    private volatile String cachedToken;
    private volatile long tokenExpiryEpoch;

    public GenesysAuthManager(String clientId, String clientSecret) {
        this.clientId = clientId;
        this.clientSecret = clientSecret;
        this.httpClient = new OkHttpClient.Builder()
                .connectTimeout(10, TimeUnit.SECONDS)
                .readTimeout(10, TimeUnit.SECONDS)
                .build();
        this.mapper = new ObjectMapper();
        this.tokenExpiryEpoch = 0;
    }

    public String getAccessToken() throws IOException {
        if (cachedToken != null && System.currentTimeMillis() < tokenExpiryEpoch - 60_000) {
            return cachedToken;
        }
        return refreshToken();
    }

    private String refreshToken() throws IOException {
        String basicAuth = Credentials.basic(clientId, clientSecret);
        RequestBody formBody = new FormBody.Builder()
                .add("grant_type", "client_credentials")
                .build();

        Request request = new Request.Builder()
                .url(baseUrl + "/oauth/token")
                .header("Authorization", basicAuth)
                .post(formBody)
                .build();

        try (Response response = httpClient.newCall(request).execute()) {
            if (!response.isSuccessful()) {
                throw new IOException("OAuth token request failed: " + response.code());
            }
            JsonNode json = mapper.readTree(response.body().string());
            cachedToken = json.get("access_token").asText();
            int expiresIn = json.get("expires_in").asInt();
            tokenExpiryEpoch = System.currentTimeMillis() + (expiresIn * 1000L);
            return cachedToken;
        }
    }
}

Implementation

Step 1: Query Media Assets and Initialize SDK

The Genesys Cloud Java SDK handles SDK initialization and pagination. You must configure the platform client with your OAuth token and region. The following code queries recordings that require transcoding.

import com.mypurecloud.api.v2.api.RecordingApi;
import com.mypurecloud.api.v2.client.Configuration;
import com.mypurecloud.api.v2.model.RecordingSearchResponse;
import com.mypurecloud.api.v2.model.RecordingSearchQuery;
import java.util.Collections;

public class MediaAssetFetcher {
    private final RecordingApi recordingApi;

    public MediaAssetFetcher(String accessToken, String region) {
        Configuration config = Configuration.getDefaultConfiguration();
        config.setHost(region + ".mypurecloud.com");
        config.setAccessToken(accessToken);
        this.recordingApi = new RecordingApi(config);
    }

    public RecordingSearchResponse fetchPendingRecordings() throws Exception {
        RecordingSearchQuery query = new RecordingSearchQuery()
                .query("status:ready")
                .pageSize(25)
                .page(1);
        
        return recordingApi.postMediaRecordingsSearch(query, Collections.emptyList(), null, null);
    }
}

Step 2: Construct Transcoding Payload and Validate Constraints

Transcoding payloads require explicit stream references, codec matrices, and convert directives. You must validate bitrate calculations, frame rate evaluation, and CPU load constraints before submission. The following code builds the payload and enforces quality limits.

import com.fasterxml.jackson.databind.ObjectMapper;
import java.util.Map;

public class TranscodePayloadBuilder {
    private final ObjectMapper mapper = new ObjectMapper();

    public record TranscodePayload(
            String streamRef,
            Map<String, Object> codecMatrix,
            String convert,
            int targetBitrateKbps,
            double targetFrameRate,
            int maxCpuLoadPercent
    ) {}

    public String buildPayload(String recordingId, String streamUrl, int targetBitrate, double frameRate) {
        validateConstraints(targetBitrate, frameRate);

        TranscodePayload payload = new TranscodePayload(
                streamUrl,
                Map.of(
                        "video", Map.of("codec", "h264", "profile", "main"),
                        "audio", Map.of("codec", "aac", "sampleRate", 48000, "channels", 2)
                ),
                "convert",
                targetBitrate,
                frameRate,
                85
        );

        try {
            return mapper.writeValueAsString(payload);
        } catch (Exception e) {
            throw new RuntimeException("Payload serialization failed", e);
        }
    }

    private void validateConstraints(int bitrateKbps, double frameRate) {
        if (bitrateKbps < 128 || bitrateKbps > 4096) {
            throw new IllegalArgumentException("Bitrate must be between 128 and 4096 kbps to prevent buffer overflow");
        }
        if (frameRate < 24.0 || frameRate > 60.0) {
            throw new IllegalArgumentException("Frame rate must be between 24.0 and 60.0 fps");
        }
        if (bitrateKbps > 2048 && frameRate > 30.0) {
            throw new IllegalArgumentException("High bitrate and high frame rate combination exceeds CPU load constraints");
        }
    }
}

Step 3: Execute Atomic HTTP PUT with Retry and Format Verification

The transcoding directive is submitted via an atomic HTTP PUT operation. The implementation includes exponential backoff for 429 rate limits, automatic process triggers for safe convert iteration, and format verification on response.

import okhttp3.*;
import java.io.IOException;
import java.util.concurrent.TimeUnit;

public class TranscodeExecutor {
    private final OkHttpClient httpClient;
    private final String mediaServerUrl;

    public TranscodeExecutor(String mediaServerUrl) {
        this.mediaServerUrl = mediaServerUrl;
        this.httpClient = new OkHttpClient.Builder()
                .connectTimeout(15, TimeUnit.SECONDS)
                .readTimeout(30, TimeUnit.SECONDS)
                .build();
    }

    public String executeTranscode(String accessToken, String payloadJson) throws IOException {
        RequestBody body = RequestBody.create(payloadJson, MediaType.parse("application/json"));
        Request request = new Request.Builder()
                .url(mediaServerUrl + "/api/v1/transcode/submit")
                .header("Authorization", "Bearer " + accessToken)
                .header("Content-Type", "application/json")
                .put(body)
                .build();

        int maxRetries = 3;
        long backoffMs = 1000;

        for (int attempt = 1; attempt <= maxRetries; attempt++) {
            try (Response response = httpClient.newCall(request).execute()) {
                if (response.code() == 429) {
                    if (attempt < maxRetries) {
                        Thread.sleep(backoffMs);
                        backoffMs *= 2;
                        continue;
                    }
                    throw new IOException("Rate limit exceeded after " + maxRetries + " retries");
                }
                if (response.isSuccessful()) {
                    String responseBody = response.body().string();
                    verifyTranscodeResponse(responseBody);
                    return responseBody;
                }
                throw new IOException("Transcode submission failed: " + response.code() + " " + response.body().string());
            } catch (InterruptedException e) {
                Thread.currentThread().interrupt();
                throw new IOException("Retry interrupted", e);
            }
        }
        throw new IOException("Unexpected retry loop termination");
    }

    private void verifyTranscodeResponse(String json) throws IOException {
        com.fasterxml.jackson.databind.ObjectMapper mapper = new com.fasterxml.jackson.databind.ObjectMapper();
        var node = mapper.readTree(json);
        if (node.path("status").asText().equals("queued") || node.path("status").asText().equals("processing")) {
            return;
        }
        throw new IOException("Invalid transcode response format");
    }
}

Step 4: Webhook Synchronization, Latency Tracking, and Audit Logging

Transcoding events must synchronize with external media servers via webhooks. The following code tracks latency, records success rates, and generates immutable audit logs for media governance.

import java.time.Instant;
import java.util.concurrent.ConcurrentHashMap;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class TranscodeGovernanceManager {
    private static final Logger logger = LoggerFactory.getLogger(TranscodeGovernanceManager.class);
    private final ConcurrentHashMap<String, Long> latencyTracker = new ConcurrentHashMap<>();
    private final ConcurrentHashMap<String, Integer> successCounter = new ConcurrentHashMap<>();
    private final ConcurrentHashMap<String, Integer> failureCounter = new ConcurrentHashMap<>();

    public void recordTranscodeEvent(String recordingId, String streamRef, boolean success, long durationMs) {
        latencyTracker.put(recordingId, durationMs);
        if (success) {
            successCounter.merge(recordingId, 1, Integer::sum);
        } else {
            failureCounter.merge(recordingId, 1, Integer::sum);
        }

        String auditLog = String.format(
                "AUDIT|%s|RECORDING:%s|STREAM:%s|STATUS:%s|LATENCY:%dms|TIMESTAMP:%s",
                Instant.now().toString(),
                recordingId,
                streamRef,
                success ? "SUCCESS" : "FAILED",
                durationMs,
                Instant.now().toString()
        );
        logger.info(auditLog);
        triggerWebhook(recordingId, success, durationMs);
    }

    private void triggerWebhook(String recordingId, boolean success, long durationMs) {
        // Webhook payload construction
        String payload = String.format(
                "{\"recordingId\":\"%s\",\"status\":\"%s\",\"latencyMs\":%d,\"timestamp\":\"%s\"}",
                recordingId, success ? "transcoded" : "transcode_failed", durationMs, Instant.now().toString()
        );
        
        // In production, enqueue this payload to an external webhook dispatcher
        logger.info("Webhook queued for recording {}: {}", recordingId, payload);
    }

    public double getSuccessRate(String recordingId) {
        int successes = successCounter.getOrDefault(recordingId, 0);
        int failures = failureCounter.getOrDefault(recordingId, 0);
        int total = successes + failures;
        return total == 0 ? 0.0 : (double) successes / total;
    }
}

Complete Working Example

The following class combines authentication, asset retrieval, payload construction, execution, and governance into a single runnable module. Replace placeholder credentials and endpoints with your environment values.

import com.mypurecloud.api.v2.model.RecordingSearchResponse;
import com.mypurecloud.api.v2.model.RecordingReference;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.time.Instant;
import java.util.List;

public class StreamTranscoderService {
    private static final Logger logger = LoggerFactory.getLogger(StreamTranscoderService.class);

    private final GenesysAuthManager authManager;
    private final MediaAssetFetcher assetFetcher;
    private final TranscodePayloadBuilder payloadBuilder;
    private final TranscodeExecutor executor;
    private final TranscodeGovernanceManager governance;

    public StreamTranscoderService(
            String clientId,
            String clientSecret,
            String genesysRegion,
            String mediaServerUrl
    ) {
        this.authManager = new GenesysAuthManager(clientId, clientSecret);
        this.assetFetcher = new MediaAssetFetcher(null, genesysRegion);
        this.payloadBuilder = new TranscodePayloadBuilder();
        this.executor = new TranscodeExecutor(mediaServerUrl);
        this.governance = new TranscodeGovernanceManager();
    }

    public void runTranscodingPipeline() throws Exception {
        String token = authManager.getAccessToken();
        assetFetcher.recordingApi.getApiClient().setAccessToken(token);

        RecordingSearchResponse searchResponse = assetFetcher.fetchPendingRecordings();
        List<RecordingReference> recordings = searchResponse.getEntities();

        if (recordings == null || recordings.isEmpty()) {
            logger.info("No pending recordings found");
            return;
        }

        for (RecordingReference recording : recordings) {
            String recordingId = recording.getId();
            String streamUrl = recording.getMediaUrl() != null ? recording.getMediaUrl() : "https://fallback.stream.url";
            
            logger.info("Processing recording: {}", recordingId);
            long startTime = Instant.now().toEpochMilli();

            try {
                String payload = payloadBuilder.buildPayload(recordingId, streamUrl, 1280, 30.0);
                String response = executor.executeTranscode(token, payload);
                
                long duration = Instant.now().toEpochMilli() - startTime;
                governance.recordTranscodeEvent(recordingId, streamUrl, true, duration);
                logger.info("Transcode submitted successfully for {}: {}", recordingId, response);
            } catch (Exception e) {
                long duration = Instant.now().toEpochMilli() - startTime;
                governance.recordTranscodeEvent(recordingId, streamUrl, false, duration);
                logger.error("Transcode failed for {}: {}", recordingId, e.getMessage());
            }
        }
    }

    public static void main(String[] args) {
        try {
            StreamTranscoderService service = new StreamTranscoderService(
                    "YOUR_CLIENT_ID",
                    "YOUR_CLIENT_SECRET",
                    "us-east-1",
                    "https://media-server.yourdomain.com"
            );
            service.runTranscodingPipeline();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

Common Errors & Debugging

Error: 401 Unauthorized

• What causes it: The OAuth token is missing, expired, or the client credentials are invalid.
• How to fix it: Verify the client ID and secret match a registered Genesys Cloud application. Ensure the token refresh logic runs before expiration. Check that the Authorization header uses the Bearer scheme.
• Code showing the fix: The GenesysAuthManager class caches tokens and refreshes them when System.currentTimeMillis() approaches tokenExpiryEpoch - 60_000.

Error: 403 Forbidden

• What causes it: The OAuth token lacks the required scopes, or the application is not authorized to access media assets.
• How to fix it: Add media:read, recordings:read, and media:write to the OAuth application scopes in the Genesys Cloud admin console. Revoke and regenerate the token after scope changes.
• Code showing the fix: Update the OAuth application configuration in Genesys Cloud. The Java code does not change, but the token request must include the updated scope set if using custom grant flows.

Error: 429 Too Many Requests

• What causes it: The external media server or Genesys Cloud API enforces rate limits. Rapid concurrent PUT operations trigger cascading throttling.
• How to fix it: Implement exponential backoff with jitter. The TranscodeExecutor class retries up to three times with doubling backoff intervals. Add a circuit breaker pattern in production to halt submissions during sustained throttling.
• Code showing the fix: The retry loop in executeTranscode sleeps for backoffMs, multiplies by two on each iteration, and throws after maxRetries.

Error: Payload Validation Failure

• What causes it: Bitrate exceeds buffer capacity, frame rate falls outside supported ranges, or CPU load constraints are violated.
• How to fix it: Adjust the targetBitrateKbps and targetFrameRate parameters. The validateConstraints method enforces 128-4096 kbps and 24-60 fps. High bitrate combined with high frame rate triggers a CPU load exception.
• Code showing the fix: Modify the buildPayload call to use 1280 kbps and 30.0 fps, which satisfies the constraint pipeline.

Official References

• Genesys Cloud Media API Documentation
• Genesys Cloud Recordings API Documentation
• Genesys Cloud Java SDK Reference
• OAuth 2.0 Client Credentials Flow
• OkHttp Retry and Backoff Patterns