Sending Genesys Cloud Webchat Messages via WebSocket in Java

What You Will Build

A Java module that constructs, validates, encrypts, and transmits messages to Genesys Cloud Webchat over WebSocket, tracks delivery acknowledgments, logs audit trails, and exposes a reusable sender interface. This tutorial uses the Genesys Cloud Java SDK for OAuth and REST operations, combined with java.net.http.WebSocket for real-time message transmission. The language covered is Java 17+.

Prerequisites

• OAuth Client Credentials grant with scopes: webchat:send, webchat:read, webhooks:write, webhooks:read
• Genesys Cloud Java SDK version 14.0.0+ (com.mypurecloud.api.client)
• Java 17 runtime
• Maven or Gradle for dependency management
• javax.crypto (JDK built-in) for payload encryption
• java.net.http (JDK built-in) for WebSocket and REST

Add the SDK dependency to your pom.xml:

<dependency>
    <groupId>com.mypurecloud.api.client</groupId>
    <artifactId>genesyscloud-java-sdk</artifactId>
    <version>14.0.0</version>
</dependency>

Authentication Setup

Genesys Cloud requires a bearer token for all API and WebSocket connections. The Java SDK handles token acquisition and automatic refresh. You must configure the ApiClient with your environment region, client ID, and client secret.

import com.mypurecloud.api.client.ApiClient;
import com.mypurecloud.api.client.auth.OAuthClient;
import com.mypurecloud.api.client.auth.OAuthConfig;

public class GenesysWebchatSender {
    private static final String REGION = "us-east-1";
    private static final String CLIENT_ID = "your-client-id";
    private static final String CLIENT_SECRET = "your-client-secret";
    private static final String[] REQUIRED_SCOPES = {"webchat:send", "webchat:read", "webhooks:write"};

    private final ApiClient apiClient;

    public GenesysWebchatSender() throws Exception {
        OAuthConfig oAuthConfig = new OAuthConfig(REGION, CLIENT_ID, CLIENT_SECRET);
        apiClient = new ApiClient(REGION);
        apiClient.setOAuthClient(new OAuthClient(oAuthConfig, apiClient));
        
        // Force initial token fetch to validate credentials
        apiClient.getAccessToken();
        System.out.println("OAuth token acquired successfully. Scopes: " + String.join(", ", REQUIRED_SCOPES));
    }
}

The OAuthClient caches the access token and automatically refreshes it before expiration. If the refresh fails, subsequent API calls will throw a 401 Unauthorized exception, which the sender must catch and handle.

Implementation

Step 1: WebSocket Connection and Handshake

The Webchat v2 API uses a WebSocket endpoint for real-time messaging. The handshake requires the OAuth bearer token and specific Genesys headers. The connection must remain open for the duration of the chat session.

import java.net.URI;
import java.net.http.WebSocket;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.TimeUnit;

public class GenesysWebchatSender {
    // ... previous code ...
    
    private WebSocket webSocket;
    private final ConcurrentHashMap<String, CompletableFuture<String>> pendingAcks = new ConcurrentHashMap<>();
    private volatile long lastHeartbeat = System.currentTimeMillis();

    public void establishWebsocket() throws Exception {
        String wsUrl = "wss://webchat-api." + REGION + ".mypurecloud.com/webchat/v1";
        WebSocket.Builder builder = WebSocket.newBuilder();
        
        builder.header("Authorization", "Bearer " + apiClient.getAccessToken());
        builder.header("X-Genesys-Client-Version", "14.0.0-java");
        builder.header("Content-Type", "application/json");
        
        webSocket = builder.buildAsync(
            URI.create(wsUrl),
            new WebSocket.Listener() {
                @Override
                public WebSocket.Listener onOpen(WebSocket webSocket) {
                    System.out.println("WebSocket connected to Genesys Cloud Webchat");
                    return this;
                }

                @Override
                public void onText(WebSocket webSocket, CharSequence data, boolean last) {
                    String payload = data.toString();
                    handleIncomingMessage(payload);
                }

                @Override
                public void onError(WebSocket webSocket, Throwable error) {
                    System.err.println("WebSocket error: " + error.getMessage());
                }

                @Override
                public void onClose(WebSocket webSocket, int statusCode, String reason) {
                    System.out.println("WebSocket closed: " + statusCode + " - " + reason);
                    pendingAcks.values().forEach(f -> f.completeExceptionally(
                        new RuntimeException("WebSocket closed: " + reason)));
                }
            }
        ).join();
    }

    private void handleIncomingMessage(String payload) {
        // Track server pings for session expiry verification
        if (payload.contains("\"type\":\"ping\"")) {
            lastHeartbeat = System.currentTimeMillis();
            webSocket.sendText("{\"type\":\"pong\"}", true);
            return;
        }

        // Resolve ACK for sent messages
        if (payload.contains("\"type\":\"ack\"")) {
            String msgRef = extractField(payload, "ref");
            if (msgRef != null && pendingAcks.containsKey(msgRef)) {
                pendingAcks.remove(msgRef).complete("ack");
            }
        }
    }

    private String extractField(String json, String key) {
        // Simple JSON field extraction for tutorial purposes
        // In production, use Jackson or Gson
        int start = json.indexOf("\"" + key + "\":\"") + key.length() + 3;
        int end = json.indexOf("\"", start);
        return (start > 0 && end > start) ? json.substring(start, end) : null;
    }
}

Step 2: Payload Construction and Validation Pipeline

Genesys Cloud enforces strict schema constraints. The maximum text length is 4000 characters. You must validate the message reference, text content, and transmit directive before encryption. The validation pipeline also checks for profanity and verifies session expiry.

import java.util.Set;

public class GenesysWebchatSender {
    // ... previous code ...
    
    private static final int MAX_MESSAGE_LENGTH = 4000;
    private static final Set<String> PROFANITY_LIST = Set.of("badword1", "badword2", "badword3");
    private static final long SESSION_EXPIRY_MS = 30_000; // 30 seconds without ping/pong

    public String constructAndValidatePayload(String messageRef, String textMatrix) throws Exception {
        // Session expiry verification
        if (System.currentTimeMillis() - lastHeartbeat > SESSION_EXPIRY_MS) {
            throw new IllegalStateException("Webchat session expired. Reconnect required.");
        }

        // Maximum message length validation
        if (textMatrix.length() > MAX_MESSAGE_LENGTH) {
            throw new IllegalArgumentException("Text exceeds maximum-message-length limit of " + MAX_MESSAGE_LENGTH);
        }

        // Profanity filter checking
        for (String word : PROFANITY_LIST) {
            if (textMatrix.toLowerCase().contains(word)) {
                throw new SecurityException("Message failed profanity-filter checking pipeline.");
            }
        }

        // Construct transmit directive payload
        String payload = String.format(
            "{\"type\":\"message\",\"id\":\"%s\",\"content\":{\"text\":\"%s\"},\"metadata\":{\"source\":\"automated-java-sender\"}}",
            messageRef,
            textMatrix.replace("\"", "\\\"").replace("\n", "\\n")
        );

        return payload;
    }
}

Step 3: Encryption Calculation and Atomic WebSocket SEND

Transport layer encryption is handled by WSS. Application-layer encryption adds an extra security boundary. The sender encrypts the payload using AES-GCM, transmits it atomically via WebSocket, and waits for the automatic ACK trigger.

import javax.crypto.Cipher;
import javax.crypto.spec.GCMParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import java.nio.charset.StandardCharsets;
import java.util.Base64;
import java.util.UUID;

public class GenesysWebchatSender {
    // ... previous code ...
    
    // In production, retrieve from a secrets manager
    private static final String ENCRYPTION_KEY = "your-32-character-secret-key-here!!"; 

    public String encryptPayload(String plainPayload) throws Exception {
        byte[] keyBytes = ENCRYPTION_KEY.getBytes(StandardCharsets.UTF_8);
        SecretKeySpec keySpec = new SecretKeySpec(keyBytes, "AES");
        Cipher cipher = Cipher.getInstance("AES/GCM/NoPadding");
        
        byte[] iv = new byte[12];
        java.security.SecureRandom.getInstanceStrong().nextBytes(iv);
        cipher.init(Cipher.ENCRYPT_MODE, keySpec, new GCMParameterSpec(128, iv));
        
        byte[] encrypted = cipher.doFinal(plainPayload.getBytes(StandardCharsets.UTF_8));
        byte[] combined = new byte[iv.length + encrypted.length];
        System.arraycopy(iv, 0, combined, 0, iv.length);
        System.arraycopy(encrypted, 0, combined, iv.length, encrypted.length);
        
        return Base64.getEncoder().encodeToString(combined);
    }

    public CompletableFuture<String> sendEncryptedMessage(String messageRef, String textMatrix) throws Exception {
        String validatedPayload = constructAndValidatePayload(messageRef, textMatrix);
        String encryptedPayload = encryptPayload(validatedPayload);
        
        CompletableFuture<String> ackFuture = new CompletableFuture<>();
        pendingAcks.put(messageRef, ackFuture);
        
        long sendTimestamp = System.currentTimeMillis();
        
        // Atomic WebSocket SEND operation
        webSocket.sendText(encryptedPayload, true);
        
        // Format verification and automatic ack trigger
        return ackFuture.orTimeout(10, TimeUnit.SECONDS)
            .thenApply(ack -> {
                long latency = System.currentTimeMillis() - sendTimestamp;
                logAuditEvent(messageRef, true, latency);
                trackMetrics(latency, true);
                return "Message delivered successfully. Latency: " + latency + "ms";
            })
            .exceptionally(ex -> {
                pendingAcks.remove(messageRef);
                long latency = System.currentTimeMillis() - sendTimestamp;
                logAuditEvent(messageRef, false, latency);
                trackMetrics(latency, false);
                throw new RuntimeException("Transmit failed: " + ex.getMessage());
            });
    }
}

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

The sender tracks latency and success rates, generates audit logs, and registers a webhook to synchronize transmitted messages with an external chat log system.

import java.util.concurrent.atomic.AtomicInteger;
import java.util.logging.Logger;
import java.util.logging.Level;

public class GenesysWebchatSender {
    // ... previous code ...
    
    private static final Logger AUDIT_LOGGER = Logger.getLogger("GenesysWebchatAudit");
    private final AtomicInteger totalSent = new AtomicInteger(0);
    private final AtomicInteger successfulSent = new AtomicInteger(0);
    private long totalLatency = 0;

    private void trackMetrics(long latency, boolean success) {
        totalSent.incrementAndGet();
        if (success) successfulSent.incrementAndGet();
        totalLatency += latency;
    }

    public double getTransmitSuccessRate() {
        int sent = totalSent.get();
        return sent == 0 ? 0.0 : (double) successfulSent.get() / sent;
    }

    public double getAverageLatency() {
        int sent = totalSent.get();
        return sent == 0 ? 0.0 : (double) totalLatency / sent;
    }

    private void logAuditEvent(String messageRef, boolean success, long latency) {
        AUDIT_LOGGER.info(String.format(
            "AUDIT | msgRef=%s | success=%s | latency=%dms | successRate=%.2f | avgLatency=%.2f",
            messageRef, success, latency, getTransmitSuccessRate(), getAverageLatency()
        ));
    }

    public void registerExternalChatWebhook(String targetUrl) throws Exception {
        // Synchronize sending events with external-chat-log via message transmitted webhooks
        String webhookPayload = String.format(
            "{\"name\":\"ExternalChatSync\",\"enabled\":true,\"targetUrl\":\"%s\",\"matchData\":{\"event\":\"chat.transcript\"},\"condition\":null,\"requestType\":\"POST\",\"requestHeaders\":{\"Content-Type\":\"application/json\"}}",
            targetUrl
        );
        
        // Use SDK for REST webhook registration
        // Note: In production, use the WebhooksApi class from the SDK
        System.out.println("Webhook registration payload generated. Submit to POST /api/v2/webhooks with webhooks:write scope.");
    }
}

Complete Working Example

import java.util.concurrent.ExecutionException;

public class GenesysWebchatRunner {
    public static void main(String[] args) {
        try {
            GenesysWebchatSender sender = new GenesysWebchatSender();
            sender.establishWebsocket();
            
            // Register webhook for external log synchronization
            sender.registerExternalChatWebhook("https://your-external-system.com/api/chat-log");
            
            // Send message with automatic ACK tracking
            String msgRef = UUID.randomUUID().toString();
            System.out.println("Sending message: " + msgRef);
            
            CompletableFuture<String> result = sender.sendEncryptedMessage(msgRef, "Hello Genesys Cloud Webchat API");
            
            try {
                System.out.println(result.get());
            } catch (ExecutionException e) {
                System.err.println("Transmit failed: " + e.getCause().getMessage());
            }
            
            System.out.println("Overall success rate: " + String.format("%.2f%%", sender.getTransmitSuccessRate() * 100));
            System.out.println("Average latency: " + String.format("%.2fms", sender.getAverageLatency()));
            
        } catch (Exception e) {
            System.err.println("Initialization or execution failed: " + e.getMessage());
            e.printStackTrace();
        }
    }
}

Common Errors & Debugging

Error: 401 Unauthorized or 403 Forbidden

• What causes it: Invalid client credentials, missing OAuth scopes, or expired token. The WebSocket handshake fails if the bearer token lacks webchat:send.
• How to fix it: Verify the client ID and secret in the Genesys Cloud admin console. Ensure the OAuth client has the webchat:send scope assigned. Call apiClient.getAccessToken() before initializing the WebSocket to force a fresh token fetch.
• Code showing the fix:

try {
    apiClient.getAccessToken();
} catch (com.mypurecloud.api.client.auth.exception.OAuthException e) {
    System.err.println("OAuth failure: " + e.getMessage());
    throw e;
}

Error: WebSocket Close 1008 or 4000

• What causes it: Malformed JSON payload, missing type field, or exceeding maximum-message-length constraints. Genesys Cloud rejects messages that fail schema validation.
• How to fix it: Validate the payload structure before encryption. Ensure the type field matches "message" and the content.text field is a valid string. Run the validation pipeline before every send.
• Code showing the fix:

if (!payload.startsWith("{\"type\":\"message\"") || payload.length() > MAX_MESSAGE_LENGTH + 200) {
    throw new IllegalArgumentException("Payload failed webchat-constraints validation.");
}

Error: ACK Timeout or 429 Rate Limit Cascade

• What causes it: Sending messages faster than the WebSocket channel can process, or network latency causing ACK delays. Genesys Cloud may return 429 on REST calls if webhook registration is throttled.
• How to fix it: Implement exponential backoff for REST calls. For WebSocket sends, queue messages and process them sequentially based on ACK completion. The orTimeout(10, TimeUnit.SECONDS) in the sender handles ACK delays gracefully.
• Code showing the fix:

// Retry logic for 429 on REST calls
HttpClient client = HttpClient.newHttpClient();
HttpRequest request = HttpRequest.newBuilder(URI.create("https://api." + REGION + ".mypurecloud.com/api/v2/webhooks"))
    .header("Authorization", "Bearer " + apiClient.getAccessToken())
    .POST(HttpRequest.BodyPublishers.ofString(webhookPayload))
    .build();

HttpResponse<String> response = client.send(request, HttpResponse.BodyHandlers.ofString());
if (response.statusCode() == 429) {
    Thread.sleep(1000); // Backoff before retry
}

Official References

• Genesys Cloud Webchat API Documentation
• Genesys Cloud Java SDK Reference
• OAuth 2.0 Client Credentials Flow
• Webhook Configuration API