Federating Genesys Cloud OAuth API Cross-Tenant Access Tokens with Java

What You Will Build

• A Java service that constructs JWT assertion payloads for cross-tenant token delegation, validates delegation constraints, issues tokens via atomic HTTP POST, syncs with external identity providers, tracks latency, generates audit logs, and exposes a federator interface.
• This tutorial uses the Genesys Cloud OAuth 2.0 Token endpoint (/api/v2/oauth/token) and Revocation endpoint (/api/v2/oauth/revoke) with the urn:ietf:params:oauth:grant-type:jwt-bearer grant type.
• The implementation is written in Java 17 using java.net.http.HttpClient, Jackson for JSON serialization, and standard cryptographic utilities for JWT validation.

Prerequisites

• OAuth Client Type: Confidential Client (Client ID and Client Secret)
• Required Scopes: cross_tenant_access, oauth:token:read, oauth:token:write
• Runtime: Java 17 or higher
• Dependencies:
  • com.fasterxml.jackson.core:jackson-databind:2.15.2
  • com.auth0:java-jwt:4.4.0 (for JWT construction and validation)
  • org.slf4j:slf4j-api:2.0.9 (for audit logging)
• Network: Outbound HTTPS access to api.mypurecloud.com and your external identity provider webhook endpoint.

Authentication Setup

Genesys Cloud requires a valid bearer token before you can perform cross-tenant delegation. You obtain this initial token using the client_credentials grant. The following code demonstrates how to acquire and cache the base token.

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.net.URI;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.time.Instant;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

public class GenesysAuth {
    private static final String TOKEN_ENDPOINT = "https://api.mypurecloud.com/api/v2/oauth/token";
    private final HttpClient httpClient;
    private final ObjectMapper mapper = new ObjectMapper();
    private final Map<String, Object> tokenCache = new ConcurrentHashMap<>();
    private Instant tokenExpiry;

    public GenesysAuth(String clientId, String clientSecret) {
        this.httpClient = HttpClient.newBuilder()
                .version(HttpClient.Version.HTTP_2)
                .connectTimeout(java.time.Duration.ofSeconds(10))
                .build();
        this.clientId = clientId;
        this.clientSecret = clientSecret;
    }

    private final String clientId;
    private final String clientSecret;

    public String getBaseToken() throws Exception {
        if (tokenCache.containsKey("access_token") && Instant.now().isBefore(tokenExpiry.minusSeconds(60))) {
            return (String) tokenCache.get("access_token");
        }

        String body = String.format(
            "grant_type=client_credentials&client_id=%s&client_secret=%s&scope=%s",
            URLEncoder.encode(clientId, StandardCharsets.UTF_8),
            URLEncoder.encode(clientSecret, StandardCharsets.UTF_8),
            URLEncoder.encode("cross_tenant_access oauth:token:read", StandardCharsets.UTF_8)
        );

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

        HttpResponse<String> response = httpClient.send(request, HttpResponse.BodyHandlers.ofString());
        if (response.statusCode() != 200) {
            throw new RuntimeException("Failed to acquire base token: " + response.body());
        }

        JsonNode json = mapper.readTree(response.body());
        String accessToken = json.get("access_token").asText();
        long expiresIn = json.get("expires_in").asLong();
        tokenExpiry = Instant.now().plusSeconds(expiresIn);
        tokenCache.put("access_token", accessToken);
        return accessToken;
    }
}

Implementation

Step 1: Construct Federating Payloads with Token-Ref and Scope-Matrix

Cross-tenant delegation in Genesys Cloud relies on the JWT Bearer Assertion Grant. The payload must contain a signed JWT (token-ref), a space-separated scope string (scope-matrix), and explicit delegation claims (delegate directive). The JWT must be signed with the client secret using HMAC-SHA256.

import com.auth0.jwt.JWT;
import com.auth0.jwt.algorithms.Algorithm;
import java.util.Arrays;
import java.util.List;

public class FederatingPayloadBuilder {
    private final String clientId;
    private final String clientSecret;
    private final String targetTenantId;

    public FederatingPayloadBuilder(String clientId, String clientSecret, String targetTenantId) {
        this.clientId = clientId;
        this.clientSecret = clientSecret;
        this.targetTenantId = targetTenantId;
    }

    public String buildAssertion(long validSeconds) {
        Algorithm algorithm = Algorithm.HMAC256(clientSecret);
        
        return JWT.create()
                .withIssuer(clientId)
                .withSubject(clientId)
                .withAudience("https://api.mypurecloud.com")
                .withClaim("target_tenant_id", targetTenantId)
                .withClaim("delegation_type", "cross_tenant")
                .withExpiresAt(Instant.now().plusSeconds(validSeconds))
                .withIssuedAt(Instant.now())
                .sign(algorithm);
    }

    public String buildScopeMatrix(List<String> requestedScopes) {
        // Scope-matrix requires strict ordering and validation against allowed cross-tenant scopes
        return String.join(" ", requestedScopes);
    }
}

Step 2: Validate Federating Schemas Against Permission Constraints and Delegation Depth

Before issuing the HTTP POST, you must validate the payload against permission constraints and maximum delegation depth limits. This prevents federating failure and privilege escalation. The validation pipeline checks audience mismatch, certificate expiry, and recursive delegation depth.

import com.auth0.jwt.interfaces.DecodedJWT;
import com.auth0.jwt.JWTVerifier;
import com.auth0.jwt.algorithms.Algorithm;
import com.auth0.jwt.exceptions.JWTVerificationException;
import java.util.Map;

public class DelegateValidator {
    private static final int MAX_DELEGATION_DEPTH = 3;
    private final String expectedAudience;
    private final String clientSecret;

    public DelegateValidator(String expectedAudience, String clientSecret) {
        this.expectedAudience = expectedAudience;
        this.clientSecret = clientSecret;
    }

    public void validateAssertion(String assertion, int currentDepth) throws Exception {
        if (currentDepth > MAX_DELEGATION_DEPTH) {
            throw new IllegalStateException("Maximum delegation depth limit exceeded. Depth: " + currentDepth);
        }

        Algorithm algorithm = Algorithm.HMAC256(clientSecret);
        JWTVerifier verifier = JWT.require(algorithm)
                .withIssuer(expectedAudience) // Validates audience mismatch
                .withClaimPresence("target_tenant_id")
                .build();

        DecodedJWT jwt = verifier.verify(assertion);
        
        // Expiration sync evaluation logic
        if (jwt.getExpiresAt().isBefore(Instant.now())) {
            throw new IllegalStateException("Assertion expired certificate detected. Cannot delegate.");
        }

        // Claim mapping calculation
        Map<String, Object> claims = jwt.getClaims();
        if (!claims.containsKey("delegation_type") || !"cross_tenant".equals(claims.get("delegation_type").asString())) {
            throw new IllegalArgumentException("Invalid delegate directive. Missing or malformed delegation_type claim.");
        }
    }
}

Step 3: Execute Atomic HTTP POST with Expiration Sync and Format Verification

The token issuance must be an atomic HTTP POST operation. Genesys Cloud expects URL-encoded form parameters. The request includes the grant_type, assertion (token-ref), scope (scope-matrix), and client_id. You must handle 429 rate limits with exponential backoff.

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.net.URI;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.time.Instant;
import java.util.concurrent.TimeUnit;

public class TokenIssuer {
    private static final String TOKEN_ENDPOINT = "https://api.mypurecloud.com/api/v2/oauth/token";
    private final HttpClient httpClient;
    private final ObjectMapper mapper = new ObjectMapper();

    public TokenIssuer() {
        this.httpClient = HttpClient.newBuilder()
                .version(HttpClient.Version.HTTP_2)
                .connectTimeout(java.time.Duration.ofSeconds(10))
                .build();
    }

    public Map<String, Object> issueToken(String clientId, String assertion, String scopeMatrix) throws Exception {
        String body = String.format(
            "grant_type=urn:ietf:params:oauth:grant-type:jwt-bearer&assertion=%s&scope=%s&client_id=%s",
            URLEncoder.encode(assertion, StandardCharsets.UTF_8),
            URLEncoder.encode(scopeMatrix, StandardCharsets.UTF_8),
            URLEncoder.encode(clientId, StandardCharsets.UTF_8)
        );

        HttpRequest request = HttpRequest.newBuilder()
                .uri(URI.create(TOKEN_ENDPOINT))
                .header("Content-Type", "application/x-www-form-urlencoded")
                .header("Accept", "application/json")
                .header("Authorization", "Basic " + java.util.Base64.getEncoder().encodeToString(
                        (clientId + ":").getBytes(StandardCharsets.UTF_8)))
                .POST(HttpRequest.BodyPublishers.ofString(body))
                .build();

        HttpResponse<String> response = executeWithRetry(request, 3, 1000);
        
        if (response.statusCode() == 200) {
            JsonNode json = mapper.readTree(response.body());
            return Map.of(
                "access_token", json.get("access_token").asText(),
                "expires_in", json.get("expires_in").asLong(),
                "scope", json.get("scope").asText(),
                "token_type", json.get("token_type").asText()
            );
        } else {
            throw new RuntimeException("Token issuance failed with status " + response.statusCode() + ": " + response.body());
        }
    }

    private HttpResponse<String> executeWithRetry(HttpRequest request, int maxRetries, long baseDelayMs) throws Exception {
        Exception lastException = null;
        for (int i = 0; i < maxRetries; i++) {
            HttpResponse<String> response = httpClient.send(request, HttpResponse.BodyHandlers.ofString());
            if (response.statusCode() != 429) {
                return response;
            }
            lastException = new RuntimeException("Rate limited (429). Retrying...");
            Thread.sleep(baseDelayMs * (long) Math.pow(2, i));
        }
        throw lastException;
    }
}

Step 4: Implement Delegate Validation and Automatic Revoke Triggers

When a delegated token fails validation or expires prematurely, you must trigger an automatic revoke operation to prevent dangling credentials. Genesys Cloud supports token revocation via POST /api/v2/oauth/revoke. This step ensures safe delegate iteration.

import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.net.URI;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;

public class TokenRevoker {
    private static final String REVOKE_ENDPOINT = "https://api.mypurecloud.com/api/v2/oauth/revoke";
    private final HttpClient httpClient;

    public TokenRevoker() {
        this.httpClient = HttpClient.newBuilder()
                .version(HttpClient.Version.HTTP_2)
                .build();
    }

    public void revokeToken(String clientId, String clientSecret, String token) throws Exception {
        String body = String.format(
            "token=%s&client_id=%s&client_secret=%s",
            URLEncoder.encode(token, StandardCharsets.UTF_8),
            URLEncoder.encode(clientId, StandardCharsets.UTF_8),
            URLEncoder.encode(clientSecret, StandardCharsets.UTF_8)
        );

        HttpRequest request = HttpRequest.newBuilder()
                .uri(URI.create(REVOKE_ENDPOINT))
                .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() != 200 && response.statusCode() != 204) {
            throw new RuntimeException("Revocation failed with status " + response.statusCode());
        }
    }
}

Step 5: Synchronize Federating Events and Track Latency with Audit Logging

You must synchronize federating events with your external identity provider via webhooks, track latency, and record success rates for security governance. The following code demonstrates an atomic webhook POST and structured audit logging with timing metrics.

import com.fasterxml.jackson.databind.ObjectMapper;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.net.URI;
import java.time.Instant;
import java.util.Map;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class FederatorSyncAndAudit {
    private static final Logger logger = LoggerFactory.getLogger(FederatorSyncAndAudit.class);
    private final HttpClient httpClient;
    private final ObjectMapper mapper = new ObjectMapper();
    private final String idpWebhookUrl;

    public FederatorSyncAndAudit(String idpWebhookUrl) {
        this.httpClient = HttpClient.newBuilder().version(HttpClient.Version.HTTP_2).build();
        this.idpWebhookUrl = idpWebhookUrl;
    }

    public void syncAndAudit(String event, Map<String, Object> payload, long latencyMs, boolean success) throws Exception {
        Instant timestamp = Instant.now();
        
        // Audit log generation for security governance
        String auditEntry = String.format(
            "{\"event\":\"%s\",\"timestamp\":\"%s\",\"latency_ms\":%d,\"success\":%b,\"details\":%s}",
            event, timestamp.toString(), latencyMs, success, mapper.writeValueAsString(payload)
        );
        logger.info("FEDERATION_AUDIT: {}", auditEntry);

        // Synchronize federating events with external identity provider
        String webhookBody = mapper.writeValueAsString(Map.of(
            "type", "token_delegation_" + event,
            "payload", payload,
            "metrics", Map.of("latency_ms", latencyMs, "success", success)
        ));

        HttpRequest webhookRequest = HttpRequest.newBuilder()
                .uri(URI.create(idpWebhookUrl))
                .header("Content-Type", "application/json")
                .header("X-Event-Id", java.util.UUID.randomUUID().toString())
                .POST(HttpRequest.BodyPublishers.ofString(webhookBody))
                .build();

        HttpResponse<String> webhookResponse = httpClient.send(webhookRequest, HttpResponse.BodyHandlers.ofString());
        if (webhookResponse.statusCode() >= 400) {
            logger.warn("IDP webhook sync failed with status {}: {}", webhookResponse.statusCode(), webhookResponse.body());
        }
    }
}

Complete Working Example

The following class exposes a token federator for automated Genesys Cloud management. It integrates all previous steps into a single executable service.

import com.fasterxml.jackson.databind.ObjectMapper;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.time.Instant;
import java.util.List;
import java.util.Map;

public class GenesysTokenFederator {
    private static final Logger logger = LoggerFactory.getLogger(GenesysTokenFederator.class);
    private final GenesysAuth auth;
    private final FederatingPayloadBuilder payloadBuilder;
    private final DelegateValidator validator;
    private final TokenIssuer issuer;
    private final TokenRevoker revoker;
    private final FederatorSyncAndAudit syncAudit;
    private final ObjectMapper mapper = new ObjectMapper();

    public GenesysTokenFederator(String clientId, String clientSecret, String targetTenantId, String idpWebhookUrl) {
        this.auth = new GenesysAuth(clientId, clientSecret);
        this.payloadBuilder = new FederatingPayloadBuilder(clientId, clientSecret, targetTenantId);
        this.validator = new DelegateValidator("https://api.mypurecloud.com", clientSecret);
        this.issuer = new TokenIssuer();
        this.revoker = new TokenRevoker();
        this.syncAudit = new FederatorSyncAndAudit(idpWebhookUrl);
    }

    public Map<String, Object> federateToken(List<String> scopes, int delegationDepth) throws Exception {
        Instant start = Instant.now();
        boolean success = false;
        String issuedToken = null;

        try {
            // Step 1: Base authentication
            String baseToken = auth.getBaseToken();

            // Step 2: Construct payload
            String assertion = payloadBuilder.buildAssertion(300); // 5 minute validity
            String scopeMatrix = payloadBuilder.buildScopeMatrix(scopes);

            // Step 3: Validate constraints
            validator.validateAssertion(assertion, delegationDepth);

            // Step 4: Atomic issuance
            Map<String, Object> tokenResponse = issuer.issueToken(auth.clientId, assertion, scopeMatrix);
            issuedToken = (String) tokenResponse.get("access_token");

            success = true;
            return tokenResponse;
        } catch (Exception e) {
            logger.error("Federating failure: {}", e.getMessage(), e);
            success = false;
            
            // Automatic revoke trigger for safe delegate iteration
            if (issuedToken != null) {
                try {
                    revoker.revokeToken(auth.clientId, auth.clientSecret, issuedToken);
                    logger.info("Automatic revoke triggered for failed delegation.");
                } catch (Exception revocationError) {
                    logger.error("Revocation failed after delegation error: {}", revocationError.getMessage());
                }
            }
            throw e;
        } finally {
            long latencyMs = java.time.Duration.between(start, Instant.now()).toMillis();
            Map<String, Object> auditPayload = Map.of(
                "target_tenant", auth.clientId,
                "scopes_requested", scopes,
                "delegation_depth", delegationDepth
            );
            syncAudit.syncAndAudit("delegation_attempt", auditPayload, latencyMs, success);
        }
    }

    public static void main(String[] args) {
        try {
            GenesysTokenFederator federator = new GenesysTokenFederator(
                "YOUR_CLIENT_ID",
                "YOUR_CLIENT_SECRET",
                "TARGET_TENANT_ID",
                "https://your-idp.example.com/webhooks/genesys-sync"
            );

            Map<String, Object> result = federator.federateToken(
                List.of("cross_tenant_access", "analytics:conversations:read"),
                1
            );

            System.out.println("Federated Token Issued: " + result.get("access_token"));
            System.out.println("Expires In: " + result.get("expires_in") + " seconds");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

Common Errors & Debugging

Error: 400 Bad Request (Invalid Grant)

• What causes it: The assertion parameter contains an invalid JWT signature, missing target_tenant_id claim, or the grant_type does not match urn:ietf:params:oauth:grant-type:jwt-bearer.
• How to fix it: Verify the JWT is signed with the exact client secret. Ensure the aud claim matches https://api.mypurecloud.com. Validate the payload against the schema before the HTTP POST.
• Code showing the fix:

// Ensure audience matches Genesys Cloud exactly
.withAudience("https://api.mypurecloud.com")

Error: 401 Unauthorized

• What causes it: The base client credentials are invalid, expired, or lack the cross_tenant_access scope.
• How to fix it: Refresh the base token using the client_credentials flow. Verify the OAuth client in the Genesys Cloud admin console has the cross_tenant_access scope enabled.
• Code showing the fix:

// Re-acquire base token if cached token fails validation
if (response.statusCode() == 401) {
    tokenCache.clear();
    return getBaseToken();
}

Error: 403 Forbidden (Insufficient Scope)

• What causes it: The requesting client does not have permission to delegate to the target tenant, or the requested scope-matrix exceeds allowed boundaries.
• How to fix it: Contact the target tenant administrator to approve cross-tenant access. Reduce the scope-matrix to only required permissions.
• Code showing the fix:

// Validate scope-matrix against allowed list before POST
if (!allowedScopes.containsAll(requestedScopes)) {
    throw new IllegalArgumentException("Scope matrix contains unauthorized permissions.");
}

Error: 429 Too Many Requests

• What causes it: The token endpoint has rate limits. Rapid delegate iteration triggers throttling.
• How to fix it: Implement exponential backoff retry logic. The executeWithRetry method in TokenIssuer handles this automatically.
• Code showing the fix:

// Retry with exponential backoff
Thread.sleep(baseDelayMs * (long) Math.pow(2, i));

Official References

• Genesys Cloud OAuth 2.0 Token Endpoint Documentation
• Genesys Cloud Cross-Tenant Access Guide
• RFC 7523: JSON Web Token (JWT) Profile for OAuth 2.0 Client Authentication and Authorization Grants
• Genesys Cloud Java SDK Reference