Bulk-Update Genesys Cloud User Custom Attributes via SCIM 2.0 PATCH with Java HttpClient

What You Will Build

• You will build a Java application that updates custom attributes for hundreds or thousands of Genesys Cloud users simultaneously without blocking the main thread.
• The code uses the Genesys Cloud SCIM 2.0 PATCH endpoint (/api/v2/scim/Users/{userId}) to apply attribute changes in parallel batches.
• The implementation is written in Java 17 using the built-in java.net.http.HttpClient with connection pooling, concurrent execution, and exponential backoff for rate limits.

Prerequisites

• OAuth client type and required scopes: Confidential client (Client Credentials grant). Required scope: scim:users:write
• SDK version or API version: Genesys Cloud API v2 (raw HTTP, no SDK wrapper required)
• Language/runtime requirements: Java 17 or later
• External dependencies: com.fasterxml.jackson.core:jackson-databind:2.15.2 (for JSON serialization)

Authentication Setup

Genesys Cloud uses OAuth 2.0 for all API access. The Client Credentials flow returns an access token that expires after one hour. You must cache the token and refresh it before expiration to avoid failed batch operations.

The following code demonstrates a thread-safe token manager that fetches credentials from environment variables, exchanges them for an access token, and handles the HTTP lifecycle.

import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.time.Duration;
import java.util.Map;
import java.util.concurrent.atomic.AtomicReference;
import com.fasterxml.jackson.databind.ObjectMapper;

public class AuthManager {
    private static final String TOKEN_ENDPOINT = "https://api.mypurecloud.com/oauth/token";
    private static final Duration TIMEOUT = Duration.ofSeconds(10);
    private static final ObjectMapper MAPPER = new ObjectMapper();
    
    private final HttpClient client;
    private final AtomicReference<String> accessToken = new AtomicReference<>();
    private final AtomicReference<Long> tokenExpiry = new AtomicReference<>(0L);

    public AuthManager() {
        this.client = HttpClient.newBuilder()
                .version(HttpClient.Version.HTTP_2)
                .connectTimeout(TIMEOUT)
                .build();
    }

    public String getAccessToken() throws Exception {
        long now = System.currentTimeMillis();
        if (accessToken.get() != null && now < tokenExpiry.get()) {
            return accessToken.get();
        }
        synchronized (this) {
            // Double-checked locking for thread safety
            if (accessToken.get() != null && now < tokenExpiry.get()) {
                return accessToken.get();
            }
            fetchToken();
            return accessToken.get();
        }
    }

    private void fetchToken() throws Exception {
        String clientId = System.getenv("GENESYS_CLIENT_ID");
        String clientSecret = System.getenv("GENESYS_CLIENT_SECRET");
        
        String body = "grant_type=client_credentials&scope=scim:users:write";
        HttpRequest request = HttpRequest.newBuilder()
                .uri(URI.create(TOKEN_ENDPOINT))
                .header("Content-Type", "application/x-www-form-urlencoded")
                .header("Authorization", "Basic " + Base64.getEncoder().encodeToString((clientId + ":" + clientSecret).getBytes()))
                .POST(HttpRequest.BodyPublishers.ofString(body))
                .timeout(TIMEOUT)
                .build();

        HttpResponse<String> response = client.send(request, HttpResponse.BodyHandlers.ofString());
        if (response.statusCode() != 200) {
            throw new RuntimeException("Token fetch failed with status " + response.statusCode() + ": " + response.body());
        }

        Map<String, Object> tokenData = MAPPER.readValue(response.body(), Map.class);
        accessToken.set((String) tokenData.get("access_token"));
        tokenExpiry.set(System.currentTimeMillis() + ((long) tokenData.get("expires_in") * 1000) - 60000); // Refresh 1 minute early
    }
}

Required OAuth Scope: scim:users:write
Expected Response (200 OK):

{
  "access_token": "eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9...",
  "token_type": "Bearer",
  "expires_in": 3600,
  "scope": "scim:users:write"
}

Implementation

Step 1: Configure HttpClient with Connection Pooling

The Java HttpClient manages connections automatically when configured with a shared ExecutorService. By providing a fixed thread pool, you enable HTTP/2 multiplexing and connection reuse across concurrent requests. This prevents the overhead of establishing new TCP/TLS handshakes for every user update.

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.net.http.HttpClient;
import java.time.Duration;

public class ScimHttpClientFactory {
    private static final int POOL_SIZE = 20;
    private static final Duration CONNECT_TIMEOUT = Duration.ofSeconds(10);
    private static final Duration READ_TIMEOUT = Duration.ofSeconds(30);

    public static HttpClient createPooledClient() {
        ExecutorService executor = Executors.newFixedThreadPool(POOL_SIZE);
        return HttpClient.newBuilder()
                .version(HttpClient.Version.HTTP_2)
                .executor(executor)
                .connectTimeout(CONNECT_TIMEOUT)
                .followRedirects(HttpClient.Redirect.NEVER)
                .build();
    }
}

Step 2: Construct SCIM 2.0 PATCH Payloads

Genesys Cloud SCIM PATCH operations require a specific JSON structure. The Operations array must contain objects with op, path, and value fields. Custom attributes are addressed using bracket notation inside the path parameter. The op value must be replace, add, or remove. This example uses replace to overwrite existing attribute values.

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

public class ScimPayloadBuilder {
    private static final ObjectMapper MAPPER = new ObjectMapper()
            .enable(SerializationFeature.INDENT_OUTPUT);

    /**
     * Builds a SCIM 2.0 compliant PATCH body for custom attributes.
     */
    public static String buildPatchBody(Map<String, String> customAttributes) throws Exception {
        List<Map<String, Object>> operations = new java.util.ArrayList<>();
        
        for (Map.Entry<String, String> entry : customAttributes.entrySet()) {
            Map<String, Object> op = new java.util.HashMap<>();
            op.put("op", "replace");
            // SCIM path syntax requires escaped quotes for attribute keys
            op.put("path", "customAttributes[\"" + entry.getKey() + "\"]");
            op.put("value", entry.getValue());
            operations.add(op);
        }

        Map<String, Object> payload = new java.util.HashMap<>();
        payload.put("Operations", operations);
        return MAPPER.writeValueAsString(payload);
    }
}

Required OAuth Scope: scim:users:write
Example Request Payload:

{
  "Operations": [
    {
      "op": "replace",
      "path": "customAttributes[\"department\"]",
      "value": "Engineering"
    },
    {
      "op": "replace",
      "path": "customAttributes[\"costCenter\"]",
      "value": "CC-4092"
    }
  ]
}

Step 3: Execute Batch Updates with Concurrency and Retry Logic

Bulk operations require careful concurrency management to avoid hitting Genesys Cloud rate limits (HTTP 429). The following implementation processes users in chunks, submits them to a thread pool, and implements exponential backoff when a 429 response is received. It also handles transient 5xx errors and validates 200/204 responses.

import java.net.URI;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.time.Duration;
import java.util.List;
import java.util.concurrent.*;
import java.util.logging.Level;
import java.util.logging.Logger;

public class ScimBatchUpdater {
    private static final Logger LOGGER = Logger.getLogger(ScimBatchUpdater.class.getName());
    private static final String BASE_URL = "https://api.mypurecloud.com/api/v2/scim/Users/";
    private static final int MAX_CONCURRENCY = 10;
    private static final int BATCH_SIZE = 50;
    private static final int MAX_RETRIES = 3;
    
    private final HttpClient httpClient;
    private final AuthManager authManager;

    public ScimBatchUpdater(HttpClient httpClient, AuthManager authManager) {
        this.httpClient = httpClient;
        this.authManager = authManager;
    }

    public void updateUsersInBatches(List<String> userIds, Map<String, String> attributes) throws Exception {
        ExecutorService executor = Executors.newFixedThreadPool(MAX_CONCURRENCY);
        Semaphore semaphore = new Semaphore(MAX_CONCURRENCY);
        List<Future<?>> futures = new java.util.ArrayList<>();

        for (int i = 0; i < userIds.size(); i += BATCH_SIZE) {
            List<String> batch = userIds.subList(i, Math.min(i + BATCH_SIZE, userIds.size()));
            for (String userId : batch) {
                Future<?> future = executor.submit(() -> {
                    try {
                        semaphore.acquire();
                        executePatchWithRetry(userId, attributes);
                    } catch (Exception e) {
                        LOGGER.log(Level.SEVERE, "Failed to update user " + userId, e);
                    } finally {
                        semaphore.release();
                    }
                });
                futures.add(future);
            }
        }

        // Wait for all batches to complete
        for (Future<?> f : futures) {
            f.get();
        }
        executor.shutdown();
    }

    private void executePatchWithRetry(String userId, Map<String, String> attributes) throws Exception {
        Exception lastException = null;
        for (int attempt = 0; attempt <= MAX_RETRIES; attempt++) {
            try {
                String token = authManager.getAccessToken();
                String payload = ScimPayloadBuilder.buildPatchBody(attributes);
                
                HttpRequest request = HttpRequest.newBuilder()
                        .uri(URI.create(BASE_URL + userId))
                        .header("Authorization", "Bearer " + token)
                        .header("Content-Type", "application/json")
                        .header("Accept", "application/json")
                        .PATCH(HttpRequest.BodyPublishers.ofString(payload))
                        .timeout(Duration.ofSeconds(30))
                        .build();

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

                if (statusCode == 200 || statusCode == 204) {
                    return; // Success
                } else if (statusCode == 429) {
                    // Rate limited: exponential backoff
                    long waitTime = 1000L * (long) Math.pow(2, attempt);
                    LOGGER.info("Rate limited (429). Retrying in " + waitTime + "ms");
                    Thread.sleep(waitTime);
                    continue;
                } else if (statusCode >= 500) {
                    // Server error: retry
                    LOGGER.warning("Server error (" + statusCode + ") for user " + userId + ". Retrying.");
                    Thread.sleep(500);
                    continue;
                } else {
                    // Client error (400, 403, etc.): do not retry
                    throw new RuntimeException("SCIM PATCH failed with status " + statusCode + ": " + response.body());
                }
            } catch (InterruptedException e) {
                Thread.currentThread().interrupt();
                throw e;
            } catch (Exception e) {
                lastException = e;
                if (attempt < MAX_RETRIES) {
                    Thread.sleep(1000);
                }
            }
        }
        throw new RuntimeException("Max retries exceeded for user " + userId, lastException);
    }
}

Expected Response (204 No Content):
SCIM 2.0 PATCH returns 204 on success with an empty body.
Expected Response (400 Bad Request):

{
  "errors": [
    {
      "detail": "Invalid SCIM patch operation: path 'customAttributes[\"invalid\"]' does not exist.",
      "status": "400"
    }
  ]
}

Complete Working Example

The following class ties authentication, connection pooling, and batch execution into a single runnable module. Replace the placeholder environment variables with your Genesys Cloud OAuth client credentials.

import java.util.List;
import java.util.Map;
import java.util.logging.Logger;

public class GenesysScimBulkUpdater {
    private static final Logger LOGGER = Logger.getLogger(GenesysScimBulkUpdater.class.getName());

    public static void main(String[] args) {
        try {
            // 1. Initialize components
            AuthManager authManager = new AuthManager();
            HttpClient httpClient = ScimHttpClientFactory.createPooledClient();
            ScimBatchUpdater updater = new ScimBatchUpdater(httpClient, authManager);

            // 2. Define target users and attributes
            List<String> userIds = List.of(
                "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
                "b2c3d4e5-f6a7-8901-bcde-f12345678901",
                "c3d4e5f6-a7b8-9012-cdef-123456789012"
            );

            Map<String, String> customAttributes = Map.of(
                "employeeId", "EMP-99201",
                "teamCode", "ALPHA",
                "shiftGroup", "US-CENTRAL"
            );

            LOGGER.info("Starting bulk SCIM update for " + userIds.size() + " users...");
            long start = System.currentTimeMillis();

            // 3. Execute batch operation
            updater.updateUsersInBatches(userIds, customAttributes);

            long duration = System.currentTimeMillis() - start;
            LOGGER.info("Bulk update completed successfully in " + duration + "ms");
        } catch (Exception e) {
            LOGGER.severe("Bulk update failed: " + e.getMessage());
            e.printStackTrace();
            System.exit(1);
        }
    }
}

Common Errors & Debugging

Error: HTTP 401 Unauthorized

• What causes it: The OAuth token is expired, malformed, or the client credentials are incorrect.
• How to fix it: Verify the GENESYS_CLIENT_ID and GENESYS_CLIENT_SECRET environment variables. Ensure the token manager refreshes the token before expiration. Check that the Authorization: Bearer <token> header is correctly formatted without extra spaces.
• Code showing the fix: The AuthManager class includes a time-based expiry check and double-checked locking to force a refresh when the token is older than expires_in - 60 seconds.

Error: HTTP 403 Forbidden

• What causes it: The OAuth token lacks the scim:users:write scope, or the client application is not authorized to modify users in the target organization.
• How to fix it: Navigate to the Genesys Cloud admin console, open the OAuth client configuration, and add scim:users:write to the allowed scopes. Regenerate the token after saving.
• Code showing the fix: The token request explicitly includes &scope=scim:users:write in the body. If the 403 persists, verify the client application type is set to Confidential.

Error: HTTP 400 Bad Request (SCIM Path Syntax)

• What causes it: The path parameter in the Operations array does not match Genesys Cloud SCIM syntax. Missing quotes around the attribute key or incorrect bracket placement triggers a 400.
• How to fix it: Use the exact format customAttributes[\"keyName\"]. The key must exactly match the custom attribute definition in Genesys Cloud, including case sensitivity.
• Code showing the fix: The ScimPayloadBuilder.buildPatchBody method constructs the path string with escaped double quotes: "customAttributes[\"" + entry.getKey() + "\"]".

Error: HTTP 429 Too Many Requests

• What causes it: The concurrent request rate exceeds the Genesys Cloud API throttle limits for SCIM operations.
• How to fix it: Reduce the MAX_CONCURRENCY and BATCH_SIZE constants. The retry loop implements exponential backoff (1000 * 2^attempt milliseconds) to automatically pause and retry when throttled.
• Code showing the fix: The executePatchWithRetry method catches 429 status codes, logs the throttle event, sleeps for the calculated backoff duration, and retries the request without failing the batch.

Official References

• Genesys Cloud SCIM 2.0 PATCH Users API Documentation
• OAuth 2.0 Client Credentials Flow
• java.net.http.HttpClient JavaDoc
• SCIM 2.0 Patch Operation Specification