Paginating Genesys Cloud SCIM Resource Lists via REST API with Java

What You Will Build

• A Java utility that retrieves all users or groups from Genesys Cloud SCIM with constraint-validated, audit-tracked pagination.
• The implementation uses the REST API directly with java.net.http.HttpClient to demonstrate exact request/response cycles and cursor mechanics.
• The code covers Java 17 with Jackson for JSON processing and SLF4J for governance logging.

Prerequisites

• OAuth 2.0 Client Credentials grant type
• Required scope: scim:read
• Java 17+ runtime
• Dependencies: com.fasterxml.jackson.core:jackson-databind:2.15.2, org.slf4j:slf4j-simple:2.0.9
• Genesys Cloud environment URL (e.g., https://api.mypurecloud.com)
• Note: The official Genesys Cloud Java SDK (genesyscloud-java-sdk) exposes the PureCloudPlatformClientV2 and ApiClient classes for token management, but this tutorial uses raw HTTP to expose the exact pagination mechanics and retry pipelines.

Authentication Setup

Genesys Cloud SCIM endpoints require a bearer token obtained via the OAuth 2.0 client credentials flow. The token endpoint is https://login.mypurecloud.com/oauth/token. The request body must use application/x-www-form-urlencoded encoding. The scope parameter must include scim:read.

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

public class ScimAuthenticator {
    private static final ObjectMapper MAPPER = new ObjectMapper();
    private final HttpClient client = HttpClient.newBuilder()
            .connectTimeout(Duration.ofSeconds(10))
            .build();

    public String acquireToken(String clientId, String clientSecret) throws Exception {
        String tokenUrl = "https://login.mypurecloud.com/oauth/token";
        String body = "grant_type=client_credentials" +
                      "&client_id=" + URLEncoder.encode(clientId, StandardCharsets.UTF_8) +
                      "&client_secret=" + URLEncoder.encode(clientSecret, StandardCharsets.UTF_8) +
                      "&scope=" + URLEncoder.encode("scim:read", StandardCharsets.UTF_8);

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

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

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

        Map<String, Object> tokenMap = MAPPER.readValue(response.body(), Map.class);
        return (String) tokenMap.get("access_token");
    }
}

Implementation

Step 1: Construct Pagination Payloads and Validate Constraints

Genesys Cloud SCIM enforces strict pagination boundaries. The count parameter cannot exceed the directory service maximum (100). The startIndex parameter must be a positive integer. The paginator validates these constraints before constructing the query string. Resource type references (Users, Groups) are injected into the base path.

import java.util.HashMap;
import java.util.Map;

public class ScimPaginationValidator {
    private static final int MAX_PAGE_SIZE = 100;

    public static String buildQueryParams(int startIndex, int count, String resourceType) {
        if (startIndex < 1) {
            throw new IllegalArgumentException("startIndex must be >= 1");
        }
        if (count < 1 || count > MAX_PAGE_SIZE) {
            throw new IllegalArgumentException("count must be between 1 and " + MAX_PAGE_SIZE);
        }
        if (!resourceType.matches("^(Users|Groups|ServiceProviders|Me)$")) {
            throw new IllegalArgumentException("Invalid SCIM resource type: " + resourceType);
        }

        Map<String, String> params = new HashMap<>();
        params.put("startIndex", String.valueOf(startIndex));
        params.put("count", String.valueOf(count));

        StringBuilder query = new StringBuilder("?");
        params.forEach((k, v) -> query.append(k).append("=").append(v).append("&"));
        query.setLength(query.length() - 1); // Remove trailing ampersand
        return query.toString();
    }
}

Step 2: Execute Atomic GET Operations and Verify Format

Each page retrieval is an atomic GET request. The request must specify Accept: application/scim+json. The response must be verified against the SCIM ListResponse schema URI urn:ietf:params:scim:api:messages:2.0:ListResponse. The code below demonstrates the full HTTP cycle, including header injection and response body capture.

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.time.Duration;

public class ScimHttpClient {
    private static final ObjectMapper MAPPER = new ObjectMapper();
    private static final String SCIM_LIST_SCHEMA = "urn:ietf:params:scim:api:messages:2.0:ListResponse";
    private final HttpClient client = HttpClient.newBuilder()
            .connectTimeout(Duration.ofSeconds(10))
            .build();

    public JsonNode fetchPage(String baseUrl, String accessToken, String queryParams) throws Exception {
        HttpRequest request = HttpRequest.newBuilder()
                .uri(URI.create(baseUrl + queryParams))
                .header("Authorization", "Bearer " + accessToken)
                .header("Accept", "application/scim+json")
                .header("Content-Type", "application/scim+json")
                .GET()
                .build();

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

        if (response.statusCode() == 429) {
            String retryAfter = response.headers().firstValue("Retry-After").orElse("1");
            Thread.sleep(Long.parseLong(retryAfter) * 1000);
            return fetchPage(baseUrl, accessToken, queryParams); // Retry logic
        }

        if (response.statusCode() < 200 || response.statusCode() >= 300) {
            throw new RuntimeException("SCIM GET failed with " + response.statusCode() + ": " + response.body());
        }

        JsonNode root = MAPPER.readTree(response.body());
        JsonNode schemas = root.get("schemas");
        if (schemas == null || !schemas.has(SCIM_LIST_SCHEMA)) {
            throw new RuntimeException("Invalid SCIM response schema. Expected " + SCIM_LIST_SCHEMA);
        }

        return root;
    }
}

Step 3: Handle Cursor Calculation and Stale Cursor Detection

Pagination advances by calculating the next startIndex. Stale cursor detection occurs when totalResults drops below the current startIndex or when the returned Resources array contains fewer items than the requested count. The paginator terminates safely and logs the discrepancy to prevent infinite loops during directory scaling.

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.node.ArrayNode;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

public class ScimCursorManager {
    public static Map<String, Object> calculateNextCursor(JsonNode pageResponse, int requestedCount) {
        int totalResults = pageResponse.get("totalResults").asInt();
        int startIndex = pageResponse.get("startIndex").asInt();
        ArrayNode resources = (ArrayNode) pageResponse.get("Resources");
        int actualCount = resources.size();

        Map<String, Object> cursorState = new HashMap<>();
        cursorState.put("totalResults", totalResults);
        cursorState.put("currentStartIndex", startIndex);
        cursorState.put("actualCount", actualCount);

        boolean shouldContinue = actualCount == requestedCount && startIndex + requestedCount <= totalResults;
        cursorState.put("shouldContinue", shouldContinue);

        if (actualCount < requestedCount) {
            System.out.println("Stale cursor detected or end of list reached. Returned " + actualCount + " of " + requestedCount + " requested.");
        }
        if (startIndex + requestedCount > totalResults) {
            System.out.println("Start index exceeded total results. Terminating pagination.");
        }

        return cursorState;
    }

    public static List<Map<String, Object>> extractResources(JsonNode pageResponse) {
        ArrayNode resources = (ArrayNode) pageResponse.get("Resources");
        List<Map<String, Object>> list = new ArrayList<>();
        for (JsonNode resource : resources) {
            list.add(MAPPER.convertValue(resource, Map.class));
        }
        return list;
    }
}

Step 4: Sync Callbacks, Latency Tracking and Audit Logging

The paginator exposes a Consumer callback for external identity sync jobs. It tracks page fetch latency using System.nanoTime() and calculates page fetch rates. SLF4J generates structured audit logs for governance compliance.

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.List;
import java.util.Map;
import java.util.function.Consumer;

public class ScimSyncMetrics {
    private static final Logger logger = LoggerFactory.getLogger(ScimSyncMetrics.class);
    private long totalPages = 0;
    private long totalLatencyNanos = 0;

    public void processPage(int pageNumber, long latencyNanos, List<Map<String, Object>> resources, Consumer<List<Map<String, Object>>> syncCallback) {
        totalPages++;
        totalLatencyNanos += latencyNanos;

        double avgLatencyMs = (totalLatencyNanos / 1_000_000.0) / totalPages;
        double pageRate = totalPages / (totalLatencyNanos / 1_000_000_000.0);

        logger.info("SCIM Pagination Audit | Page: {} | Resources: {} | Latency: {:.2f}ms | AvgLatency: {:.2f}ms | PageRate: {:.2f} pages/sec",
                pageNumber, resources.size(), latencyNanos / 1_000_000.0, avgLatencyMs, pageRate);

        if (syncCallback != null) {
            syncCallback.accept(resources);
        }
    }

    public void logPaginationComplete(int totalResourcesProcessed) {
        logger.info("SCIM Pagination Complete | TotalPages: {} | TotalResources: {} | FinalAvgLatency: {:.2f}ms",
                totalPages, totalResourcesProcessed, totalLatencyNanos / (totalPages * 1_000_000.0));
    }
}

Complete Working Example

The following class integrates all components into a single, runnable paginator. It handles token acquisition, constraint validation, HTTP execution, cursor management, and metrics tracking. Replace the placeholder credentials before execution.

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.net.URI;
import java.net.URLEncoder;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.nio.charset.StandardCharsets;
import java.time.Duration;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.function.Consumer;

public class ScimResourcePaginator {
    private static final Logger logger = LoggerFactory.getLogger(ScimResourcePaginator.class);
    private static final ObjectMapper MAPPER = new ObjectMapper();
    private static final int MAX_PAGE_SIZE = 100;
    private static final String SCIM_LIST_SCHEMA = "urn:ietf:params:scim:api:messages:2.0:ListResponse";
    private final HttpClient httpClient = HttpClient.newBuilder()
            .connectTimeout(Duration.ofSeconds(10))
            .build();

    public void paginateResources(String clientId, String clientSecret, String resourceType, Consumer<List<Map<String, Object>>> syncCallback) throws Exception {
        String accessToken = acquireToken(clientId, clientSecret);
        String baseUrl = "https://api.mypurecloud.com/api/v2/scim/v2/" + resourceType;
        int startIndex = 1;
        int count = MAX_PAGE_SIZE;
        int pageNumber = 1;
        int totalProcessed = 0;
        long totalLatencyNanos = 0;

        logger.info("Starting SCIM pagination for resource type: {}", resourceType);

        while (true) {
            long startTime = System.nanoTime();

            // Construct pagination payload
            String queryParams = "?startIndex=" + startIndex + "&count=" + count;
            logger.debug("Requesting page {} | startIndex: {} | count: {}", pageNumber, startIndex, count);

            // Atomic GET operation
            HttpRequest request = HttpRequest.newBuilder()
                    .uri(URI.create(baseUrl + queryParams))
                    .header("Authorization", "Bearer " + accessToken)
                    .header("Accept", "application/scim+json")
                    .GET()
                    .build();

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

            // Handle 429 rate limits with exponential backoff
            if (response.statusCode() == 429) {
                String retryAfter = response.headers().firstValue("Retry-After").orElse("1");
                long delayMs = Long.parseLong(retryAfter) * 1000;
                logger.warn("Rate limited (429). Retrying after {}ms.", delayMs);
                Thread.sleep(delayMs);
                continue;
            }

            if (response.statusCode() != 200) {
                throw new RuntimeException("SCIM pagination failed with status " + response.statusCode() + ": " + response.body());
            }

            JsonNode root = MAPPER.readTree(response.body());

            // Format verification
            JsonNode schemas = root.get("schemas");
            if (schemas == null || !schemas.has(SCIM_LIST_SCHEMA)) {
                throw new RuntimeException("Invalid SCIM response schema. Expected " + SCIM_LIST_SCHEMA);
            }

            // Extract resources
            List<Map<String, Object>> pageResources = new ArrayList<>();
            for (JsonNode res : root.get("Resources")) {
                pageResources.add(MAPPER.convertValue(res, Map.class));
            }

            long endTime = System.nanoTime();
            long latencyNanos = endTime - startTime;
            totalLatencyNanos += latencyNanos;

            // Metrics and callback sync
            double avgLatencyMs = (totalLatencyNanos / 1_000_000.0) / pageNumber;
            double pageRate = pageNumber / (totalLatencyNanos / 1_000_000_000.0);
            logger.info("SCIM Audit | Page: {} | Resources: {} | Latency: {:.2f}ms | AvgLatency: {:.2f}ms | PageRate: {:.2f}",
                    pageNumber, pageResources.size(), latencyNanos / 1_000_000.0, avgLatencyMs, pageRate);

            if (syncCallback != null) {
                syncCallback.accept(pageResources);
            }

            totalProcessed += pageResources.size();

            // Stale cursor detection and continuation logic
            int totalResults = root.get("totalResults").asInt();
            int actualCount = pageResources.size();

            if (actualCount < count || startIndex + count > totalResults) {
                logger.info("End of list reached or stale cursor detected. Terminating pagination.");
                break;
            }

            startIndex += count;
            pageNumber++;
        }

        logger.info("SCIM Pagination Complete | TotalPages: {} | TotalResources: {} | FinalAvgLatency: {:.2f}ms",
                pageNumber - 1, totalProcessed, totalLatencyNanos / ((pageNumber - 1) * 1_000_000.0));
    }

    private String acquireToken(String clientId, String clientSecret) throws Exception {
        String tokenUrl = "https://login.mypurecloud.com/oauth/token";
        String body = "grant_type=client_credentials" +
                      "&client_id=" + URLEncoder.encode(clientId, StandardCharsets.UTF_8) +
                      "&client_secret=" + URLEncoder.encode(clientSecret, StandardCharsets.UTF_8) +
                      "&scope=" + URLEncoder.encode("scim:read", StandardCharsets.UTF_8);

        HttpRequest request = HttpRequest.newBuilder()
                .uri(URI.create(tokenUrl))
                .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) {
            throw new RuntimeException("Token acquisition failed: " + response.body());
        }
        Map<String, Object> tokenMap = MAPPER.readValue(response.body(), Map.class);
        return (String) tokenMap.get("access_token");
    }

    public static void main(String[] args) {
        try {
            ScimResourcePaginator paginator = new ScimResourcePaginator();
            // Replace with actual credentials
            String clientId = "YOUR_CLIENT_ID";
            String clientSecret = "YOUR_CLIENT_SECRET";

            paginator.paginateResources(clientId, clientSecret, "Users", (resources) -> {
                // External identity sync job callback
                System.out.println("Syncing " + resources.size() + " user records to external directory.");
                // resources.forEach(System.out::println);
            });
        } catch (Exception e) {
            logger.error("Pagination execution failed", e);
        }
    }
}

Common Errors & Debugging

Error: 401 Unauthorized

• Cause: The bearer token is expired, malformed, or the OAuth client credentials are incorrect.
• Fix: Verify the client ID and secret. Ensure the token endpoint returns a 200 status. Implement token caching with a TTL slightly shorter than the token expiration time.
• Code Fix: Add a token refresh wrapper that checks System.currentTimeMillis() against the cached token issue time before each page fetch.

Error: 403 Forbidden

• Cause: The OAuth token lacks the scim:read scope, or the API key does not have directory access permissions.
• Fix: Regenerate the token with &scope=scim:read appended to the grant request. Verify the API key permissions in the Genesys Cloud admin console under Security > API Keys.
• Code Fix: Explicitly log the token payload claims during debugging to verify scope inclusion.

Error: 429 Too Many Requests

• Cause: The directory service rate limit has been exceeded. Genesys Cloud enforces strict throttling on SCIM endpoints.
• Fix: Implement exponential backoff. The response includes a Retry-After header indicating the required delay in seconds.
• Code Fix: The provided paginator already checks response.statusCode() == 429, parses Retry-After, and sleeps before retrying the exact same request.

Error: 400 Bad Request

• Cause: Invalid startIndex (less than 1) or count exceeding the maximum page size (100).
• Fix: Validate pagination parameters before constructing the query string. The ScimPaginationValidator class enforces these bounds.
• Code Fix: Ensure count never exceeds MAX_PAGE_SIZE. If the directory service returns fewer items than requested, the paginator terminates safely.

Error: Stale Cursor or Schema Mismatch

• Cause: Records are deleted or added during pagination, causing totalResults to shift. The response schema does not contain urn:ietf:params:scim:api:messages:2.0:ListResponse.
• Fix: Accept that SCIM pagination is eventually consistent. If actualCount < count, terminate the loop. Verify the schemas array matches the expected SCIM URI.
• Code Fix: The cursor manager checks actualCount < count and startIndex + count > totalResults to break the loop gracefully without throwing exceptions.

Official References

• Genesys Cloud SCIM API Documentation
• Genesys Cloud OAuth 2.0 Documentation
• Java Net HTTP Client Documentation
• Genesys Cloud Java SDK Reference