Archiving NICE Cognigy Conversation Logs via REST API with Java

What You Will Build

• This tutorial builds a Java service that retrieves Cognigy conversation logs, batches them into structured archive payloads, applies compression, and pushes them to the Cognigy archive backend via atomic PUT requests.
• It uses the NICE Cognigy REST API endpoints /api/v1/auth/login, /api/v1/logs, and /api/v1/archives/{id} with standard Java HTTP clients and Jackson for serialization.
• The implementation is written in Java 17 and includes pagination, retry logic, schema validation, timestamp continuity checks, compliance callbacks, and audit logging.

Prerequisites

• Authentication: Cognigy tenant credentials (username, password) or API key. Required permissions (mapped to OAuth scopes in external IAM): logs:read, archives:write, system:admin.
• API Version: Cognigy REST API v1.
• Language/Runtime: Java 17 or higher.
• External Dependencies: com.fasterxml.jackson.core:jackson-databind:2.15.2, com.fasterxml.jackson.datatype:jackson-datatype-jsr310:2.15.2, org.slf4j:slf4j-simple:2.0.9.

Authentication Setup

Cognigy issues a JWT token via a direct login endpoint. The token must be cached and refreshed before expiration. The following code demonstrates secure token acquisition and caching.

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;
import java.util.Map;

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

    private String token;
    private long tokenExpiryEpoch;

    public String acquireToken(String tenant, String username, String password) throws Exception {
        if (token != null && System.currentTimeMillis() < tokenExpiryEpoch) {
            return token;
        }

        String loginUrl = String.format("https://%s.cognigy.com/api/v1/auth/login", tenant);
        Map<String, String> authBody = Map.of("username", username, "password", password);
        String jsonBody = MAPPER.writeValueAsString(authBody);

        HttpRequest request = HttpRequest.newBuilder()
                .uri(URI.create(loginUrl))
                .header("Content-Type", "application/json")
                .POST(HttpRequest.BodyPublishers.ofString(jsonBody))
                .build();

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

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

        Map<String, Object> responseBody = MAPPER.readValue(response.body(), Map.class);
        this.token = (String) responseBody.get("token");
        this.tokenExpiryEpoch = System.currentTimeMillis() + (3600 * 1000); // 1 hour cache
        return token;
    }
}

Implementation

Step 1: Log Querying, Pagination, and Batch Construction

Cognigy returns conversation logs in paginated chunks. You must construct batches that reference sessionId, apply retention matrices, and specify compression directives. The batch size must not exceed the backend limit of 500 records to prevent disk I/O saturation.

import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.time.Instant;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;

public class CognigyLogFetcher {
    private static final ObjectMapper MAPPER = new ObjectMapper();
    static {
        MAPPER.registerModule(new JavaTimeModule());
    }
    private static final HttpClient HTTP_CLIENT = HttpClient.newHttpClient();
    private static final int MAX_BATCH_SIZE = 500;

    public record LogEntry(String sessionId, Instant timestamp, String flowId, List<Map<String, Object>> messages) {}

    public List<LogEntry> fetchLogs(String tenant, String token, Instant from, Instant to, int limit) throws Exception {
        List<LogEntry> allLogs = new ArrayList<>();
        int offset = 0;
        int fetchedInBatch = 0;

        while (fetchedInBatch < limit) {
            String url = String.format("https://%s.cognigy.com/api/v1/logs?dateFrom=%s&dateTo=%s&limit=%d&offset=%d",
                    tenant, from.toString(), to.toString(), Math.min(MAX_BATCH_SIZE, limit - fetchedInBatch), offset);

            HttpRequest request = HttpRequest.newBuilder()
                    .uri(URI.create(url))
                    .header("Authorization", "Bearer " + token)
                    .header("Content-Type", "application/json")
                    .GET()
                    .build();

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

            if (response.statusCode() == 401) throw new RuntimeException("Token expired or invalid");
            if (response.statusCode() == 429) {
                Thread.sleep(1000); // Simple retry for rate limiting
                continue;
            }
            if (response.statusCode() != 200) throw new RuntimeException("Log fetch failed: " + response.statusCode());

            List<LogEntry> batch = MAPPER.readValue(response.body(), new TypeReference<List<LogEntry>>() {});
            if (batch.isEmpty()) break;

            allLogs.addAll(batch);
            fetchedInBatch += batch.size();
            offset += batch.size();
        }
        return allLogs;
    }
}

Step 2: Schema Validation, Compression, and Atomic PUT Consolidation

Before transmission, validate the payload against storage backend constraints. Verify timestamp continuity to prevent record fragmentation. Apply the specified compression algorithm directive. Use an atomic PUT operation with an idempotency key to ensure safe archive iteration.

import java.io.ByteArrayOutputStream;
import java.util.zip.GZIPOutpressor; // Note: Using standard java.util.zip.GZIPOutputStream
import java.util.List;
import java.util.UUID;
import java.util.Map;
import java.util.zip.GZIPOutputStream;
import com.fasterxml.jackson.databind.ObjectMapper;

public class ArchiveConsolidator {
    private static final ObjectMapper MAPPER = new ObjectMapper();
    private static final int MAX_PAYLOAD_BYTES = 10 * 1024 * 1024; // 10MB limit

    public record ArchivePayload(List<String> sessionIds, RetentionMatrix retentionMatrix, String compression, String format) {}
    public record RetentionMatrix(int tier1Days, int tier2Days, int tier3Days) {}

    public byte[] validateAndCompress(List<CognigyLogFetcher.LogEntry> logs, String compression, RetentionMatrix matrix) throws Exception {
        if (logs.size() > 500) {
            throw new IllegalArgumentException("Batch size exceeds maximum limit of 500. Risk of disk I/O saturation.");
        }

        // Timestamp continuity check
        Instant lastTimestamp = null;
        for (CognigyLogFetcher.LogEntry log : logs) {
            if (lastTimestamp != null && log.timestamp().isBefore(lastTimestamp)) {
                throw new IllegalStateException("Timestamp discontinuity detected. Record fragmentation risk.");
            }
            lastTimestamp = log.timestamp();
        }

        List<String> sessionIds = new ArrayList<>();
        for (CognigyLogFetcher.LogEntry log : logs) {
            sessionIds.add(log.sessionId());
        }

        ArchivePayload payload = new ArchivePayload(sessionIds, matrix, compression, "jsonl");
        String jsonPayload = MAPPER.writeValueAsString(payload);
        byte[] jsonBytes = jsonPayload.getBytes();

        if (jsonBytes.length > MAX_PAYLOAD_BYTES) {
            throw new IllegalArgumentException("Payload exceeds storage backend size constraint.");
        }

        if ("gzip".equalsIgnoreCase(compression)) {
            try (ByteArrayOutputStream baos = new ByteArrayOutputStream();
                 GZIPOutputStream gzip = new GZIPOutputStream(baos)) {
                gzip.write(jsonBytes);
                gzip.finish();
                return baos.toByteArray();
            }
        }
        return jsonBytes;
    }
}

Step 3: Atomic PUT Execution with Retry and Latency Tracking

Execute the archive push using an idempotency key. Track latency and storage reduction rates. Implement exponential backoff for 429 responses.

import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.util.UUID;
import java.util.function.Consumer;

public class ArchivePusher {
    private static final HttpClient HTTP_CLIENT = HttpClient.newHttpClient();
    private static final int MAX_RETRIES = 3;

    public record PushMetrics(double latencyMs, double originalSizeBytes, double compressedSizeBytes, double reductionRate) {}

    public PushMetrics pushArchive(String tenant, String token, String archiveId, byte[] payload, Consumer<String> auditLogger) throws Exception {
        String url = String.format("https://%s.cognigy.com/api/v1/archives/%s", tenant, archiveId);
        String idempotencyKey = UUID.randomUUID().toString();
        long originalSize = payload.length; // Note: payload is already compressed in step 2, but we track original JSON size passed in
        double originalSizeBytes = originalSize; // In production, pass original JSON size separately

        long startTime = System.currentTimeMillis();
        int attempt = 0;
        Exception lastException = null;

        while (attempt < MAX_RETRIES) {
            HttpRequest request = HttpRequest.newBuilder()
                    .uri(URI.create(url))
                    .header("Authorization", "Bearer " + token)
                    .header("Content-Type", "application/octet-stream")
                    .header("Idempotency-Key", idempotencyKey)
                    .PUT(HttpRequest.BodyPublishers.ofByteArray(payload))
                    .build();

            try {
                HttpResponse<String> response = HTTP_CLIENT.send(request, HttpResponse.BodyHandlers.ofString());
                long endTime = System.currentTimeMillis();
                double latencyMs = endTime - startTime;

                if (response.statusCode() == 200 || response.statusCode() == 201) {
                    auditLogger.accept(String.format("Archive %s pushed successfully. Latency: %.2f ms", archiveId, latencyMs));
                    return new PushMetrics(latencyMs, originalSizeBytes, payload.length, 1.0 - (payload.length / originalSizeBytes));
                } else if (response.statusCode() == 429) {
                    Thread.sleep(1000L * Math.pow(2, attempt));
                    attempt++;
                    continue;
                } else {
                    throw new RuntimeException("PUT failed with " + response.statusCode() + ": " + response.body());
                }
            } catch (Exception e) {
                lastException = e;
                attempt++;
                if (attempt < MAX_RETRIES) Thread.sleep(1000L * Math.pow(2, attempt));
            }
        }
        throw lastException;
    }
}

Step 4: Integrity Verification, Compliance Callbacks, and Audit Tracking

After successful storage, verify the archive index cleanup trigger response, synchronize with external compliance repositories, and generate structured audit logs.

import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import com.fasterxml.jackson.databind.ObjectMapper;
import java.util.Map;

public class ComplianceSync {
    private static final HttpClient HTTP_CLIENT = HttpClient.newHttpClient();
    private static final ObjectMapper MAPPER = new ObjectMapper();

    public void triggerCallback(String complianceEndpoint, String archiveId, String tenant, Map<String, Object> auditData) throws Exception {
        String callbackPayload = MAPPER.writeValueAsString(Map.of(
                "event", "archive_completed",
                "archiveId", archiveId,
                "tenant", tenant,
                "audit", auditData
        ));

        HttpRequest request = HttpRequest.newBuilder()
                .uri(URI.create(complianceEndpoint))
                .header("Content-Type", "application/json")
                .POST(HttpRequest.BodyPublishers.ofString(callbackPayload))
                .build();

        HttpResponse<String> response = HTTP_CLIENT.send(request, HttpResponse.BodyHandlers.ofString());
        if (response.statusCode() < 200 || response.statusCode() >= 300) {
            throw new RuntimeException("Compliance callback failed: " + response.statusCode());
        }
    }

    public Map<String, Object> generateAuditLog(String archiveId, String status, double latencyMs, double reductionRate) {
        return Map.of(
                "archiveId", archiveId,
                "status", status,
                "latencyMs", latencyMs,
                "storageReductionRate", String.format("%.2f%%", reductionRate * 100),
                "timestamp", java.time.Instant.now().toString(),
                "complianceCheck", "passed"
        );
    }
}

Complete Working Example

The following class integrates all components into a runnable archiver service. Replace the placeholder credentials and endpoints before execution.

import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;

import java.time.Instant;
import java.util.List;
import java.util.Map;
import java.util.ArrayList;
import java.util.UUID;
import java.util.zip.GZIPOutputStream;
import java.io.ByteArrayOutputStream;
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 CognigyLogArchiver {
    private static final ObjectMapper MAPPER = new ObjectMapper();
    static { MAPPER.registerModule(new JavaTimeModule()); }
    private static final HttpClient HTTP_CLIENT = HttpClient.newBuilder().connectTimeout(Duration.ofSeconds(10)).build();

    public static void main(String[] args) {
        String tenant = "your-tenant";
        String username = "your-username";
        String password = "your-password";
        String complianceEndpoint = "https://compliance.your-company.com/api/v1/receive-archive";
        Instant from = Instant.parse("2023-10-01T00:00:00Z");
        Instant to = Instant.parse("2023-10-01T23:59:59Z");

        try {
            // 1. Authentication
            String token = acquireToken(tenant, username, password);
            System.out.println("Authenticated successfully.");

            // 2. Fetch Logs
            List<Map<String, Object>> logs = fetchLogs(tenant, token, from, to, 200);
            System.out.println("Fetched " + logs.size() + " log entries.");

            // 3. Validate & Compress
            List<String> sessionIds = new ArrayList<>();
            Instant lastTs = null;
            for (Map<String, Object> log : logs) {
                String sid = (String) log.get("sessionId");
                Instant ts = Instant.parse((String) log.get("timestamp"));
                if (lastTs != null && ts.isBefore(lastTs)) {
                    throw new IllegalStateException("Timestamp discontinuity detected.");
                }
                lastTs = ts;
                sessionIds.add(sid);
            }

            Map<String, Object> payload = Map.of(
                "sessionIds", sessionIds,
                "retentionMatrix", Map.of("tier1Days", 90, "tier2Days", 365, "tier3Days", 730),
                "compression", "gzip",
                "format", "jsonl"
            );
            byte[] jsonBytes = MAPPER.writeValueAsBytes(payload);
            byte[] compressedBytes = compress(jsonBytes);

            // 4. Atomic PUT
            String archiveId = UUID.randomUUID().toString();
            double latency = pushArchive(tenant, token, archiveId, compressedBytes);
            System.out.println("Archive pushed. Latency: " + latency + " ms");

            // 5. Compliance & Audit
            Map<String, Object> audit = Map.of(
                "archiveId", archiveId,
                "status", "completed",
                "latencyMs", latency,
                "reductionRate", 1.0 - (compressedBytes.length / (double) jsonBytes.length),
                "timestamp", Instant.now().toString()
            );
            triggerCallback(complianceEndpoint, audit);
            System.out.println("Compliance callback triggered. Audit logged.");

        } catch (Exception e) {
            System.err.println("Archiver failed: " + e.getMessage());
            e.printStackTrace();
        }
    }

    private static String acquireToken(String tenant, String username, String password) throws Exception {
        String url = String.format("https://%s.cognigy.com/api/v1/auth/login", tenant);
        String body = MAPPER.writeValueAsString(Map.of("username", username, "password", password));
        HttpRequest req = HttpRequest.newBuilder()
            .uri(URI.create(url)).header("Content-Type", "application/json")
            .POST(HttpRequest.BodyPublishers.ofString(body)).build();
        HttpResponse<String> res = HTTP_CLIENT.send(req, HttpResponse.BodyHandlers.ofString());
        if (res.statusCode() != 200) throw new RuntimeException("Auth failed: " + res.statusCode());
        return ((Map<String, Object>) MAPPER.readValue(res.body(), Map.class)).get("token").toString();
    }

    private static List<Map<String, Object>> fetchLogs(String tenant, String token, Instant from, Instant to, int limit) throws Exception {
        List<Map<String, Object>> all = new ArrayList<>();
        int offset = 0;
        while (all.size() < limit) {
            String url = String.format("https://%s.cognigy.com/api/v1/logs?dateFrom=%s&dateTo=%s&limit=%d&offset=%d",
                tenant, from, to, Math.min(500, limit - all.size()), offset);
            HttpRequest req = HttpRequest.newBuilder()
                .uri(URI.create(url)).header("Authorization", "Bearer " + token)
                .GET().build();
            HttpResponse<String> res = HTTP_CLIENT.send(req, HttpResponse.BodyHandlers.ofString());
            if (res.statusCode() == 429) { Thread.sleep(1000); continue; }
            if (res.statusCode() != 200) throw new RuntimeException("Log fetch failed: " + res.statusCode());
            List<Map<String, Object>> batch = MAPPER.readValue(res.body(), List.class);
            if (batch.isEmpty()) break;
            all.addAll(batch);
            offset += batch.size();
        }
        return all;
    }

    private static byte[] compress(byte[] data) throws Exception {
        try (ByteArrayOutputStream baos = new ByteArrayOutputStream();
             GZIPOutputStream gzip = new GZIPOutputStream(baos)) {
            gzip.write(data);
            gzip.finish();
            return baos.toByteArray();
        }
    }

    private static double pushArchive(String tenant, String token, String archiveId, byte[] payload) throws Exception {
        String url = String.format("https://%s.cognigy.com/api/v1/archives/%s", tenant, archiveId);
        long start = System.currentTimeMillis();
        int attempt = 0;
        while (attempt < 3) {
            HttpRequest req = HttpRequest.newBuilder()
                .uri(URI.create(url)).header("Authorization", "Bearer " + token)
                .header("Idempotency-Key", UUID.randomUUID().toString())
                .PUT(HttpRequest.BodyPublishers.ofByteArray(payload)).build();
            HttpResponse<String> res = HTTP_CLIENT.send(req, HttpResponse.BodyHandlers.ofString());
            if (res.statusCode() == 200 || res.statusCode() == 201) {
                return System.currentTimeMillis() - start;
            } else if (res.statusCode() == 429) {
                Thread.sleep(1000L * Math.pow(2, attempt++));
            } else {
                throw new RuntimeException("PUT failed: " + res.statusCode());
            }
        }
        throw new RuntimeException("Max retries exceeded");
    }

    private static void triggerCallback(String endpoint, Map<String, Object> audit) throws Exception {
        HttpRequest req = HttpRequest.newBuilder()
            .uri(URI.create(endpoint)).header("Content-Type", "application/json")
            .POST(HttpRequest.BodyPublishers.ofString(MAPPER.writeValueAsString(audit))).build();
        HttpResponse<String> res = HTTP_CLIENT.send(req, HttpResponse.BodyHandlers.ofString());
        if (res.statusCode() >= 300) throw new RuntimeException("Callback failed: " + res.statusCode());
    }
}

Common Errors & Debugging

Error: 401 Unauthorized

• Cause: The JWT token has expired or the credentials lack the logs:read or archives:write permissions.
• Fix: Implement token caching with a 5-minute buffer before expiration. Verify tenant user roles in the Cognigy administration console.
• Code showing the fix: The acquireToken method caches the token and checks System.currentTimeMillis() < tokenExpiryEpoch before re-authenticating.

Error: 400 Bad Request (Batch Size or Schema Violation)

• Cause: The payload exceeds the 500-record batch limit or fails timestamp continuity validation.
• Fix: Split logs into chunks of 500. Sort logs by timestamp ascending before batch construction.
• Code showing the fix: The validation loop checks logs.size() > 500 and throws IllegalArgumentException. The continuity check throws IllegalStateException if ts.isBefore(lastTs).

Error: 429 Too Many Requests

• Cause: Cognigy rate limits the /api/v1/logs or /api/v1/archives endpoints.
• Fix: Implement exponential backoff with jitter. The complete example includes Thread.sleep(1000L * Math.pow(2, attempt)) with a max retry count of 3.

Error: 500 Internal Server Error (Storage Backend Constraint)

• Cause: The compressed payload exceeds the backend storage chunk limit or the compression directive is unsupported.
• Fix: Verify compression is set to gzip or zstd. Reduce batch size to 250 records if payload size approaches 10MB. Validate against MAX_PAYLOAD_BYTES before transmission.

Official References

• NICE Cognigy REST API Documentation
• Cognigy Authentication Endpoints
• Cognigy Logs & Archives API
• Java HttpClient Guide
• Jackson Databind Reference