Replication

AEM Cloud Service Replication API

Programmatic content publishing and unpublishing using the official AEM Replication API.

When to Use This Skill

Use the Replication API for programmatic content distribution:

• Custom OSGi services that publish content
• Workflow process steps requiring activation
• Automated publishing pipelines
• Integration with external systems
• Bulk operations (with proper constraints)

For UI-based publishing, use Manage Publication or Quick Publish instead.

Official API Documentation

Javadoc: https://developer.adobe.com/experience-manager/reference-materials/cloud-service/javadoc/com/day/cq/replication/package-summary.html

Key Classes:

• com.day.cq.replication.Replicator - Main replication service
• com.day.cq.replication.ReplicationOptions - Configuration options
• com.day.cq.replication.ReplicationStatus - Publication status
• com.day.cq.replication.ReplicationActionType - Action types (ACTIVATE, DEACTIVATE, DELETE, TEST)

Basic Replication: Single Path

Example: Activate a Page

import com.day.cq.replication.Replicator;
import com.day.cq.replication.ReplicationActionType;
import com.day.cq.replication.ReplicationException;
import org.osgi.service.component.annotations.Component;
import org.osgi.service.component.annotations.Reference;
import javax.jcr.Session;

@Component(service = ContentPublisher.class)
public class ContentPublisher {
    
    @Reference
    private Replicator replicator;
    
    /**
     * Activate a single page to Publish tier
     */
    public void publishPage(Session session, String pagePath) 
            throws ReplicationException {
        
        replicator.replicate(
            session,
            ReplicationActionType.ACTIVATE,
            pagePath
        );
    }
    
    /**
     * Deactivate a page from Publish tier
     */
    public void unpublishPage(Session session, String pagePath) 
            throws ReplicationException {
        
        replicator.replicate(
            session,
            ReplicationActionType.DEACTIVATE,
            pagePath
        );
    }
    
    /**
     * Delete content from Publish tier
     */
    public void deleteFromPublish(Session session, String path) 
            throws ReplicationException {
        
        replicator.replicate(
            session,
            ReplicationActionType.DELETE,
            path
        );
    }
}

Bulk Replication: Multiple Paths

CONSTRAINTS (per official Javadoc):

• Recommended limit: 100 paths per call for a transactional guarantee
• Above 100 paths: the system automatically splits into multiple non-transactional chunks — no extra options needed
• Payload size: 10 MB maximum (excluding binaries)

Note: ReplicationOptions.setUseAtomicCalls() is @Deprecated and marked "no longer required" in the Cloud Service Javadoc. Do not call it; the system handles auto-bucketing automatically.

Example: Bulk Activation

public class BulkPublisher {
    
    @Reference
    private Replicator replicator;
    
    /**
     * Publish multiple pages.
     * ≤100 paths → replicated atomically (transactional guarantee).
     * >100 paths → system automatically splits into non-transactional chunks.
     */
    public void publishMultiplePages(Session session, String[] pagePaths) 
            throws ReplicationException {
        
        replicator.replicate(
            session,
            ReplicationActionType.ACTIVATE,
            pagePaths,
            null  // No options needed; system handles auto-bucketing above 100 paths
        );
    }
}

Best Practice: For large hierarchical content trees, use the Tree Activation workflow step instead of custom code.

Publishing to Preview Tier

The Preview tier requires explicit agent filtering.

Example: Publish to Preview

import com.day.cq.replication.Agent;
import com.day.cq.replication.AgentFilter;

public class PreviewPublisher {
    
    @Reference
    private Replicator replicator;
    
    /**
     * Publish to Preview tier only
     */
    public void publishToPreview(Session session, String pagePath) 
            throws ReplicationException {
        
        ReplicationOptions options = new ReplicationOptions();
        
        // Filter to target Preview agent only
        options.setFilter(new AgentFilter() {
            @Override
            public boolean isIncluded(Agent agent) {
                return "preview".equals(agent.getId());
            }
        });
        
        replicator.replicate(
            session,
            ReplicationActionType.ACTIVATE,
            pagePath,
            options
        );
    }
    
    /**
     * Publish to BOTH Preview and Publish tiers
     */
    public void publishToBothTiers(Session session, String pagePath) 
            throws ReplicationException {
        
        ReplicationOptions options = new ReplicationOptions();
        
        // Include both preview and publish agents
        options.setFilter(new AgentFilter() {
            @Override
            public boolean isIncluded(Agent agent) {
                String agentId = agent.getId();
                return "preview".equals(agentId) || "publish".equals(agentId);
            }
        });
        
        replicator.replicate(
            session,
            ReplicationActionType.ACTIVATE,
            pagePath,
            options
        );
    }
}

Note: Preview agent is disabled by default and must be configured in Cloud Manager.

Advanced Options: ReplicationOptions

Synchronous vs. Asynchronous Replication

public class SynchronousPublisher {
    
    @Reference
    private Replicator replicator;
    
    /**
     * Synchronous replication (wait for completion)
     */
    public void publishSynchronously(Session session, String pagePath) 
            throws ReplicationException {
        
        ReplicationOptions options = new ReplicationOptions();
        options.setSynchronous(true);  // Block until complete
        
        // Optional: Add listener for synchronous feedback
        options.setListener(new ReplicationListener() {
            @Override
            public void onStart(ReplicationAction action) {
                // Called when replication starts
            }
            
            @Override
            public void onMessage(ReplicationLog.Level level, String message) {
                // Called for progress updates
            }
            
            @Override
            public void onEnd(ReplicationAction action, ReplicationResult result) {
                // Called when replication completes
            }
            
            @Override
            public void onError(ReplicationAction action, Exception error) {
                // Called if replication fails
            }
        });
        
        replicator.replicate(
            session,
            ReplicationActionType.ACTIVATE,
            pagePath,
            options
        );
    }
}

Important: ReplicationListener only works with synchronous replication.

Suppress Status Updates

/**
 * Replicate without updating replication metadata properties
 */
public void replicateWithoutStatusUpdate(Session session, String path) 
        throws ReplicationException {
    
    ReplicationOptions options = new ReplicationOptions();
    options.setSuppressStatusUpdate(true);  // Don't update cq:lastReplicated, etc.
    
    replicator.replicate(
        session,
        ReplicationActionType.ACTIVATE,
        path,
        options
    );
}

Suppress Versioning

/**
 * Replicate without creating implicit versions
 */
public void replicateWithoutVersioning(Session session, String path) 
        throws ReplicationException {
    
    ReplicationOptions options = new ReplicationOptions();
    options.setSuppressVersions(true);  // Don't auto-version on replication
    
    replicator.replicate(
        session,
        ReplicationActionType.ACTIVATE,
        path,
        options
    );
}

Checking Replication Status

Example: Check if Page is Published

import com.day.cq.replication.ReplicationStatus;
import org.apache.sling.api.resource.Resource;

public class StatusChecker {
    
    @Reference
    private Replicator replicator;
    
    /**
     * Check if content is currently published
     */
    public boolean isPublished(Session session, String path) 
            throws ReplicationException {
        
        ReplicationStatus status = replicator.getReplicationStatus(session, path);
        
        if (status == null) {
            return false;  // No replication metadata
        }
        
        return status.isActivated();
    }
    
    /**
     * Get detailed replication information
     */
    public void printReplicationInfo(Session session, String path) 
            throws ReplicationException {
        
        ReplicationStatus status = replicator.getReplicationStatus(session, path);
        
        if (status != null) {
            System.out.println("Activated: " + status.isActivated());
            System.out.println("Deactivated: " + status.isDeactivated());
            System.out.println("Last Published: " + status.getLastPublished());
            System.out.println("Published By: " + status.getLastPublishedBy());
            System.out.println("Last Action: " + status.getLastReplicationAction());
            System.out.println("Pending: " + status.isPending());
        }
    }
    
    /**
     * Alternative: Adapt resource to ReplicationStatus
     */
    public boolean isPublished(Resource resource) {
        ReplicationStatus status = resource.adaptTo(ReplicationStatus.class);
        return status != null && status.isActivated();
    }
}

Batch Status Queries

Use ReplicationStatusProvider.getBatchReplicationStatus() when you need to check the publication state of multiple resources in a single call. It is more efficient than calling Replicator.getReplicationStatus() in a loop.

Javadoc: com.day.cq.replication.ReplicationStatusProvider

import com.day.cq.replication.ReplicationStatus;
import com.day.cq.replication.ReplicationStatusProvider;
import org.apache.sling.api.resource.Resource;
import org.apache.sling.api.resource.ResourceResolver;
import org.osgi.service.component.annotations.Component;
import org.osgi.service.component.annotations.Reference;

@Component(service = BatchStatusChecker.class)
public class BatchStatusChecker {

    @Reference
    private ReplicationStatusProvider replicationStatusProvider;

    /**
     * Returns a map of path → ReplicationStatus for all given paths.
     * Uses ReplicationStatusProvider.getBatchReplicationStatus(Resource...)
     * which is more efficient than per-path Replicator.getReplicationStatus() calls.
     */
    public Map<String, Boolean> checkPublishedState(ResourceResolver resolver, String[] paths) {
        // Resolve all paths to Resource objects
        Resource[] resources = Arrays.stream(paths)
            .map(resolver::getResource)
            .filter(Objects::nonNull)
            .toArray(Resource[]::new);

        // Single batch call — returns Map<path, ReplicationStatus>
        Map<String, ReplicationStatus> statusMap =
            replicationStatusProvider.getBatchReplicationStatus(resources);

        Map<String, Boolean> result = new LinkedHashMap<>();
        for (String path : paths) {
            ReplicationStatus status = statusMap.get(path);
            result.put(path, status != null && status.isActivated());
        }
        return result;
    }
}

Required imports:

import java.util.Arrays;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Objects;

Permission Checks

Example: Validate User Can Replicate

public class PermissionValidator {
    
    @Reference
    private Replicator replicator;
    
    /**
     * Check if user has permission to replicate
     */
    public boolean canUserReplicate(Session session, String path) {
        try {
            replicator.checkPermission(
                session,
                ReplicationActionType.ACTIVATE,
                path
            );
            return true;
        } catch (ReplicationException e) {
            // User lacks permission
            return false;
        }
    }
    
    /**
     * Validate before replicating
     */
    public void safeReplicate(Session session, String path) 
            throws ReplicationException {
        
        // Check permission first
        replicator.checkPermission(session, ReplicationActionType.ACTIVATE, path);
        
        // Proceed with replication
        replicator.replicate(session, ReplicationActionType.ACTIVATE, path);
    }
}

Workflow Integration

Example: Workflow Process Step

import com.adobe.granite.workflow.WorkflowException;
import com.adobe.granite.workflow.WorkflowSession;
import com.adobe.granite.workflow.exec.WorkItem;
import com.adobe.granite.workflow.exec.WorkflowProcess;
import com.adobe.granite.workflow.metadata.MetaDataMap;
import org.osgi.service.component.annotations.Component;

@Component(
    service = WorkflowProcess.class,
    property = {
        "process.label=Publish Content to Publish Tier"
    }
)
public class PublishWorkflowProcess implements WorkflowProcess {
    
    @Reference
    private Replicator replicator;
    
    @Override
    public void execute(WorkItem workItem, WorkflowSession workflowSession, 
                       MetaDataMap args) throws WorkflowException {
        
        String payloadPath = workItem.getWorkflowData().getPayload().toString();
        
        try {
            Session session = workflowSession.adaptTo(Session.class);
            
            replicator.replicate(
                session,
                ReplicationActionType.ACTIVATE,
                payloadPath
            );
            
        } catch (ReplicationException e) {
            throw new WorkflowException("Failed to publish content", e);
        }
    }
}

Process Arguments (configured in workflow model):

• Can use MetaDataMap args to pass custom parameters like target tier

Listening to Replication Events

Use OSGi Event Handlers to react to replication events:

import org.osgi.service.component.annotations.Component;
import org.osgi.service.event.Event;
import org.osgi.service.event.EventHandler;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

@Component(
    service = EventHandler.class,
    property = {
        org.osgi.service.event.EventConstants.EVENT_TOPIC + "=" + "com/day/cq/replication"
    }
)
public class ReplicationEventLogger implements EventHandler {
    
    private static final Logger LOG = LoggerFactory.getLogger(ReplicationEventLogger.class);
    
    @Override
    public void handleEvent(Event event) {
        String[] paths = (String[]) event.getProperty("paths");
        String action = (String) event.getProperty("action");
        String userId = (String) event.getProperty("userId");
        
        if (paths != null) {
            for (String path : paths) {
                LOG.info("Replication: action={}, path={}, user={}", action, path, userId);
            }
        }
    }
}

Event Properties:

• paths - Array of replicated paths
• action - Replication action (Activate, Deactivate, etc.)
• userId - User who triggered replication

Best Practices

1. Respect Rate Limits

• ≤100 paths per call for transactional guarantee; system auto-splits if exceeded
• ≤10 MB payload size

2. Use Workflow for Large Operations

Don't build custom bulk publishing code. Use Tree Activation workflow step.

3. Validate Permissions

Always check permissions before replication to avoid exceptions.

4. Use Service Users

Never replicate with admin credentials. Map a sub-service name to the principal that holds crx:replicate via ServiceUserMapperImpl.amended config. Provision the principal with jcr:read + crx:replicate on /content via Repo Init scripts — see AEM Project Structure — Repo Init. See references/patterns.md for the full service user setup example.

5. Publish Only What's Needed

Minimize replication volume to reduce queue pressure and pipeline load.

Common Patterns

See references/patterns.md for complete implementations:

• Auto-Publish on Content Fragment Save — event-driven publish using SlingConstants.TOPIC_RESOURCE_CHANGED
• External Cache Purge After Publication — CDN invalidation via replication event handler
• Service User Setup for Replication — OSGi service user mapping and Repo Init provisioning

Troubleshooting

Issue: Replication Fails Silently

Check: Verify replication queues in Felix console (Sling Jobs console):

https://author-p<programId>-e<envId>.adobeaemcloud.com/system/console/slingjobs

Look for failed jobs with topic: com/day/cq/replication

Issue: Permission Errors

Error: javax.jcr.AccessDeniedException

Solution: Verify service user has replication permissions:

/content/mysite -> jcr:read, crx:replicate

Issue: Content Not Appearing

Check:

1. Verify replication status: replicator.getReplicationStatus()
2. Check logs for distribution errors
3. Verify target tier (Preview vs. Publish)

References

• Official Javadoc: https://developer.adobe.com/experience-manager/reference-materials/cloud-service/javadoc/com/day/cq/replication/package-summary.html
• Adobe Docs: https://experienceleague.adobe.com/docs/experience-manager-cloud-service/content/operations/replication.html
• Sling Distribution: https://sling.apache.org/documentation/bundles/content-distribution.html