content

package aws.servlet.heartbeat;

import javax.inject.Inject;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.Date;
import info.magnolia.objectfactory.Components;
import info.magnolia.module.ModuleManager;
import info.magnolia.cms.beans.config.ConfigLoader;
import info.magnolia.cms.beans.config.VersionConfig;
import info.magnolia.cms.beans.config.ServerConfiguration;
import info.magnolia.publishing.PublishingCoreModule;

// deploy under "/.magnolia/awsHeartbeat"
public class AWSHeartbeatServlet extends HttpServlet {


    private boolean provisioned = false;
    private long lastProvisioningRequest = Long.MIN_VALUE;
    private boolean publicsAreReady = false;

    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {

        if (provisioned && selfReady() && isPublicProfile() {
            // public instance is ready when provisioned, installed and reachable by http
            response.setStatus(200);
        if (provisioned && selfReady() && !isPublicProfile && publicsAreReady)) {
            // author instance is ready when provisioned, installed and all it's publics are reachable by http
            response.setStatus(200);
        } else {
            response.setStatus(503);
            long now = new Date().getTime();
            // wait for 5 minutes before asking public directly (might want to make this configurable)
            if (now - lastProvisioningRequest > 300) {
                lastProvisioningRequest = now;
                publicsAreReady = true;
                try {
                    for (Receiver receiver: Components.getComponent(PublishingCoreModule.class).getReceivers()) {
                        String url = receiver.getUrl() + "/.magnolia/awsHeartbeat"
                        URL url = new URL(url);
                        HttpURLConnection http = (HttpURLConnection)url.openConnection();
                        publicsAreReady &= (http.getResponseCode() == 200);
                    }
                } catch (Exception e) {
                    publicsAreReady = false;
                }
            }
        }
        
    }
    
    protected boolean isPublicProfile() {
        return Components.getComponent(ServerConfiguration.class).isAdmin();
    }
    protected boolean selfReady() {
        boolean ready = true;
        try {
            ready = MgnlContext.hasInstance();
            moduleManager = Components.getComponent(ModuleManager.class);
            configLoader = Components.getComponent(ConfigLoader.class);
        } catch (Exception e) {
            ready = false;
        }
        return ready && !mm.getStatus().needsUpdateOrInstall();
    }


    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        // got notified by AWS that provisioning is finished
        provisioned = true;
    }
}