uri-resolver/src/main/java/org/gcube/datatransfer/resolver/listeners/UriResolverStartupListener.java

/**
 *
 */
package org.gcube.datatransfer.resolver.listeners;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.Properties;

import javax.servlet.ServletContext;
import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebListener;

//import org.gcube.datatransfer.resolver.caches.LoadingCatalogueApplicationProfilesCache;
import org.gcube.datatransfer.resolver.caches.LoadingGeonetworkInstanceCache;
import org.gcube.datatransfer.resolver.caches.LoadingGisViewerApplicationURLCache;
import org.gcube.datatransfer.resolver.caches.LoadingVREsScopeCache;
import org.gcube.datatransfer.resolver.gis.property.ApplicationProfilePropertyReader;
import org.gcube.datatransfer.resolver.gis.property.PropertyFileNotFoundException;
import org.gcube.smartgears.ContextProvider;
import org.gcube.smartgears.context.application.ApplicationContext;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;


/**
 * The listener interface for receiving startup events.
 * The class that is interested in processing a startup
 * event implements this interface, and the object created
 * with that class is registered with a component using the
 * component's <code>addStartupListener<code> method. When
 * the startup event occurs, that object's appropriate
 * method is invoked.
 *
 * @author Francesco Mangiacrapa francesco.mangiacrapa@isti.cnr.it
 * Nov 2, 2018
 */
@WebListener
public class UriResolverStartupListener implements ServletContextListener {

	private static Logger logger = LoggerFactory.getLogger(UriResolverStartupListener.class);

	public static final String GIS_VIEWER_GENERIC_RESOURCE_GCUBE_APPS_PROPERTIES = "gisviewerappgenericresource.properties";
	public static final String GEO_EXPLORER_GENERIC_RESOURCE_GCUBE_APPS_PROPERTIES = "geoexplorerappgenericresource.properties";

	protected static final String SECONDARY_TYPE = "SECONDARY_TYPE";
	protected static final String APP_ID = "APP_ID";

	public static final String ENV_SCOPE = "SCOPE"; //Environment Variable


	private static String rootContextScope = null;

	private static ApplicationProfilePropertyReader gisViewerProfile;
	private static ApplicationProfilePropertyReader geoExplorerProfile;

    /* (non-Javadoc)
     * @see javax.servlet.ServletContextListener#contextInitialized(javax.servlet.ServletContextEvent)
     */
    @Override
    public void contextInitialized(ServletContextEvent event) {

    	try {
    		rootContextScope = loadScopeFromEnvironment();
        	ApplicationContext ctx = ContextProvider.get();
        	String rootScope = ctx.container().configuration().infrastructure();
        	logger.info("The ContextProvider returned the infrastructure name: "+rootScope);
		}
		catch (Exception e) {
			//
			logger.error(e.getMessage(), e);
		}

        gisViewerProfile = loadApplicationProfile(event.getServletContext(), GIS_VIEWER_GENERIC_RESOURCE_GCUBE_APPS_PROPERTIES);
        geoExplorerProfile = loadApplicationProfile(event.getServletContext(), GEO_EXPLORER_GENERIC_RESOURCE_GCUBE_APPS_PROPERTIES);
        //init the caches
        new LoadingGeonetworkInstanceCache();
        new LoadingGisViewerApplicationURLCache();
        new LoadingVREsScopeCache();
        //new LoadingCatalogueApplicationProfilesCache();

        logger.info("Context initialized with: ");
        logger.info("Scope: "+rootContextScope);
        logger.info("GisViewerProfile [ID: "+gisViewerProfile.getAppId() + ", Generic Resource Type: "+gisViewerProfile.getGenericResource()+"]");
        logger.info("GeoExplorerProfile [ID: "+geoExplorerProfile. getAppId() + ", Generic Resource Type: "+geoExplorerProfile.getGenericResource()+"]");
    }

    /* (non-Javadoc)
     * @see javax.servlet.ServletContextListener#contextDestroyed(javax.servlet.ServletContextEvent)
     */
    @Override
    public void contextDestroyed(ServletContextEvent event) {
        // Perform action during application's shutdown
    }

    /**
     * Gets the currency.
     *
     * @param context the context
     * @param propertyFileName the property file name
     * @return the currency
     */
    private static ApplicationProfilePropertyReader loadApplicationProfile(ServletContext context, String propertyFileName) {

        String contextPath = "/WEB-INF/property/"+propertyFileName;
        String realPath = context.getRealPath(contextPath);
        try {
            Properties props = new Properties();
            props.load(new FileInputStream(new File(realPath)));
			return new ApplicationProfilePropertyReader(new FileInputStream(new File(realPath)));

        } catch (PropertyFileNotFoundException | FileNotFoundException ex) {
        	logger.error("PropertyFileNotFoundException: "+contextPath, ex);
        }catch (IOException e) {
        	logger.error("Error on loading property from: "+contextPath, e);
		}

        return null;
    }


	/**
	 * Load scope from environment.
	 *
	 * @return the scope read from Environment Variable
	 * @throws ServletException the servlet exception
	 */
	public static String loadScopeFromEnvironment() throws ServletException{

		logger.info("Reading Environment Variable "+ENV_SCOPE);
		String scopeFromEnv = System.getenv(ENV_SCOPE);

		if(scopeFromEnv == null || scopeFromEnv.isEmpty())
			throw new ServletException(UriResolverStartupListener.class.getName() +" cannot read scope from Environment Variable: "+ENV_SCOPE+", It is null or empty");

		logger.info("Read scope: "+scopeFromEnv+" from Environment Variable: "+ENV_SCOPE);
		return scopeFromEnv;
	}


	/**
	 * Gets the gis viewer profile.
	 *
	 * @return the gis viewer profile
	 */
	public static ApplicationProfilePropertyReader getGisViewerProfile() {

		return gisViewerProfile;
	}


	/**
	 * Gets the geo explorer profile.
	 *
	 * @return the geoExplorerProfile
	 */
	public static ApplicationProfilePropertyReader getGeoExplorerProfile() {

		return geoExplorerProfile;
	}


	/**
	 * Gets the root context scope.
	 *
	 * @return the root context scope
	 */
	public static String getRootContextScope() {

		return rootContextScope;
	}



}