ImageHandler.java

/*
 * Copyright 2000-2013 Enonic AS
 * http://www.enonic.com/license
 */

package com.enonic.cms.web.portal.image;

import java.io.IOException;
import java.util.Enumeration;
import java.util.HashMap;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.joda.time.DateTime;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

import com.enonic.cms.framework.util.HttpServletUtil;

import com.enonic.cms.core.Attribute;
import com.enonic.cms.core.Path;
import com.enonic.cms.core.content.access.ContentAccessResolver;
import com.enonic.cms.core.image.ImageRequest;
import com.enonic.cms.core.image.ImageRequestParser;
import com.enonic.cms.core.image.ImageResponse;
import com.enonic.cms.core.portal.ReservedLocalPaths;
import com.enonic.cms.core.portal.ResourceNotFoundException;
import com.enonic.cms.core.portal.image.ImageProcessorException;
import com.enonic.cms.core.portal.image.ImageRequestAccessResolver;
import com.enonic.cms.core.portal.image.ImageService;
import com.enonic.cms.core.portal.livetrace.ImageRequestTrace;
import com.enonic.cms.core.portal.livetrace.ImageRequestTracer;
import com.enonic.cms.core.portal.livetrace.PortalRequestTrace;
import com.enonic.cms.core.portal.livetrace.PortalRequestTracer;
import com.enonic.cms.core.portal.rendering.tracing.RenderTrace;
import com.enonic.cms.core.security.user.UserEntity;
import com.enonic.cms.core.structure.SiteEntity;
import com.enonic.cms.core.structure.SitePath;
import com.enonic.cms.core.structure.SiteProperties;
import com.enonic.cms.core.structure.SitePropertyNames;
import com.enonic.cms.core.structure.menuitem.MenuItemEntity;
import com.enonic.cms.web.portal.PortalWebContext;
import com.enonic.cms.web.portal.handler.WebHandlerBase;

@Component
public final class ImageHandler
    extends WebHandlerBase
{
    private ImageService imageService;

    private final ImageRequestParser requestParser = new ImageRequestParser();

    @Override
    protected boolean canHandle( final Path localPath )
    {
        return localPath.containsSubPath( "_image" );
    }

    @Override
    protected void doHandle( final PortalWebContext context )
        throws Exception
    {
        final HttpServletRequest request = context.getRequest();
        final HttpServletResponse response = context.getResponse();
        final SitePath sitePath = context.getSitePath();
        final UserEntity loggedInUser;

        final PortalRequestTrace portalRequestTrace =
            PortalRequestTracer.startTracing( (String) request.getAttribute( Attribute.ORIGINAL_URL ), livePortalTraceService );
        try
        {
            final ImageResponse imageResponse;
            try
            {
                PortalRequestTracer.traceMode( portalRequestTrace, previewService );
                PortalRequestTracer.traceHttpRequest( portalRequestTrace, request );
                PortalRequestTracer.traceRequestedSitePath( portalRequestTrace, sitePath );
                PortalRequestTracer.traceRequestedSite( portalRequestTrace, siteDao.findByKey( sitePath.getSiteKey() ) );

                loggedInUser = resolveLoggedInUser( request, response, sitePath );
                PortalRequestTracer.traceRequester( portalRequestTrace, loggedInUser );

                final ImageRequestTrace imageRequestTrace = ImageRequestTracer.startTracing( livePortalTraceService );
                try
                {
                    verifyValidMenuItemInPath( sitePath );

                    final ImageRequest imageRequest = createImageRequest( request );
                    try
                    {
                        imageResponse = processImageRequest( imageRequest, sitePath, imageRequestTrace );
                    }
                    catch ( ImageProcessorException e )
                    {
                        response.sendError( HttpServletResponse.SC_INTERNAL_SERVER_ERROR, e.getMessage() );
                        return;
                    }

                    ImageRequestTracer.traceSize( imageRequestTrace, (long) imageResponse.getSize() );
                }
                finally
                {
                    ImageRequestTracer.stopTracing( imageRequestTrace, livePortalTraceService );
                }
            }
            finally
            {
                PortalRequestTracer.stopTracing( portalRequestTrace, livePortalTraceService );
            }

            serveResponse( response, sitePath, imageResponse );
        }
        catch ( Exception e )
        {
            throw new ImageRequestException( sitePath, request.getHeader( "referer" ), e );
        }
    }

    private ImageResponse processImageRequest( final ImageRequest imageRequest, final SitePath sitePath,
                                               final ImageRequestTrace imageRequestTrace )
        throws ImageProcessorException
    {
        ImageRequestTracer.traceImageRequest( imageRequestTrace, imageRequest );
        checkRequestAccess( imageRequest, sitePath );

        final ImageResponse imageResponse = imageService.process( imageRequest );

        if ( imageResponse.isImageNotFound() )
        {
            throw new ResourceNotFoundException( sitePath.getSiteKey(), sitePath.getLocalPath() );
        }
        return imageResponse;
    }

    private void serveResponse( final HttpServletResponse response, final SitePath sitePath, final ImageResponse imageResponse )
        throws IOException
    {
        final boolean anonymousAccess = securityService.getLoggedInPortalUser().isAnonymous();
        setHttpHeaders( response, sitePath, anonymousAccess );

        response.setContentType( imageResponse.getMimeType() );
        response.setContentLength( imageResponse.getSize() );
        HttpServletUtil.setContentDisposition( response, false, imageResponse.getName() );
        HttpServletUtil.copyNoCloseOut( imageResponse.getDataAsStream(), response.getOutputStream() );
    }

    private UserEntity resolveLoggedInUser( final HttpServletRequest request, final HttpServletResponse response, final SitePath sitePath )
    {
        UserEntity loggedInUser = securityService.getLoggedInPortalUserAsEntity();
        final SiteProperties siteProperties = sitePropertiesService.getSiteProperties( sitePath.getSiteKey() );
        if ( loggedInUser.isAnonymous() )
        {
            if ( siteProperties.getPropertyAsBoolean( SitePropertyNames.AUTOLOGIN_HTTP_REMOTE_USER_ENABLED ) )
            {
                loggedInUser = autoLoginService.autologinWithRemoteUser( request, siteDao.findByKey( sitePath.getSiteKey() ) );
            }
        }
        if ( loggedInUser.isAnonymous() )
        {
            if ( siteProperties.getPropertyAsBoolean( SitePropertyNames.AUTOLOGIN_REMEMBER_ME_COOKIE_ENABLED ) )
            {
                loggedInUser = autoLoginService.autologinWithCookie( siteDao.findByKey( sitePath.getSiteKey() ), request, response );
            }
        }
        return loggedInUser;
    }

    private ImageRequest createImageRequest( final HttpServletRequest request )
    {
        final HashMap<String, String> params = new HashMap<String, String>();
        final Enumeration e = request.getParameterNames();

        while ( e.hasMoreElements() )
        {
            final String key = (String) e.nextElement();
            params.put( key, request.getParameter( key ) );
        }

        final boolean encodeParams = !RenderTrace.isExecutingInDebugMode();
        final ImageRequest imageRequest = requestParser.parse( request.getPathInfo(), params, encodeParams );

        imageRequest.setRequester( securityService.getLoggedInPortalUser() );
        imageRequest.setRequestDateTime( new DateTime() );
        return imageRequest;
    }

    private void verifyValidMenuItemInPath( final SitePath sitePath )
    {
        SiteEntity site = siteDao.findByKey( sitePath.getSiteKey() );

        Path menuItemPath = getImageMenuItemPath( sitePath );

        MenuItemEntity menuItem = site.resolveMenuItemByPath( menuItemPath );

        if ( menuItem == null )
        {
            throw new ResourceNotFoundException( sitePath.getSiteKey(), sitePath.getLocalPath() );
        }
    }

    private Path getImageMenuItemPath( final SitePath sitePath )
    {
        String pathAsString = sitePath.getLocalPath().toString();

        if ( !pathAsString.contains( ReservedLocalPaths.PATH_IMAGE.toString() ) )
        {
            throw new ResourceNotFoundException( sitePath.getSiteKey(), sitePath.getLocalPath() );
        }

        int i = pathAsString.lastIndexOf( ReservedLocalPaths.PATH_IMAGE.toString() );

        String menuItemPathAsString = pathAsString.substring( 0, i );

        return new Path( menuItemPathAsString );
    }

    private void setHttpHeaders( final HttpServletResponse response, final SitePath sitePath, final boolean anonymousAccess )
    {
        final DateTime now = new DateTime();
        HttpServletUtil.setDateHeader( response, now.toDate() );

        final SiteProperties siteProperties = sitePropertiesService.getSiteProperties( sitePath.getSiteKey() );
        final boolean cacheHeadersEnabled = siteProperties.getPropertyAsBoolean( SitePropertyNames.IMAGE_CACHE_HEADERS_ENABLED );
        if ( cacheHeadersEnabled )
        {
            final boolean forceNoCache = siteProperties.getPropertyAsBoolean( SitePropertyNames.IMAGE_CACHE_HEADERS_FORCENOCACHE );
            if ( forceNoCache )
            {
                HttpServletUtil.setCacheControlNoCache( response );
            }
            else
            {
                Integer siteCacheSettingsMaxAge = siteProperties.getPropertyAsInteger( SitePropertyNames.IMAGE_CACHE_HEADERS_MAXAGE );
                enableHttpCacheHeaders( response, sitePath, now, siteCacheSettingsMaxAge, anonymousAccess );
            }
        }
    }

    private void checkRequestAccess( final ImageRequest imageRequest, final SitePath sitePath )
    {
        final UserEntity loggedInPortalUser = securityService.getLoggedInPortalUserAsEntity();

        ImageRequestAccessResolver accessResolver = new ImageRequestAccessResolver( contentDao, new ContentAccessResolver( groupDao ) );
        accessResolver.imageRequester( loggedInPortalUser );
        accessResolver.requireMainVersion();
        accessResolver.requireOnlineNow( timeService.getNowAsDateTime(), previewService );
        final ImageRequestAccessResolver.Access access = accessResolver.isAccessible( imageRequest );

        if ( access != ImageRequestAccessResolver.Access.OK )
        {
            throw new ResourceNotFoundException( sitePath.getSiteKey(), sitePath.getLocalPath() );
        }
    }

    @Autowired
    public void setImageService( final ImageService imageService )
    {
        this.imageService = imageService;
    }
}