net.sf.webdav.methods.DoHead Maven / Gradle / Ivy

/**
 * Copyright (C) 2006-2017 Apache Software Foundation (https://sourceforge.net/p/webdav-servlet, https://github.com/Commonjava/webdav-handler)
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *         http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package net.sf.webdav.methods;

import static net.sf.webdav.WebdavStatus.SC_NOT_FOUND;
import static net.sf.webdav.WebdavStatus.SC_NOT_MODIFIED;

import java.io.IOException;

import net.sf.webdav.StoredObject;
import net.sf.webdav.WebdavStatus;
import net.sf.webdav.exceptions.AccessDeniedException;
import net.sf.webdav.exceptions.ObjectAlreadyExistsException;
import net.sf.webdav.exceptions.WebdavException;
import net.sf.webdav.locking.ResourceLocks;
import net.sf.webdav.spi.IMimeTyper;
import net.sf.webdav.spi.ITransaction;
import net.sf.webdav.spi.IWebdavStore;
import net.sf.webdav.spi.WebdavRequest;
import net.sf.webdav.spi.WebdavResponse;

public class DoHead
    extends AbstractMethod
{

    protected String _dftIndexFile;

    protected IWebdavStore _store;

    protected String _insteadOf404;

    protected ResourceLocks _resourceLocks;

    protected IMimeTyper _mimeTyper;

    protected boolean _contentLength;

    private static org.slf4j.Logger LOG = org.slf4j.LoggerFactory.getLogger( DoHead.class );

    public DoHead( final IWebdavStore store, final String dftIndexFile, final String insteadOf404, final ResourceLocks resourceLocks,
                   final IMimeTyper mimeTyper, final boolean contentLengthHeader )
    {
        _store = store;
        _dftIndexFile = dftIndexFile;
        _insteadOf404 = insteadOf404;
        _resourceLocks = resourceLocks;
        _mimeTyper = mimeTyper;
        _contentLength = contentLengthHeader;
    }

    @Override
    public void execute( final ITransaction transaction, final WebdavRequest req, final WebdavResponse resp )
        throws IOException, WebdavException
    {

        // determines if the uri exists.

        boolean bUriExists = false;

        String path = getRelativePath( req );
        LOG.trace( "-- " + this.getClass()
                               .getName() );

        StoredObject so = _store.getStoredObject( transaction, path );
        if ( so == null )
        {
            if ( this._insteadOf404 != null && !_insteadOf404.trim()
                                                             .equals( "" ) )
            {
                path = this._insteadOf404;
                so = _store.getStoredObject( transaction, this._insteadOf404 );
            }
        }
        else
        {
            bUriExists = true;
        }

        if ( so != null )
        {
            if ( so.isFolder() )
            {
                if ( _dftIndexFile != null && !_dftIndexFile.trim()
                                                            .equals( "" ) )
                {
                    resp.sendRedirect( resp.encodeRedirectURL( req.getRequestURI() + this._dftIndexFile ) );
                    return;
                }
            }
            else if ( so.isNullResource() )
            {
                final String methodsAllowed = DeterminableMethod.determineMethodsAllowed( so );
                resp.addHeader( "Allow", methodsAllowed );
                resp.sendError( WebdavStatus.SC_METHOD_NOT_ALLOWED );
                return;
            }

            final String tempLockOwner = "doGet" + System.currentTimeMillis() + req.toString();

            if ( _resourceLocks.lock( transaction, path, tempLockOwner, false, 0, TEMP_TIMEOUT, TEMPORARY ) )
            {
                try
                {

                    final String eTagMatch = req.getHeader( "If-None-Match" );
                    if ( eTagMatch != null )
                    {
                        if ( eTagMatch.equals( getETag( so ) ) )
                        {
                            resp.setStatus( SC_NOT_MODIFIED );
                            return;
                        }
                    }

                    if ( so.isResource() )
                    {
                        // path points to a file but ends with / or \
                        if ( path.endsWith( "/" ) || ( path.endsWith( "\\" ) ) )
                        {
                            resp.sendError( SC_NOT_FOUND, req.getRequestURI() );
                        }
                        else
                        {

                            // setting headers
                            final long lastModified = so.getLastModified()
                                                        .getTime();
                            resp.setDateHeader( "last-modified", lastModified );

                            final String eTag = getETag( so );
                            resp.addHeader( "ETag", eTag );

                            final long resourceLength = so.getResourceLength();

                            if ( _contentLength )
                            {
                                if ( resourceLength > 0 )
                                {
                                    if ( resourceLength <= Integer.MAX_VALUE )
                                    {
                                        resp.setContentLength( (int) resourceLength );
                                    }
                                    else
                                    {
                                        resp.setHeader( "content-length", "" + resourceLength );
                                        // is "content-length" the right header?
                                        // is long a valid format?
                                    }
                                }
                            }

                            final String mimeType = _mimeTyper.getMimeType( path );
                            if ( mimeType != null )
                            {
                                resp.setContentType( mimeType );
                            }
                            else
                            {
                                final int lastSlash = path.replace( '\\', '/' )
                                                          .lastIndexOf( '/' );
                                final int lastDot = path.indexOf( ".", lastSlash );
                                if ( lastDot == -1 )
                                {
                                    resp.setContentType( "text/html" );
                                }
                            }

                            doBody( transaction, resp, path );
                        }
                    }
                    else
                    {
                        folderBody( transaction, path, resp, req );
                    }
                }
                catch ( final AccessDeniedException e )
                {
                    resp.sendError( WebdavStatus.SC_FORBIDDEN );
                }
                catch ( final ObjectAlreadyExistsException e )
                {
                    resp.sendError( WebdavStatus.SC_NOT_FOUND, req.getRequestURI() );
                }
                catch ( final WebdavException e )
                {
                    resp.sendError( WebdavStatus.SC_INTERNAL_SERVER_ERROR );
                }
                finally
                {
                    _resourceLocks.unlockTemporaryLockedObjects( transaction, path, tempLockOwner );
                }
            }
            else
            {
                resp.sendError( WebdavStatus.SC_INTERNAL_SERVER_ERROR );
            }
        }
        else
        {
            folderBody( transaction, path, resp, req );
        }

        if ( !bUriExists )
        {
            resp.setStatus( WebdavStatus.SC_NOT_FOUND );
        }

    }

    protected void folderBody( final ITransaction transaction, final String path, final WebdavResponse resp, final WebdavRequest req )
        throws IOException, WebdavException
    {
        // no body for HEAD
    }

    protected void doBody( final ITransaction transaction, final WebdavResponse resp, final String path )
        throws IOException, WebdavException
    {
        // no body for HEAD
    }
}