001/*
002 * Licensed to DuraSpace under one or more contributor license agreements.
003 * See the NOTICE file distributed with this work for additional information
004 * regarding copyright ownership.
005 *
006 * DuraSpace licenses this file to you under the Apache License,
007 * Version 2.0 (the "License"); you may not use this file except in
008 * compliance with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.fcrepo.http.commons.exceptionhandlers;
019
020import static javax.ws.rs.core.Response.status;
021import static javax.ws.rs.core.Response.Status.BAD_REQUEST;
022import static org.fcrepo.http.commons.domain.RDFMediaType.TEXT_PLAIN_WITH_CHARSET;
023import static org.fcrepo.kernel.api.RdfLexicon.CONSTRAINED_BY;
024import static org.slf4j.LoggerFactory.getLogger;
025
026import javax.ws.rs.core.Link;
027import javax.ws.rs.core.Response;
028import javax.ws.rs.ext.ExceptionMapper;
029import javax.ws.rs.ext.Provider;
030
031import org.fcrepo.kernel.api.exception.MalformedRdfException;
032
033import org.apache.commons.codec.binary.Base64;
034import org.slf4j.Logger;
035
036/**
037 * @author cabeer
038 * @since 9/30/14
039 */
040@Provider
041public class MalformedRdfExceptionMapper implements
042        ExceptionMapper<MalformedRdfException>, ExceptionDebugLogging {
043
044    private static final Logger LOGGER =
045            getLogger(MalformedRdfExceptionMapper.class);
046
047    private static final int REASONABLE_LENGTH = 500;
048
049    @Override
050    public Response toResponse(final MalformedRdfException e) {
051        debugException(this, e, LOGGER);
052        final Link link = Link.fromUri(getConstraintUri(e)).rel(CONSTRAINED_BY.getURI()).build();
053        final String msg = e.getMessage();
054        if (msg.matches(".*org.*Exception: .*")) {
055            return status(BAD_REQUEST).entity(msg.replaceAll("org.*Exception: ", "")).links(link).type(
056                    TEXT_PLAIN_WITH_CHARSET).build();
057        }
058        return status(BAD_REQUEST).entity(msg).links(link).type(TEXT_PLAIN_WITH_CHARSET).build();
059    }
060
061    private static String getConstraintUri(final MalformedRdfException e) {
062        final int index = Math.min(e.getMessage().length(), REASONABLE_LENGTH);
063        if (index > e.getMessage().length()) {
064            LOGGER.debug("Truncating Link header to {} characters.", REASONABLE_LENGTH);
065        }
066
067        return "data:text/plain;base64," + Base64.encodeBase64String(e.getMessage().substring(0, index).getBytes());
068    }
069}