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.api;
019
020import static javax.ws.rs.core.Response.created;
021import static javax.ws.rs.core.Response.noContent;
022import static javax.ws.rs.core.Response.status;
023import static javax.ws.rs.core.Response.Status.BAD_REQUEST;
024import static org.slf4j.LoggerFactory.getLogger;
025
026import java.net.URI;
027import java.net.URISyntaxException;
028import java.security.Principal;
029
030import javax.inject.Inject;
031import javax.servlet.http.HttpServletRequest;
032import javax.ws.rs.POST;
033import javax.ws.rs.Path;
034import javax.ws.rs.PathParam;
035import javax.ws.rs.core.Context;
036import javax.ws.rs.core.Response;
037
038import org.fcrepo.kernel.api.Transaction;
039import org.fcrepo.kernel.api.TxSession;
040import org.fcrepo.kernel.api.services.TransactionService;
041import org.slf4j.Logger;
042import org.springframework.context.annotation.Scope;
043
044/**
045 * Transactions over REST
046 *
047 * @author awoods
048 * @author gregjan
049 */
050@Scope("prototype")
051@Path("/{path: .*}/fcr:tx")
052public class FedoraTransactions extends FedoraBaseResource {
053
054    private static final Logger LOGGER = getLogger(FedoraTransactions.class);
055
056    @Inject
057    private TransactionService txService;
058
059    /**
060     * Create a new transaction resource and add it to the registry
061     *
062     * @param externalPath the external path
063     * @param req the http servlet request
064     * @return 201 with the transaction id and expiration date
065     * @throws URISyntaxException if URI syntax exception occurred
066     */
067    @POST
068    public Response createTransaction(@PathParam("path") final String externalPath,
069                                      @Context final HttpServletRequest req) throws URISyntaxException {
070
071        if (session instanceof TxSession) {
072            final Transaction t = txService.getTransaction(session);
073            LOGGER.debug("renewing transaction {}", t.getId());
074            t.updateExpiryDate();
075            return noContent().expires(t.getExpires()).build();
076        }
077
078        if (externalPath != null && !externalPath.isEmpty()) {
079            return status(BAD_REQUEST).build();
080        }
081
082        final Principal userPrincipal = req.getUserPrincipal();
083        String userName = null;
084        if (userPrincipal != null) {
085            userName = userPrincipal.getName();
086        }
087
088        final Transaction t = txService.beginTransaction(session, userName);
089        LOGGER.info("Created transaction '{}'", t.getId());
090
091        return created(new URI(translator().toDomain("/tx:" + t.getId()).toString())).expires(
092                t.getExpires()).build();
093    }
094
095    /**
096     * Commit a transaction resource
097     *
098     * @param externalPath the external path
099     * @return 204
100     */
101    @POST
102    @Path("fcr:commit")
103    public Response commit(@PathParam("path") final String externalPath) {
104        LOGGER.info("Commit transaction '{}'", externalPath);
105        return finalizeTransaction(externalPath, true);
106
107    }
108
109    /**
110     * Rollback a transaction
111     *
112     * @param externalPath the external path
113     * @return 204
114     */
115    @POST
116    @Path("fcr:rollback")
117    public Response rollback(@PathParam("path") final String externalPath) {
118        LOGGER.info("Rollback transaction '{}'", externalPath);
119        return finalizeTransaction(externalPath, false);
120    }
121
122    private Response finalizeTransaction(@PathParam("path")
123        final String externalPath, final boolean commit) {
124
125        final String path = toPath(translator(), externalPath);
126        if (!path.equals("/")) {
127            return status(BAD_REQUEST).build();
128        }
129
130        final String txId;
131        if (session instanceof TxSession) {
132            txId = ((TxSession) session).getTxId();
133        } else {
134            txId = "";
135        }
136
137        if (txId.isEmpty()) {
138            LOGGER.debug("cannot finalize an empty tx id {} at path {}",
139                    txId, path);
140            return status(BAD_REQUEST).build();
141        }
142
143        if (commit) {
144            LOGGER.debug("commiting transaction {} at path {}", txId, path);
145            txService.commit(txId);
146
147        } else {
148            LOGGER.debug("rolling back transaction {} at path {}", txId,
149                    path);
150            txService.rollback(txId);
151        }
152        return noContent().build();
153    }
154}