001/**
002 * Copyright 2015 DuraSpace, Inc.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *     http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016package org.fcrepo.http.api;
017
018import static javax.ws.rs.core.Response.created;
019import static javax.ws.rs.core.Response.noContent;
020import static javax.ws.rs.core.Response.status;
021import static javax.ws.rs.core.Response.Status.BAD_REQUEST;
022import static org.slf4j.LoggerFactory.getLogger;
023
024import java.net.URI;
025import java.net.URISyntaxException;
026import java.security.Principal;
027
028import javax.inject.Inject;
029import javax.jcr.Session;
030import javax.servlet.http.HttpServletRequest;
031import javax.ws.rs.POST;
032import javax.ws.rs.Path;
033import javax.ws.rs.PathParam;
034import javax.ws.rs.core.Context;
035import javax.ws.rs.core.Response;
036
037import org.fcrepo.kernel.Transaction;
038import org.fcrepo.kernel.TxSession;
039import org.fcrepo.kernel.services.TransactionService;
040import org.slf4j.Logger;
041import org.springframework.beans.factory.annotation.Autowired;
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    @Autowired
057    private TransactionService txService;
058
059    @Inject
060    protected Session session;
061
062    /**
063     * Create a new transaction resource and add it to the registry
064     *
065     * @param externalPath
066     * @return 201 with the transaction id and expiration date
067     * @throws URISyntaxException
068     */
069    @POST
070    public Response createTransaction(@PathParam("path") final String externalPath,
071                                      @Context final HttpServletRequest req) throws URISyntaxException {
072
073        if (session instanceof TxSession) {
074            final Transaction t = txService.getTransaction(session);
075            LOGGER.debug("renewing transaction {}", t.getId());
076            t.updateExpiryDate();
077            return noContent().expires(t.getExpires()).build();
078        }
079
080        if (externalPath != null && !externalPath.isEmpty()) {
081            return status(BAD_REQUEST).build();
082        }
083
084        final Principal userPrincipal = req.getUserPrincipal();
085        String userName = null;
086        if (userPrincipal != null) {
087            userName = userPrincipal.getName();
088        }
089
090        final Transaction t = txService.beginTransaction(session, userName);
091        LOGGER.info("Created transaction '{}'", t.getId());
092
093        return created(new URI(translator().toDomain("/tx:" + t.getId()).toString())).expires(
094                t.getExpires()).build();
095    }
096
097    /**
098     * Commit a transaction resource
099     *
100     * @param externalPath
101     * @return 204
102     */
103    @POST
104    @Path("fcr:commit")
105    public Response commit(@PathParam("path") final String externalPath) {
106        LOGGER.info("Commit transaction '{}'", externalPath);
107        return finalizeTransaction(externalPath, true);
108
109    }
110
111    /**
112     * Rollback a transaction
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
155    @Override
156    protected Session session() {
157        return session;
158    }
159}