001    /**
002     * Licensed to the Apache Software Foundation (ASF) under one
003     * or more contributor license agreements.  See the NOTICE file
004     * distributed with this work for additional information
005     * regarding copyright ownership.  The ASF licenses this file
006     * to you under the Apache License, Version 2.0 (the
007     * "License"); you may not use this file except in compliance
008     * 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     */
018    package org.apache.hadoop.hdfs.web.resources;
019    
020    import java.io.FileNotFoundException;
021    import java.io.IOException;
022    
023    import javax.servlet.http.HttpServletResponse;
024    import javax.ws.rs.core.Context;
025    import javax.ws.rs.core.MediaType;
026    import javax.ws.rs.core.Response;
027    import javax.ws.rs.ext.ExceptionMapper;
028    import javax.ws.rs.ext.Provider;
029    
030    import org.apache.commons.logging.Log;
031    import org.apache.commons.logging.LogFactory;
032    import org.apache.hadoop.hdfs.web.JsonUtil;
033    import org.apache.hadoop.ipc.RemoteException;
034    import org.apache.hadoop.security.authorize.AuthorizationException;
035    
036    import com.sun.jersey.api.ParamException;
037    import com.sun.jersey.api.container.ContainerException;
038    
039    /** Handle exceptions. */
040    @Provider
041    public class ExceptionHandler implements ExceptionMapper<Exception> {
042      public static final Log LOG = LogFactory.getLog(ExceptionHandler.class);
043    
044      private static Exception toCause(Exception e) {
045        final Throwable t = e.getCause();
046        if (t != null && t instanceof Exception) {
047          e = (Exception)e.getCause();
048        }
049        return e;
050      }
051    
052      private @Context HttpServletResponse response;
053    
054      @Override
055      public Response toResponse(Exception e) {
056        if (LOG.isTraceEnabled()) {
057          LOG.trace("GOT EXCEPITION", e);
058        }
059    
060        //clear content type
061        response.setContentType(null);
062    
063        //Convert exception
064        if (e instanceof ParamException) {
065          final ParamException paramexception = (ParamException)e;
066          e = new IllegalArgumentException("Invalid value for webhdfs parameter \""
067              + paramexception.getParameterName() + "\": "
068              + e.getCause().getMessage(), e);
069        }
070        if (e instanceof ContainerException) {
071          e = toCause(e);
072        }
073        if (e instanceof RemoteException) {
074          e = ((RemoteException)e).unwrapRemoteException();
075        }
076    
077        //Map response status
078        final Response.Status s;
079        if (e instanceof SecurityException) {
080          s = Response.Status.UNAUTHORIZED;
081        } else if (e instanceof AuthorizationException) {
082          s = Response.Status.UNAUTHORIZED;
083        } else if (e instanceof FileNotFoundException) {
084          s = Response.Status.NOT_FOUND;
085        } else if (e instanceof IOException) {
086          s = Response.Status.FORBIDDEN;
087        } else if (e instanceof UnsupportedOperationException) {
088          s = Response.Status.BAD_REQUEST;
089        } else if (e instanceof IllegalArgumentException) {
090          s = Response.Status.BAD_REQUEST;
091        } else {
092          LOG.warn("INTERNAL_SERVER_ERROR", e);
093          s = Response.Status.INTERNAL_SERVER_ERROR;
094        }
095     
096        final String js = JsonUtil.toJsonString(e);
097        return Response.status(s).type(MediaType.APPLICATION_JSON).entity(js).build();
098      }
099    }