/*
* Copyright 2010 The Apache Software Foundation
*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 org.apache.hadoop.hbase.stargate;
import java.io.IOException;
import javax.ws.rs.DELETE;
import javax.ws.rs.GET;
import javax.ws.rs.Produces;
import javax.ws.rs.QueryParam;
import javax.ws.rs.WebApplicationException;
import javax.ws.rs.core.CacheControl;
import javax.ws.rs.core.Context;
import javax.ws.rs.core.Response;
import javax.ws.rs.core.Response.ResponseBuilder;
import javax.ws.rs.core.UriInfo;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.hbase.KeyValue;
import org.apache.hadoop.hbase.stargate.model.CellModel;
import org.apache.hadoop.hbase.stargate.model.CellSetModel;
import org.apache.hadoop.hbase.stargate.model.RowModel;
import org.apache.hadoop.hbase.util.Bytes;
import com.sun.jersey.core.util.Base64;
public class ScannerInstanceResource implements Constants {
private static final Log LOG =
LogFactory.getLog(ScannerInstanceResource.class);
User user;
ResultGenerator generator;
String id;
int batch = 1;
RESTServlet servlet;
CacheControl cacheControl;
public ScannerInstanceResource(User user, String table, String id,
ResultGenerator generator, int batch) throws IOException {
this.user = user;
this.id = id;
this.generator = generator;
this.batch = batch;
servlet = RESTServlet.getInstance();
cacheControl = new CacheControl();
cacheControl.setNoCache(true);
cacheControl.setNoTransform(false);
}
@GET
@Produces({MIMETYPE_XML, MIMETYPE_JSON, MIMETYPE_PROTOBUF})
public Response get(final @Context UriInfo uriInfo,
@QueryParam("n") int maxRows, final @QueryParam("c") int maxValues)
throws IOException {
if (LOG.isDebugEnabled()) {
LOG.debug("GET " + uriInfo.getAbsolutePath());
}
servlet.getMetrics().incrementRequests(1);
CellSetModel model = new CellSetModel();
RowModel rowModel = null;
byte[] rowKey = null;
int limit = batch;
if (maxValues > 0) {
limit = maxValues;
}
int count = limit;
do {
KeyValue value = null;
try {
value = generator.next();
} catch (IllegalStateException e) {
ScannerResource.delete(id);
throw new WebApplicationException(Response.Status.GONE);
}
if (value == null) {
LOG.info("generator exhausted");
// respond with 204 (No Content) if an empty cell set would be
// returned
if (count == limit) {
return Response.noContent().build();
}
break;
}
if (rowKey == null) {
rowKey = value.getRow();
rowModel = new RowModel(rowKey);
}
if (!Bytes.equals(value.getRow(), rowKey)) {
// the user request limit is a transaction limit, so we need to
// account for scanner.next()
if (user != null && !servlet.userRequestLimit(user, 1)) {
generator.putBack(value);
break;
}
// if maxRows was given as a query param, stop if we would exceed the
// specified number of rows
if (maxRows > 0) {
if (--maxRows == 0) {
generator.putBack(value);
break;
}
}
model.addRow(rowModel);
rowKey = value.getRow();
rowModel = new RowModel(rowKey);
}
rowModel.addCell(
new CellModel(value.getColumn(), value.getTimestamp(),
value.getValue()));
} while (--count > 0);
model.addRow(rowModel);
ResponseBuilder response = Response.ok(model);
response.cacheControl(cacheControl);
return response.build();
}
@GET
@Produces(MIMETYPE_BINARY)
public Response getBinary(final @Context UriInfo uriInfo) {
if (LOG.isDebugEnabled()) {
LOG.debug("GET " + uriInfo.getAbsolutePath() + " as " +
MIMETYPE_BINARY);
}
servlet.getMetrics().incrementRequests(1);
try {
KeyValue value = generator.next();
if (value == null) {
LOG.info("generator exhausted");
return Response.noContent().build();
}
ResponseBuilder response = Response.ok(value.getValue());
response.cacheControl(cacheControl);
response.header("X-Row", Base64.encode(value.getRow()));
response.header("X-Column", Base64.encode(value.getColumn()));
response.header("X-Timestamp", value.getTimestamp());
return response.build();
} catch (IllegalStateException e) {
ScannerResource.delete(id);
throw new WebApplicationException(Response.Status.GONE);
}
}
@DELETE
public Response delete(final @Context UriInfo uriInfo) {
if (LOG.isDebugEnabled()) {
LOG.debug("DELETE " + uriInfo.getAbsolutePath());
}
servlet.getMetrics().incrementRequests(1);
ScannerResource.delete(id);
return Response.ok().build();
}
}