/*
* Licensed 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 com.facebook.presto.server;
import com.facebook.presto.execution.buffer.SerializedPage;
import com.facebook.presto.spi.Page;
import com.google.common.base.Throwables;
import com.google.common.reflect.TypeToken;
import io.airlift.slice.OutputStreamSliceOutput;
import io.airlift.slice.SliceOutput;
import javax.ws.rs.Produces;
import javax.ws.rs.WebApplicationException;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.MultivaluedMap;
import javax.ws.rs.ext.MessageBodyWriter;
import javax.ws.rs.ext.Provider;
import java.io.EOFException;
import java.io.IOException;
import java.io.OutputStream;
import java.io.UncheckedIOException;
import java.lang.annotation.Annotation;
import java.lang.reflect.Type;
import java.util.List;
import static com.facebook.presto.PrestoMediaTypes.PRESTO_PAGES;
import static com.facebook.presto.execution.buffer.PagesSerdeUtil.writeSerializedPages;
@Provider
@Produces(PRESTO_PAGES)
public class PagesResponseWriter
implements MessageBodyWriter<List<SerializedPage>>
{
private static final MediaType PRESTO_PAGES_TYPE = MediaType.valueOf(PRESTO_PAGES);
private static final Type LIST_GENERIC_TOKEN;
static {
try {
LIST_GENERIC_TOKEN = List.class.getMethod("get", int.class).getGenericReturnType();
}
catch (NoSuchMethodException e) {
throw Throwables.propagate(e);
}
}
@Override
public boolean isWriteable(Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType)
{
return List.class.isAssignableFrom(type) &&
TypeToken.of(genericType).resolveType(LIST_GENERIC_TOKEN).getRawType().equals(Page.class) &&
mediaType.isCompatible(PRESTO_PAGES_TYPE);
}
@Override
public long getSize(List<SerializedPage> serializedPages, Class<?> type, Type genericType, Annotation[] annotations, MediaType mediaType)
{
return -1;
}
@Override
public void writeTo(List<SerializedPage> serializedPages,
Class<?> type,
Type genericType,
Annotation[] annotations,
MediaType mediaType,
MultivaluedMap<String, Object> httpHeaders,
OutputStream output)
throws IOException, WebApplicationException
{
try {
SliceOutput sliceOutput = new OutputStreamSliceOutput(output);
writeSerializedPages(sliceOutput, serializedPages);
// We use flush instead of close, because the underlying stream would be closed and that is not allowed.
sliceOutput.flush();
}
catch (UncheckedIOException e) {
// EOF exception occurs when the client disconnects while writing data
// This is not a "server" problem so we don't want to log this
if (!(e.getCause() instanceof EOFException)) {
throw e;
}
}
}
}