/*
* Copyright 2010 Proofpoint, Inc.
*
* 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 io.airlift.discovery.client.testing;
import com.google.common.base.Function;
import com.google.common.base.Preconditions;
import com.google.common.base.Throwables;
import com.google.common.collect.ImmutableList;
import com.google.common.util.concurrent.Futures;
import com.google.common.util.concurrent.ListenableFuture;
import io.airlift.discovery.client.DiscoveryException;
import io.airlift.discovery.client.DiscoveryLookupClient;
import io.airlift.discovery.client.ServiceDescriptor;
import io.airlift.discovery.client.ServiceDescriptors;
import io.airlift.discovery.client.ServiceSelector;
import io.airlift.discovery.client.ServiceSelectorConfig;
import io.airlift.log.Logger;
import java.util.List;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Future;
public class SimpleServiceSelector implements ServiceSelector
{
private static final Logger log = Logger.get(SimpleServiceSelector.class);
private final String type;
private final String pool;
private final DiscoveryLookupClient lookupClient;
public SimpleServiceSelector(String type, ServiceSelectorConfig selectorConfig, DiscoveryLookupClient lookupClient)
{
Preconditions.checkNotNull(type, "type is null");
Preconditions.checkNotNull(selectorConfig, "selectorConfig is null");
Preconditions.checkNotNull(lookupClient, "client is null");
this.type = type;
this.pool = selectorConfig.getPool();
this.lookupClient = lookupClient;
}
@Override
public String getType()
{
return type;
}
@Override
public String getPool()
{
return pool;
}
@Override
public List<ServiceDescriptor> selectAllServices()
{
try {
ListenableFuture<ServiceDescriptors> future = lookupClient.getServices(type, pool);
ServiceDescriptors serviceDescriptors = getFutureResult(future, DiscoveryException.class);
return serviceDescriptors.getServiceDescriptors();
}
catch (DiscoveryException e) {
log.error(e);
return ImmutableList.of();
}
}
@Override
public ListenableFuture<List<ServiceDescriptor>> refresh()
{
return Futures.transform(lookupClient.getServices(type, pool), new Function<ServiceDescriptors, List<ServiceDescriptor>>()
{
@Override
public List<ServiceDescriptor> apply(ServiceDescriptors serviceDescriptors)
{
return serviceDescriptors.getServiceDescriptors();
}
});
}
// TODO: move this to a utility package
private static <T, X extends Throwable> T getFutureResult(Future<T> future, Class<X> type)
throws X
{
try {
return future.get();
}
catch (InterruptedException e) {
Thread.currentThread().interrupt();
throw Throwables.propagate(e);
}
catch (ExecutionException e) {
Throwables.propagateIfPossible(e.getCause(), type);
throw Throwables.propagate(e.getCause());
}
}
}