/*
 * 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.bookkeeper.common.resolver;

import com.google.common.collect.Lists;
import io.grpc.Attributes;
import io.grpc.EquivalentAddressGroup;
import java.net.InetSocketAddress;
import java.net.URI;
import java.util.Collections;
import java.util.List;
import java.util.concurrent.ExecutorService;
import java.util.stream.Collectors;
import org.apache.bookkeeper.common.util.SharedResourceManager.Resource;

/**
 * A simple name resolver that returns pre-configured host addresses.
 */
public class StaticNameResolver extends AbstractNameResolver {

    private final List<EquivalentAddressGroup> servers;

    public StaticNameResolver(String name,
                              Resource<ExecutorService> executorResource,
                              List<URI> endpoints) {
        super(name, executorResource);
        this.servers = Collections.unmodifiableList(
            endpoints.stream()
                .map(endpoint -> new EquivalentAddressGroup(
                    Lists.newArrayList(new InetSocketAddress(endpoint.getHost(), endpoint.getPort())),
                    Attributes.EMPTY))
                .collect(Collectors.toList()));
    }

    @Override
    public List<EquivalentAddressGroup> getServers() {
        return servers;
    }
}
