org.springframework.cloud.zookeeper.discovery.ZookeeperDiscoveryClient.java Source code

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Here is the source code for org.springframework.cloud.zookeeper.discovery.ZookeeperDiscoveryClient.java

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/*
 * Copyright 2013-2015 the original author or authors.
 *
 * 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 org.springframework.cloud.zookeeper.discovery;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.curator.x.discovery.ServiceInstance;
import org.springframework.cloud.client.DefaultServiceInstance;
import org.springframework.cloud.client.discovery.DiscoveryClient;
import org.springframework.cloud.zookeeper.discovery.dependency.ZookeeperDependencies;
import org.springframework.util.ReflectionUtils;

import static org.springframework.util.ReflectionUtils.rethrowRuntimeException;

/**
 * Zookeeper version of {@link DiscoveryClient}. Capable of resolving aliases from
 * {@link ZookeeperDependencies} to service names in Zookeeper.
 *
 * @author Spencer Gibb
 * @author Marcin Grzejszczak
 * @since 1.0.0
 */
public class ZookeeperDiscoveryClient implements DiscoveryClient {

    private static final Log log = LogFactory.getLog(ZookeeperDiscoveryClient.class);

    private ZookeeperServiceDiscovery serviceDiscovery;

    private ZookeeperDependencies zookeeperDependencies;

    public ZookeeperDiscoveryClient(ZookeeperServiceDiscovery serviceDiscovery,
            ZookeeperDependencies zookeeperDependencies) {
        this.serviceDiscovery = serviceDiscovery;
        this.zookeeperDependencies = zookeeperDependencies;
    }

    @Override
    public String description() {
        return "Spring Cloud Zookeeper Discovery Client";
    }

    @Override
    public org.springframework.cloud.client.ServiceInstance getLocalServiceInstance() {
        ServiceInstance<ZookeeperInstance> serviceInstance = this.serviceDiscovery.getServiceInstance();
        return serviceInstance == null ? null : createServiceInstance(serviceInstance.getName(), serviceInstance);
    }

    private static org.springframework.cloud.client.ServiceInstance createServiceInstance(String serviceId,
            ServiceInstance<ZookeeperInstance> serviceInstance) {
        boolean secure = serviceInstance.getSslPort() != null;
        Integer port = serviceInstance.getPort();
        if (secure) {
            port = serviceInstance.getSslPort();
        }
        Map<String, String> metadata;
        if (serviceInstance.getPayload() != null) {
            metadata = serviceInstance.getPayload().getMetadata();
        } else {
            metadata = new HashMap<>();
        }
        return new DefaultServiceInstance(serviceId, serviceInstance.getAddress(), port, secure, metadata);
    }

    @Override
    public List<org.springframework.cloud.client.ServiceInstance> getInstances(final String serviceId) {
        try {
            String serviceIdToQuery = getServiceIdToQuery(serviceId);
            Collection<ServiceInstance<ZookeeperInstance>> zkInstances = this.serviceDiscovery.getServiceDiscovery()
                    .queryForInstances(serviceIdToQuery);
            List<org.springframework.cloud.client.ServiceInstance> instances = new ArrayList<>();
            for (ServiceInstance<ZookeeperInstance> instance : zkInstances) {
                instances.add(createServiceInstance(serviceIdToQuery, instance));
            }
            return instances;
        } catch (Exception exception) {
            ReflectionUtils.rethrowRuntimeException(exception);
        }
        return new ArrayList<>();
    }

    private String getServiceIdToQuery(String serviceId) {
        if (this.zookeeperDependencies != null && this.zookeeperDependencies.hasDependencies()) {
            String pathForAlias = this.zookeeperDependencies.getPathForAlias(serviceId);
            return pathForAlias.isEmpty() ? serviceId : pathForAlias;
        }
        return serviceId;
    }

    @Override
    public List<String> getServices() {
        List<String> services = null;
        if (this.serviceDiscovery.getServiceDiscovery() == null) {
            log.warn("Service Discovery is not yet ready - returning empty list of services");
            return Collections.emptyList();
        }
        try {
            services = new ArrayList<>(this.serviceDiscovery.getServiceDiscovery().queryForNames());
        } catch (Exception e) {
            rethrowRuntimeException(e);
        }
        return services;
    }
}