zipkin.autoconfigure.storage.elasticsearch.http.ZipkinElasticsearchHttpStorageAutoConfiguration.java Source code

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Here is the source code for zipkin.autoconfigure.storage.elasticsearch.http.ZipkinElasticsearchHttpStorageAutoConfiguration.java

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/**
 * Copyright 2015-2016 The OpenZipkin 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 zipkin.autoconfigure.storage.elasticsearch.http;

import com.google.common.base.Optional;
import java.util.Arrays;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Condition;
import org.springframework.context.annotation.ConditionContext;
import org.springframework.context.annotation.Conditional;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.type.AnnotatedTypeMetadata;
import zipkin.autoconfigure.storage.elasticsearch.ZipkinElasticsearchStorageAutoConfiguration;
import zipkin.storage.StorageComponent;

import static com.google.common.base.Preconditions.checkArgument;

@Configuration
@EnableConfigurationProperties(ZipkinElasticsearchHttpStorageProperties.class)
@ConditionalOnProperty(name = "zipkin.storage.type", havingValue = "elasticsearch")
@Conditional({ ZipkinElasticsearchHttpStorageAutoConfiguration.HostsAreUrls.class,
        ZipkinElasticsearchHttpStorageAutoConfiguration.HostsArentAwsUrls.class })
@ConditionalOnMissingBean(StorageComponent.class)
public class ZipkinElasticsearchHttpStorageAutoConfiguration {
    @Bean
    StorageComponent storage(ZipkinElasticsearchHttpStorageProperties elasticsearch) {
        return elasticsearch.toBuilder().build();
    }

    static final class HostsAreUrls implements Condition {
        @Override
        public boolean matches(ConditionContext condition, AnnotatedTypeMetadata md) {
            String hosts = condition.getEnvironment().getProperty("zipkin.storage.elasticsearch.hosts");
            if (hosts == null)
                return false;
            return ZipkinElasticsearchStorageAutoConfiguration.hostsAreUrls(hosts);
        }
    }

    static final class HostsArentAwsUrls implements Condition {
        @Override
        public boolean matches(ConditionContext condition, AnnotatedTypeMetadata md) {
            String hosts = condition.getEnvironment().getProperty("zipkin.storage.elasticsearch.hosts");
            if (hosts == null)
                return true;
            return !regionFromAwsUrls(Arrays.asList(hosts.split(","))).isPresent();
        }
    }

    /**
     * Only here for consumption by {@link HostsArentAwsUrls}; ideally we could find a way to express
     * a hierarchy of autoconfigurations in spring without each parent needing to turn themselves off
     * for their children, but there seems to be no reliable way to order autoconfigure'd classes
     * (neither @AutoConfigureBefore nor @AutoConfigureAfter seemd to have the desired effect)
     */
    private static final Pattern AWS_URL = Pattern.compile("^https://[^.]+\\.([^.]+)\\.es\\.amazonaws\\.com",
            Pattern.CASE_INSENSITIVE);

    public static Optional<String> regionFromAwsUrls(List<String> hosts) {
        Optional<String> awsRegion = Optional.absent();
        for (String url : hosts) {
            Matcher matcher = AWS_URL.matcher(url);
            if (matcher.find()) {
                String matched = matcher.group(1);
                checkArgument(awsRegion.or(matched).equals(matched), "too many regions: saw '%s' and '%s'",
                        awsRegion, matched);
                awsRegion = Optional.of(matcher.group(1));
            } else {
                checkArgument(!awsRegion.isPresent(), "mismatched regions; saw '%s' but no awsRegion found in '%s'",
                        awsRegion.orNull(), url);
            }
        }
        return awsRegion;
    }
}