geronimo-opentracing-osgi/src/main/java/org/apache/geronimo/microprofile/opentracing/osgi/ConfigAdminOpenTracingConfig.java

/*
 * 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.geronimo.microprofile.opentracing.osgi;

import static java.util.Optional.ofNullable;

import java.io.IOException;

import org.apache.geronimo.microprofile.opentracing.common.config.GeronimoOpenTracingConfig;
import org.osgi.service.cm.Configuration;
import org.osgi.service.cm.ConfigurationAdmin;

public class ConfigAdminOpenTracingConfig implements GeronimoOpenTracingConfig {
    private volatile Configuration delegate;

    public ConfigAdminOpenTracingConfig() {
        ofNullable(OpenTracingActivator.INSTANCES.get(ConfigurationAdmin.class))
                .map(OpenTracingActivator.Tracked::getInstance)
                .map(ConfigurationAdmin.class::cast)
                .ifPresent(admin -> {
                    try {
                        delegate = admin.getConfiguration("geronimo.opentracing");
                    } catch (final IOException e) {
                        throw new IllegalArgumentException(e);
                    }
                });
    }

    @Override
    public String read(final String value, final String def) {
        return ofNullable(delegate).map(c -> c.getProperties().get(value)).map(String::valueOf).orElse(def);
    }
}