/*
 * Copyright 2012-2019 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
 *
 *      https://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.boot.actuate.autoconfigure.metrics;

import io.micrometer.core.instrument.Clock;
import io.micrometer.core.instrument.MeterRegistry;
import io.micrometer.core.instrument.composite.CompositeMeterRegistry;

import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

/**
 * Configuration for a no-op meter registry when the context does not contain an
 * auto-configured {@link MeterRegistry}.
 *
 * @author Andy Wilkinson
 */
@Configuration
@ConditionalOnBean(Clock.class)
@ConditionalOnMissingBean(MeterRegistry.class)
class NoOpMeterRegistryConfiguration {

	@Bean
	public CompositeMeterRegistry noOpMeterRegistry(Clock clock) {
		return new CompositeMeterRegistry(clock);
	}

}
