001/*
002 * Copyright 2012-2018 the original author or authors.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.springframework.boot.actuate.autoconfigure.metrics;
018
019import java.util.concurrent.atomic.AtomicBoolean;
020import java.util.function.Supplier;
021
022import io.micrometer.core.instrument.Meter.Id;
023import io.micrometer.core.instrument.config.MeterFilter;
024import io.micrometer.core.instrument.config.MeterFilterReply;
025import org.apache.commons.logging.Log;
026import org.apache.commons.logging.LogFactory;
027
028import org.springframework.util.Assert;
029
030/**
031 * {@link MeterFilter} to log only once a warning message and deny a {@link Id Meter.Id}.
032 *
033 * @author Jon Schneider
034 * @author Dmytro Nosan
035 * @since 2.0.5
036 */
037public final class OnlyOnceLoggingDenyMeterFilter implements MeterFilter {
038
039        private static final Log logger = LogFactory
040                        .getLog(OnlyOnceLoggingDenyMeterFilter.class);
041
042        private final AtomicBoolean alreadyWarned = new AtomicBoolean(false);
043
044        private final Supplier<String> message;
045
046        public OnlyOnceLoggingDenyMeterFilter(Supplier<String> message) {
047                Assert.notNull(message, "Message must not be null");
048                this.message = message;
049        }
050
051        @Override
052        public MeterFilterReply accept(Id id) {
053                if (logger.isWarnEnabled() && this.alreadyWarned.compareAndSet(false, true)) {
054                        logger.warn(this.message.get());
055                }
056                return MeterFilterReply.DENY;
057        }
058
059}