/*
* Copyright 2012-2013 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.boot.actuate.metrics.export;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashSet;
import org.springframework.boot.actuate.metrics.Metric;
import org.springframework.boot.actuate.metrics.repository.MultiMetricRepository;
import org.springframework.boot.actuate.metrics.rich.RichGauge;
import org.springframework.boot.actuate.metrics.rich.RichGaugeReader;
import org.springframework.boot.actuate.metrics.writer.MetricWriter;
import org.springframework.boot.actuate.metrics.writer.PrefixMetricWriter;
/**
* Exporter or converter for {@link RichGauge} data to a metric-based back end. Each gauge
* measurement is stored as a set of related metrics with a common prefix (the name of the
* gauge), and suffixes that describe the data. For example, a gauge called
* <code>foo</code> is stored as
* <code>[foo.min, foo.max. foo.val, foo.count, foo.avg, foo.alpha]</code>. If the
* {@link MetricWriter} provided is a {@link MultiMetricRepository} then the values for a
* gauge will be stored as a group, and hence will be retrievable from the repository in a
* single query (or optionally individually).
*
* @author Dave Syer
*/
public class RichGaugeExporter extends AbstractMetricExporter {
private static final String MIN = ".min";
private static final String MAX = ".max";
private static final String COUNT = ".count";
private static final String VALUE = ".val";
private static final String AVG = ".avg";
private static final String ALPHA = ".alpha";
private final RichGaugeReader reader;
private final PrefixMetricWriter writer;
public RichGaugeExporter(RichGaugeReader reader, PrefixMetricWriter writer) {
this(reader, writer, "");
}
public RichGaugeExporter(RichGaugeReader reader, PrefixMetricWriter writer,
String prefix) {
super(prefix);
this.reader = reader;
this.writer = writer;
}
@Override
protected Iterable<Metric<?>> next(String group) {
RichGauge rich = this.reader.findOne(group);
Collection<Metric<?>> metrics = new ArrayList<Metric<?>>();
metrics.add(new Metric<Number>(group + MIN, rich.getMin()));
metrics.add(new Metric<Number>(group + MAX, rich.getMax()));
metrics.add(new Metric<Number>(group + COUNT, rich.getCount()));
metrics.add(new Metric<Number>(group + VALUE, rich.getValue()));
metrics.add(new Metric<Number>(group + AVG, rich.getAverage()));
metrics.add(new Metric<Number>(group + ALPHA, rich.getAlpha()));
return metrics;
}
@Override
protected Iterable<String> groups() {
Collection<String> names = new HashSet<String>();
for (RichGauge rich : this.reader.findAll()) {
names.add(rich.getName());
}
return names;
}
@Override
protected void write(String group, Collection<Metric<?>> values) {
this.writer.set(group, values);
}
}