zipkin2.server.internal.prometheus.ZipkinMetricsController Maven / Gradle / Ivy

Go to download
/*
 * Copyright 2015-2019 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 zipkin2.server.internal.prometheus;

import com.fasterxml.jackson.databind.node.JsonNodeFactory;
import com.fasterxml.jackson.databind.node.ObjectNode;
import com.linecorp.armeria.server.annotation.Get;
import com.linecorp.armeria.server.annotation.ProducesJson;
import io.micrometer.core.instrument.Counter;
import io.micrometer.core.instrument.Gauge;
import io.micrometer.core.instrument.Meter;
import io.micrometer.core.instrument.MeterRegistry;
import io.prometheus.client.CollectorRegistry;

public class ZipkinMetricsController {
  final MeterRegistry meterRegistry;
  final CollectorRegistry collectorRegistry;
  final JsonNodeFactory factory = JsonNodeFactory.instance;

  ZipkinMetricsController(MeterRegistry meterRegistry, CollectorRegistry collectorRegistry) {
    this.meterRegistry = meterRegistry;
    this.collectorRegistry = collectorRegistry;
  }

  // Extracts Zipkin metrics to provide backward compatibility
  @Get("/metrics")
  @ProducesJson
  public ObjectNode fetchMetricsFromMicrometer() {
    ObjectNode metricsJson = factory.objectNode();
    // Get the Zipkin Custom meters for constructing the Metrics endpoint
    for (Meter meter : meterRegistry.getMeters()) {
      String name = meter.getId().getName();
      if (!name.startsWith("zipkin_collector")) continue;
      String transport = meter.getId().getTag("transport");
      if (transport == null) continue;

      Meter.Type type = meter.getId().getType();
      if (type == Meter.Type.COUNTER) {
        metricsJson.put("counter." + name + "." + transport, ((Counter) meter).count());
      } else if (type == Meter.Type.GAUGE) {
        metricsJson.put("gauge." + name + "." + transport, ((Gauge) meter).value());
      } // We only use counters and gauges
    }
    return metricsJson;
  }
}