srowen commented on a change in pull request #25741: [WIP][SPARK-29032][CORE] Simplify Prometheus support by adding PrometheusServlet URL: https://github.com/apache/spark/pull/25741#discussion_r322755731
########## File path: core/src/main/scala/org/apache/spark/metrics/sink/PrometheusServlet.scala ########## @@ -0,0 +1,116 @@ +/* + * 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.spark.metrics.sink + +import java.util.Properties +import javax.servlet.http.HttpServletRequest + +import com.codahale.metrics.MetricRegistry +import org.eclipse.jetty.servlet.ServletContextHandler + +import org.apache.spark.{SecurityManager, SparkConf} +import org.apache.spark.ui.JettyUtils._ + +private[spark] class PrometheusServlet( + val property: Properties, + val registry: MetricRegistry, + securityMgr: SecurityManager) + extends Sink { + + val SERVLET_KEY_PATH = "path" + + val servletPath = property.getProperty(SERVLET_KEY_PATH) + + def getHandlers(conf: SparkConf): Array[ServletContextHandler] = { + Array[ServletContextHandler]( + createServletHandler(servletPath, + new ServletParams(request => getMetricsSnapshot(request), "text/plain;charset=UTF-8"), conf) + ) + } + + // The following aims to be consistent with /metrics/json result in terms of item ordering + // and with Spark JMX Sink + Prometheus JMX Converter result in terms of key/value string format. + def getMetricsSnapshot(request: HttpServletRequest): String = { + import scala.collection.JavaConverters._ + + val sb = new StringBuilder() + registry.getGauges.asScala.foreach { case (k, v) => + if (!v.getValue.isInstanceOf[String]) { + sb.append(s"${normalizeKey(k)}Value ${v.getValue}\n") + } + } + registry.getCounters.asScala.foreach { case (k, v) => + sb.append(s"${normalizeKey(k)}Count ${v.getCount}\n") + } + registry.getHistograms.asScala.foreach { case (k, h) => + val snapshot = h.getSnapshot + val prefix = normalizeKey(k) + sb.append(prefix + "Count " + h.getCount + "\n") Review comment: I guess you could use interpolation here to be consistent, but it won't matter much. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected] With regards, Apache Git Services --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
