Github user zentol commented on a diff in the pull request:
https://github.com/apache/flink/pull/5857#discussion_r191174912
--- Diff:
flink-metrics/flink-metrics-prometheus/src/main/java/org/apache/flink/metrics/prometheus/AbstractPrometheusReporter.java
---
@@ -0,0 +1,283 @@
+/*
+ * 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.flink.metrics.prometheus;
+
+import org.apache.flink.annotation.PublicEvolving;
+import org.apache.flink.annotation.VisibleForTesting;
+import org.apache.flink.metrics.CharacterFilter;
+import org.apache.flink.metrics.Counter;
+import org.apache.flink.metrics.Gauge;
+import org.apache.flink.metrics.Histogram;
+import org.apache.flink.metrics.Meter;
+import org.apache.flink.metrics.Metric;
+import org.apache.flink.metrics.MetricConfig;
+import org.apache.flink.metrics.MetricGroup;
+import org.apache.flink.metrics.reporter.MetricReporter;
+import org.apache.flink.runtime.metrics.groups.AbstractMetricGroup;
+import org.apache.flink.runtime.metrics.groups.FrontMetricGroup;
+
+import io.prometheus.client.Collector;
+import io.prometheus.client.CollectorRegistry;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.AbstractMap;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Map;
+import java.util.regex.Pattern;
+
+
+/**
+ * base prometheus reporter for prometheus metrics.
+ */
+@PublicEvolving
+public abstract class AbstractPrometheusReporter implements MetricReporter
{
+
+ private static final Logger LOG =
LoggerFactory.getLogger(AbstractPrometheusReporter.class);
+
+ private static final Pattern UNALLOWED_CHAR_PATTERN =
Pattern.compile("[^a-zA-Z0-9:_]");
+ private static final CharacterFilter CHARACTER_FILTER = new
CharacterFilter() {
+ @Override
+ public String filterCharacters(String input) {
+ return replaceInvalidChars(input);
+ }
+ };
+
+ private static final char SCOPE_SEPARATOR = '_';
+ private static final String SCOPE_PREFIX = "flink" + SCOPE_SEPARATOR;
+
+ private final Map<String, AbstractMap.SimpleImmutableEntry<Collector,
Integer>> collectorsWithCountByMetricName = new HashMap<>();
+
+ @VisibleForTesting
+ static String replaceInvalidChars(final String input) {
+ // https://prometheus.io/docs/instrumenting/writing_exporters/
+ // Only [a-zA-Z0-9:_] are valid in metric names, any other
characters should be sanitized to an underscore.
+ return UNALLOWED_CHAR_PATTERN.matcher(input).replaceAll("_");
+ }
+
+ @Override
+ public abstract void open(MetricConfig config);
--- End diff --
This override is unnecessary.
---
