mjsax commented on code in PR #14619:
URL: https://github.com/apache/kafka/pull/14619#discussion_r1374019186

##########
clients/src/main/java/org/apache/kafka/common/telemetry/internals/MetricNamingConvention.java:
##########
@@ -0,0 +1,119 @@
+/*
+ * 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.kafka.common.telemetry.internals;
+
+import org.apache.kafka.common.MetricName;
+
+import java.util.Collections;
+import java.util.Locale;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Objects;
+import java.util.regex.Pattern;
+import java.util.stream.Collectors;
+
+/**
+ * This class encapsulates naming and mapping conventions defined as part of
+ * <a 
href="https://cwiki.apache.org/confluence/display/KAFKA/KIP-714%3A+Client+metrics+and+observability#KIP714:Clientmetricsandobservability-Metricsnamingandformat";>Metrics
 naming and format</a>
+ */
+public class MetricNamingConvention {
+
+    private static final String NAME_JOINER = ".";
+    private static final String TAG_JOINER = "_";
+
+    // remove metrics as it is redundant for telemetry metrics naming 
convention
+    private final static Pattern GROUP_PATTERN = 
Pattern.compile("\\.(metrics)");
+
+    public static MetricNamingStrategy<MetricName> 
getClientTelemetryMetricNamingStrategy(String domain) {
+        return new MetricNamingStrategy<MetricName>() {
+            @Override
+            public MetricKey metricKey(MetricName metricName) {
+                Objects.requireNonNull(metricName, "metric name cannot be 
null");
+                String group = metricName.group() == null ? "" : 
metricName.group();
+                String rawName = metricName.name() == null ? "" : 
metricName.name();
+
+                return new MetricKey(fullMetricName(domain, group, rawName),
+                    Collections.unmodifiableMap(cleanTags(metricName.tags())));
+            }
+
+            @Override
+            public MetricKey derivedMetricKey(MetricKey key, String 
derivedComponent) {
+                Objects.requireNonNull(derivedComponent, "derived component 
cannot be null");
+                return new MetricKey(key.getName() + NAME_JOINER + 
derivedComponent, key.tags());
+            }
+        };
+    }
+
+    /**
+     * Creates a metric name given the domain, group, and name. The new String 
follows the following
+     * conventions and rules:
+     *
+     * <ul>
+     *   <li>domain is expected to be a host-name like value, e.g. {@code 
org.apache.kafka}</li>
+     *   <li>group is cleaned of redundant words: "-metrics"</li>
+     *   <li>the group and metric name is dot separated</li>
+     *   <li>The name is created by joining the three components, e.g.:
+     *     {@code org.apache.kafka.producer.connection.creation.rate}</li>
+     * </ul>
+     */
+    private static String fullMetricName(String domain, String group, String 
name) {
+        return domain
+            + NAME_JOINER
+            + cleanGroup(group)
+            + NAME_JOINER
+            + cleanMetric(name);
+    }
+
+    /**
+     * This method maps a raw name to follow conventions and cleans up the 
result to be more legible:
+     * <ul>
+     *  <li> converts names to lower hyphen case conventions
+     *  <li> strips redundant parts of the metric name, such as -metrics
+     *  <li> normalizes artifacts of hyphen case to dot separated conversion
+     * </ul>
+     */
+    private static String cleanGroup(String group) {
+        group = clean(group, NAME_JOINER);
+        return GROUP_PATTERN.matcher(group).replaceAll("");
+    }
+
+    private static String cleanMetric(String metric) {
+        return clean(metric, NAME_JOINER);
+    }
+
+    /**
+     * Converts a tag name to match the telemetry naming conventions by 
converting snake_case.
+     * <p>
+     * Kafka metrics have tags name in lower case separated by hyphens. Eg: 
total-errors
+     *
+     * @param raw the input map
+     * @return the new map with keys replaced by snake_case representations.
+     */
+    private static Map<String, String> cleanTags(Map<String, String> raw) {
+        return raw.entrySet()
+            .stream()
+            .collect(Collectors.toMap(s -> clean(s.getKey(), TAG_JOINER), 
Entry::getValue));
+    }
+
+    private static String clean(String raw, String joiner) {
+        Objects.requireNonNull(raw, "metric data cannot be null");
+        // Convert to lower case.

Review Comment:
   This comment is kinda point less -- it just says what the code say 
`.toLowerCase`



##########
clients/src/main/java/org/apache/kafka/common/telemetry/internals/MetricNamingConvention.java:
##########
@@ -0,0 +1,119 @@
+/*
+ * 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.kafka.common.telemetry.internals;
+
+import org.apache.kafka.common.MetricName;
+
+import java.util.Collections;
+import java.util.Locale;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Objects;
+import java.util.regex.Pattern;
+import java.util.stream.Collectors;
+
+/**
+ * This class encapsulates naming and mapping conventions defined as part of
+ * <a 
href="https://cwiki.apache.org/confluence/display/KAFKA/KIP-714%3A+Client+metrics+and+observability#KIP714:Clientmetricsandobservability-Metricsnamingandformat";>Metrics
 naming and format</a>
+ */
+public class MetricNamingConvention {
+
+    private static final String NAME_JOINER = ".";
+    private static final String TAG_JOINER = "_";
+
+    // remove metrics as it is redundant for telemetry metrics naming 
convention
+    private final static Pattern GROUP_PATTERN = 
Pattern.compile("\\.(metrics)");
+
+    public static MetricNamingStrategy<MetricName> 
getClientTelemetryMetricNamingStrategy(String domain) {
+        return new MetricNamingStrategy<MetricName>() {
+            @Override
+            public MetricKey metricKey(MetricName metricName) {
+                Objects.requireNonNull(metricName, "metric name cannot be 
null");
+                String group = metricName.group() == null ? "" : 
metricName.group();
+                String rawName = metricName.name() == null ? "" : 
metricName.name();
+
+                return new MetricKey(fullMetricName(domain, group, rawName),
+                    Collections.unmodifiableMap(cleanTags(metricName.tags())));
+            }
+
+            @Override
+            public MetricKey derivedMetricKey(MetricKey key, String 
derivedComponent) {
+                Objects.requireNonNull(derivedComponent, "derived component 
cannot be null");
+                return new MetricKey(key.getName() + NAME_JOINER + 
derivedComponent, key.tags());
+            }
+        };
+    }
+
+    /**
+     * Creates a metric name given the domain, group, and name. The new String 
follows the following
+     * conventions and rules:
+     *
+     * <ul>
+     *   <li>domain is expected to be a host-name like value, e.g. {@code 
org.apache.kafka}</li>
+     *   <li>group is cleaned of redundant words: "-metrics"</li>
+     *   <li>the group and metric name is dot separated</li>
+     *   <li>The name is created by joining the three components, e.g.:
+     *     {@code org.apache.kafka.producer.connection.creation.rate}</li>
+     * </ul>
+     */
+    private static String fullMetricName(String domain, String group, String 
name) {
+        return domain
+            + NAME_JOINER
+            + cleanGroup(group)
+            + NAME_JOINER
+            + cleanMetric(name);
+    }
+
+    /**
+     * This method maps a raw name to follow conventions and cleans up the 
result to be more legible:
+     * <ul>
+     *  <li> converts names to lower hyphen case conventions

Review Comment:
   I don't see any conversion into lower hyphen in this method?



##########
clients/src/test/java/org/apache/kafka/common/telemetry/internals/MetricNamingConventionTest.java:
##########
@@ -0,0 +1,196 @@
+/*
+ * 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.kafka.common.telemetry.internals;
+
+import org.apache.kafka.common.MetricName;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Collections;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+public class MetricNamingConventionTest {
+
+    private MetricNamingStrategy<MetricName> metricNamingStrategy;
+
+    @BeforeEach
+    public void setUp() {
+        metricNamingStrategy = MetricNamingConvention
+            .getClientTelemetryMetricNamingStrategy("org.apache.kafka");
+    }
+
+    @Test
+    public void testMetricKey() {
+        MetricName metricName = new MetricName("name", "group", "description",
+            Collections.emptyMap());
+        MetricKey metricKey = metricNamingStrategy.metricKey(metricName);
+
+        assertEquals("org.apache.kafka.group.name", metricKey.getName());
+        assertEquals(Collections.emptyMap(), metricKey.tags());
+    }
+
+    @Test
+    public void testMetricKeyWithHyphenNameAndTags() {
+        Map<String, String> tags = new HashMap<>();

Review Comment:
   Based on the test name, we should use `emptyMap` for tags in this test.



##########
clients/src/main/java/org/apache/kafka/common/telemetry/internals/MetricNamingConvention.java:
##########
@@ -0,0 +1,119 @@
+/*
+ * 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.kafka.common.telemetry.internals;
+
+import org.apache.kafka.common.MetricName;
+
+import java.util.Collections;
+import java.util.Locale;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Objects;
+import java.util.regex.Pattern;
+import java.util.stream.Collectors;
+
+/**
+ * This class encapsulates naming and mapping conventions defined as part of
+ * <a 
href="https://cwiki.apache.org/confluence/display/KAFKA/KIP-714%3A+Client+metrics+and+observability#KIP714:Clientmetricsandobservability-Metricsnamingandformat";>Metrics
 naming and format</a>
+ */
+public class MetricNamingConvention {
+
+    private static final String NAME_JOINER = ".";
+    private static final String TAG_JOINER = "_";
+
+    // remove metrics as it is redundant for telemetry metrics naming 
convention
+    private final static Pattern GROUP_PATTERN = 
Pattern.compile("\\.(metrics)");
+
+    public static MetricNamingStrategy<MetricName> 
getClientTelemetryMetricNamingStrategy(String domain) {

Review Comment:
   If this is an internal class, do we expect to pass in anything else but 
`org.apache.kafka`?



##########
clients/src/main/java/org/apache/kafka/common/telemetry/internals/MetricNamingConvention.java:
##########
@@ -0,0 +1,119 @@
+/*
+ * 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.kafka.common.telemetry.internals;
+
+import org.apache.kafka.common.MetricName;
+
+import java.util.Collections;
+import java.util.Locale;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Objects;
+import java.util.regex.Pattern;
+import java.util.stream.Collectors;
+
+/**
+ * This class encapsulates naming and mapping conventions defined as part of
+ * <a 
href="https://cwiki.apache.org/confluence/display/KAFKA/KIP-714%3A+Client+metrics+and+observability#KIP714:Clientmetricsandobservability-Metricsnamingandformat";>Metrics
 naming and format</a>
+ */
+public class MetricNamingConvention {
+
+    private static final String NAME_JOINER = ".";
+    private static final String TAG_JOINER = "_";
+
+    // remove metrics as it is redundant for telemetry metrics naming 
convention
+    private final static Pattern GROUP_PATTERN = 
Pattern.compile("\\.(metrics)");
+
+    public static MetricNamingStrategy<MetricName> 
getClientTelemetryMetricNamingStrategy(String domain) {
+        return new MetricNamingStrategy<MetricName>() {
+            @Override
+            public MetricKey metricKey(MetricName metricName) {
+                Objects.requireNonNull(metricName, "metric name cannot be 
null");
+                String group = metricName.group() == null ? "" : 
metricName.group();
+                String rawName = metricName.name() == null ? "" : 
metricName.name();
+
+                return new MetricKey(fullMetricName(domain, group, rawName),
+                    Collections.unmodifiableMap(cleanTags(metricName.tags())));
+            }
+
+            @Override
+            public MetricKey derivedMetricKey(MetricKey key, String 
derivedComponent) {
+                Objects.requireNonNull(derivedComponent, "derived component 
cannot be null");
+                return new MetricKey(key.getName() + NAME_JOINER + 
derivedComponent, key.tags());
+            }
+        };
+    }
+
+    /**
+     * Creates a metric name given the domain, group, and name. The new String 
follows the following
+     * conventions and rules:
+     *
+     * <ul>
+     *   <li>domain is expected to be a host-name like value, e.g. {@code 
org.apache.kafka}</li>
+     *   <li>group is cleaned of redundant words: "-metrics"</li>
+     *   <li>the group and metric name is dot separated</li>
+     *   <li>The name is created by joining the three components, e.g.:
+     *     {@code org.apache.kafka.producer.connection.creation.rate}</li>
+     * </ul>
+     */
+    private static String fullMetricName(String domain, String group, String 
name) {
+        return domain
+            + NAME_JOINER
+            + cleanGroup(group)
+            + NAME_JOINER
+            + cleanMetric(name);
+    }
+
+    /**
+     * This method maps a raw name to follow conventions and cleans up the 
result to be more legible:
+     * <ul>
+     *  <li> converts names to lower hyphen case conventions
+     *  <li> strips redundant parts of the metric name, such as -metrics
+     *  <li> normalizes artifacts of hyphen case to dot separated conversion
+     * </ul>
+     */
+    private static String cleanGroup(String group) {
+        group = clean(group, NAME_JOINER);
+        return GROUP_PATTERN.matcher(group).replaceAll("");
+    }
+
+    private static String cleanMetric(String metric) {
+        return clean(metric, NAME_JOINER);
+    }
+
+    /**
+     * Converts a tag name to match the telemetry naming conventions by 
converting snake_case.
+     * <p>
+     * Kafka metrics have tags name in lower case separated by hyphens. Eg: 
total-errors
+     *
+     * @param raw the input map
+     * @return the new map with keys replaced by snake_case representations.
+     */
+    private static Map<String, String> cleanTags(Map<String, String> raw) {
+        return raw.entrySet()
+            .stream()
+            .collect(Collectors.toMap(s -> clean(s.getKey(), TAG_JOINER), 
Entry::getValue));
+    }
+
+    private static String clean(String raw, String joiner) {
+        Objects.requireNonNull(raw, "metric data cannot be null");
+        // Convert to lower case.
+        String lowerCase = raw.toLowerCase(Locale.ROOT);
+        // Replace hyphens with telemetry name joiner i.e. dot.

Review Comment:
   Same



##########
clients/src/main/java/org/apache/kafka/common/telemetry/internals/MetricNamingConvention.java:
##########
@@ -0,0 +1,119 @@
+/*
+ * 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.kafka.common.telemetry.internals;
+
+import org.apache.kafka.common.MetricName;
+
+import java.util.Collections;
+import java.util.Locale;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Objects;
+import java.util.regex.Pattern;
+import java.util.stream.Collectors;
+
+/**
+ * This class encapsulates naming and mapping conventions defined as part of
+ * <a 
href="https://cwiki.apache.org/confluence/display/KAFKA/KIP-714%3A+Client+metrics+and+observability#KIP714:Clientmetricsandobservability-Metricsnamingandformat";>Metrics
 naming and format</a>
+ */
+public class MetricNamingConvention {
+
+    private static final String NAME_JOINER = ".";
+    private static final String TAG_JOINER = "_";
+
+    // remove metrics as it is redundant for telemetry metrics naming 
convention
+    private final static Pattern GROUP_PATTERN = 
Pattern.compile("\\.(metrics)");
+
+    public static MetricNamingStrategy<MetricName> 
getClientTelemetryMetricNamingStrategy(String domain) {
+        return new MetricNamingStrategy<MetricName>() {
+            @Override
+            public MetricKey metricKey(MetricName metricName) {
+                Objects.requireNonNull(metricName, "metric name cannot be 
null");
+                String group = metricName.group() == null ? "" : 
metricName.group();

Review Comment:
   It seems that `MetricName` guarantees that `group` is no null -- this check 
seems to be unnecessary. (same for `name` below)



##########
clients/src/main/java/org/apache/kafka/common/telemetry/internals/MetricNamingConvention.java:
##########
@@ -0,0 +1,119 @@
+/*
+ * 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.kafka.common.telemetry.internals;
+
+import org.apache.kafka.common.MetricName;
+
+import java.util.Collections;
+import java.util.Locale;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Objects;
+import java.util.regex.Pattern;
+import java.util.stream.Collectors;
+
+/**
+ * This class encapsulates naming and mapping conventions defined as part of
+ * <a 
href="https://cwiki.apache.org/confluence/display/KAFKA/KIP-714%3A+Client+metrics+and+observability#KIP714:Clientmetricsandobservability-Metricsnamingandformat";>Metrics
 naming and format</a>
+ */
+public class MetricNamingConvention {
+
+    private static final String NAME_JOINER = ".";
+    private static final String TAG_JOINER = "_";
+
+    // remove metrics as it is redundant for telemetry metrics naming 
convention
+    private final static Pattern GROUP_PATTERN = 
Pattern.compile("\\.(metrics)");
+
+    public static MetricNamingStrategy<MetricName> 
getClientTelemetryMetricNamingStrategy(String domain) {
+        return new MetricNamingStrategy<MetricName>() {

Review Comment:
   Should we add a null-check for `domain`?



##########
clients/src/main/java/org/apache/kafka/common/telemetry/internals/MetricNamingConvention.java:
##########
@@ -0,0 +1,119 @@
+/*
+ * 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.kafka.common.telemetry.internals;
+
+import org.apache.kafka.common.MetricName;
+
+import java.util.Collections;
+import java.util.Locale;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Objects;
+import java.util.regex.Pattern;
+import java.util.stream.Collectors;
+
+/**
+ * This class encapsulates naming and mapping conventions defined as part of
+ * <a 
href="https://cwiki.apache.org/confluence/display/KAFKA/KIP-714%3A+Client+metrics+and+observability#KIP714:Clientmetricsandobservability-Metricsnamingandformat";>Metrics
 naming and format</a>
+ */
+public class MetricNamingConvention {
+
+    private static final String NAME_JOINER = ".";
+    private static final String TAG_JOINER = "_";
+
+    // remove metrics as it is redundant for telemetry metrics naming 
convention
+    private final static Pattern GROUP_PATTERN = 
Pattern.compile("\\.(metrics)");
+
+    public static MetricNamingStrategy<MetricName> 
getClientTelemetryMetricNamingStrategy(String domain) {
+        return new MetricNamingStrategy<MetricName>() {
+            @Override
+            public MetricKey metricKey(MetricName metricName) {
+                Objects.requireNonNull(metricName, "metric name cannot be 
null");
+                String group = metricName.group() == null ? "" : 
metricName.group();
+                String rawName = metricName.name() == null ? "" : 
metricName.name();
+
+                return new MetricKey(fullMetricName(domain, group, rawName),
+                    Collections.unmodifiableMap(cleanTags(metricName.tags())));
+            }
+
+            @Override
+            public MetricKey derivedMetricKey(MetricKey key, String 
derivedComponent) {
+                Objects.requireNonNull(derivedComponent, "derived component 
cannot be null");
+                return new MetricKey(key.getName() + NAME_JOINER + 
derivedComponent, key.tags());
+            }
+        };
+    }
+
+    /**
+     * Creates a metric name given the domain, group, and name. The new String 
follows the following
+     * conventions and rules:
+     *
+     * <ul>
+     *   <li>domain is expected to be a host-name like value, e.g. {@code 
org.apache.kafka}</li>
+     *   <li>group is cleaned of redundant words: "-metrics"</li>
+     *   <li>the group and metric name is dot separated</li>
+     *   <li>The name is created by joining the three components, e.g.:
+     *     {@code org.apache.kafka.producer.connection.creation.rate}</li>
+     * </ul>
+     */
+    private static String fullMetricName(String domain, String group, String 
name) {
+        return domain
+            + NAME_JOINER
+            + cleanGroup(group)
+            + NAME_JOINER
+            + cleanMetric(name);
+    }
+
+    /**
+     * This method maps a raw name to follow conventions and cleans up the 
result to be more legible:
+     * <ul>
+     *  <li> converts names to lower hyphen case conventions
+     *  <li> strips redundant parts of the metric name, such as -metrics
+     *  <li> normalizes artifacts of hyphen case to dot separated conversion
+     * </ul>
+     */
+    private static String cleanGroup(String group) {
+        group = clean(group, NAME_JOINER);
+        return GROUP_PATTERN.matcher(group).replaceAll("");
+    }
+
+    private static String cleanMetric(String metric) {
+        return clean(metric, NAME_JOINER);
+    }
+
+    /**
+     * Converts a tag name to match the telemetry naming conventions by 
converting snake_case.

Review Comment:
   `by converting [into] snake_case.`
   
   



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