Polish MongoDB binder changes (#3099)

Author: izeye

micrometer-binders/src/main/java/io/micrometer/binder/mongodb/DefaultMongoCommandTagsProvider.java

@@ -36,11 +36,11 @@ public class DefaultMongoCommandTagsProvider implements MongoCommandTagsProvider
 
     private static final WarnThenDebugLogger WARN_THEN_DEBUG_LOGGER = new WarnThenDebugLogger(DefaultMongoCommandTagsProvider.class);
 
-    private final ConcurrentMap<Integer, MongoCommandStartedEventTags> inFlightCommandStartedEventTags = new ConcurrentHashMap<>();
+    private final ConcurrentMap<Integer, MongoCommandStartedEventTags> inFlightCommandStartedEventTagsByRequestId = new ConcurrentHashMap<>();
 
     @Override
     public Iterable<Tag> commandTags(CommandEvent event) {
-        Optional<MongoCommandStartedEventTags> mongoCommandStartedEventTags = Optional.ofNullable(inFlightCommandStartedEventTags.remove(event.getRequestId()));
+        Optional<MongoCommandStartedEventTags> mongoCommandStartedEventTags = Optional.ofNullable(inFlightCommandStartedEventTagsByRequestId.remove(event.getRequestId()));
         return Tags.of(
                 Tag.of("command", event.getCommandName()),
                 Tag.of("database", mongoCommandStartedEventTags.map(MongoCommandStartedEventTags::getDatabase).orElse("unknown")),
@@ -53,12 +53,12 @@ public Iterable<Tag> commandTags(CommandEvent event) {
     @Override
     public void commandStarted(CommandStartedEvent event) {
         MongoCommandStartedEventTags tags = new MongoCommandStartedEventTags(event);
-        addTagsForStartedCommandEvent(event, tags);
+        addTagsForCommandStartedEvent(event, tags);
     }
 
-    private void addTagsForStartedCommandEvent(CommandEvent event, MongoCommandStartedEventTags tags) {
-        if (inFlightCommandStartedEventTags.size() < 1000) {
-            inFlightCommandStartedEventTags.put(event.getRequestId(), tags);
+    private void addTagsForCommandStartedEvent(CommandEvent event, MongoCommandStartedEventTags tags) {
+        if (inFlightCommandStartedEventTagsByRequestId.size() < 1000) {
+            inFlightCommandStartedEventTagsByRequestId.put(event.getRequestId(), tags);
             return;
         }
         // Cache over capacity

micrometer-binders/src/main/java/io/micrometer/binder/mongodb/MongoCommandStartedEventTags.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2021 VMware, Inc.
+ * Copyright 2022 VMware, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -33,22 +33,22 @@ class MongoCommandStartedEventTags {
             "aggregate", "count", "distinct", "mapReduce", "geoSearch", "delete", "find", "findAndModify",
             "insert", "update", "collMod", "compact", "convertToCapped", "create", "createIndexes", "drop",
             "dropIndexes", "killCursors", "listIndexes", "reIndex"));
-    public static final String UNKNOWN = "unknown";
+    private static final String UNKNOWN = "unknown";
 
-    public MongoCommandStartedEventTags(CommandStartedEvent event) {
+    private final String collection;
+    private final String database;
+
+    MongoCommandStartedEventTags(CommandStartedEvent event) {
         this.database = event.getDatabaseName();
-        this.collection = this.determineCollectionName(event.getCommandName(), event.getCommand())
+        this.collection = determineCollectionName(event.getCommandName(), event.getCommand())
                 .orElse(UNKNOWN);
     }
 
-    private final String collection;
-    private final String database;
-
-    public String getDatabase() {
+    String getDatabase() {
         return database;
     }
 
-    public String getCollection() {
+    String getCollection() {
         return collection;
     }
 

micrometer-binders/src/test/java/io/micrometer/binder/mongodb/MongoCommandStartedEventTagsTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2021 VMware, Inc.
+ * Copyright 2022 VMware, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.