HADOOP-19311: [ABFS] Implement Backoff and Read Footer metrics using IOStatistics Class

hadoop-tools/hadoop-azure/src/main/java/org/apache/hadoop/fs/azurebfs/AbfsCountersImpl.java

@@ -24,6 +24,7 @@
 import java.util.concurrent.atomic.AtomicLong;
 
 import org.apache.hadoop.classification.VisibleForTesting;
+import org.apache.hadoop.fs.azurebfs.services.AbfsBackoffMetrics;
 import org.apache.hadoop.fs.azurebfs.services.AbfsCounters;
 import org.apache.hadoop.fs.azurebfs.services.AbfsReadFooterMetrics;
 import org.apache.hadoop.fs.azurebfs.utils.MetricFormat;
@@ -69,6 +70,7 @@
 import static org.apache.hadoop.fs.azurebfs.AbfsStatistic.SEND_REQUESTS;
 import static org.apache.hadoop.fs.azurebfs.AbfsStatistic.SERVER_UNAVAILABLE;
 import static org.apache.hadoop.fs.azurebfs.AbfsStatistic.WRITE_THROTTLES;
+import static org.apache.hadoop.fs.azurebfs.enums.AbfsBackoffMetricsEnum.TOTAL_NUMBER_OF_REQUESTS;
 import static org.apache.hadoop.fs.statistics.impl.IOStatisticsBinding.iostatisticsStore;
 import static org.apache.hadoop.util.Time.now;
 
@@ -324,18 +326,14 @@ public DurationTracker trackDuration(String key) {
   public String toString() {
     String metric = "";
     if (abfsBackoffMetrics != null) {
-      long totalNoRequests = getAbfsBackoffMetrics().getTotalNumberOfRequests();
+      long totalNoRequests = getAbfsBackoffMetrics().getMetricValue(TOTAL_NUMBER_OF_REQUESTS);
       if (totalNoRequests > 0) {
         metric += "#BO:" + getAbfsBackoffMetrics().toString();
       }
     }
     if (abfsReadFooterMetrics != null) {
-      Map<String, AbfsReadFooterMetrics> metricsMap = getAbfsReadFooterMetrics().getMetricsMap();
-      if (metricsMap != null && !(metricsMap.isEmpty())) {
-        String readFooterMetric = getAbfsReadFooterMetrics().toString();
-        if (!readFooterMetric.equals("")) {
-          metric += "#FO:" + getAbfsReadFooterMetrics().toString();
-        }
+      if (getAbfsReadFooterMetrics().getTotalFiles() > 0 && getAbfsReadFooterMetrics().getTotalReadCount() > 0) {
+        metric += "#FO:" + getAbfsReadFooterMetrics().toString();
       }
     }
     return metric;

hadoop-tools/hadoop-azure/src/main/java/org/apache/hadoop/fs/azurebfs/constants/MetricsConstants.java

@@ -0,0 +1,37 @@
+/**
+ * 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.hadoop.fs.azurebfs.constants;
+
+import org.apache.hadoop.classification.InterfaceAudience;
+
+/**
+ * Responsible to keep all constant keys related to ABFS metrics.
+ */
+@InterfaceAudience.Private
+public final class MetricsConstants {
+    public static final String COLON = ":";
+    public static final String RETRY = "RETRY";
+    public static final String BASE = "BASE";
+    public static final String FILE = "FILE";
+
+    // Private constructor to prevent instantiation
+    private MetricsConstants() {
+        throw new AssertionError("Cannot instantiate MetricsConstants");
+    }
+}