From 5a06792648d7f03aeeaf78a3bec296f040e45cba Mon Sep 17 00:00:00 2001
From: Pranav Saxena <pranavsaxena@microsoft.com>
Date: Tue, 26 Mar 2024 22:34:45 -0700
Subject: [PATCH] removed ITestAbfsInputStream inheritence from
 ITestAbfsInputStreamSmallFileReads; fixed futureAwait API use; javadocs

---
 .../ITestAbfsInputStreamReadFooter.java       | 28 ++++++++++++++-----
 .../ITestAbfsInputStreamSmallFileReads.java   |  4 ++-
 2 files changed, 24 insertions(+), 8 deletions(-)

diff --git a/hadoop-tools/hadoop-azure/src/test/java/org/apache/hadoop/fs/azurebfs/services/ITestAbfsInputStreamReadFooter.java b/hadoop-tools/hadoop-azure/src/test/java/org/apache/hadoop/fs/azurebfs/services/ITestAbfsInputStreamReadFooter.java
index 7b5fe2af8407b..924f28862027c 100644
--- a/hadoop-tools/hadoop-azure/src/test/java/org/apache/hadoop/fs/azurebfs/services/ITestAbfsInputStreamReadFooter.java
+++ b/hadoop-tools/hadoop-azure/src/test/java/org/apache/hadoop/fs/azurebfs/services/ITestAbfsInputStreamReadFooter.java
@@ -25,7 +25,6 @@
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.Future;
-import java.util.concurrent.TimeUnit;
 
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.FutureDataInputStreamBuilder;
@@ -91,8 +90,6 @@ public class ITestAbfsInputStreamReadFooter extends AbstractAbfsScaleTest {
       ONE_MB
   };
 
-  private static final long FUTURE_AWAIT_TIMEOUT_SEC = 60L;
-
   private final AbfsInputStreamTestUtils abfsInputStreamTestUtils;
 
   public ITestAbfsInputStreamReadFooter() throws Exception {
@@ -121,6 +118,18 @@ public void testMultipleServerCallsAreMadeWhenTheConfIsFalse()
     validateNumBackendCalls(false);
   }
 
+
+  /**
+   * For different combination of file sizes, read buffer sizes and footer read
+   * buffer size, assert the number of server calls made when the optimization
+   * is enabled and disabled.
+   * <p>
+   * If the footer optimization is on, if the first read on the file is within the
+   * footer range (given by {@link AbfsInputStream#FOOTER_SIZE}, then the last block
+   * of size footerReadBufferSize is read from the server, and then subsequent
+   * inputStream reads from that block is returned from the buffer maintained by the
+   * AbfsInputStream. So, those reads will not result in server calls.
+   */
   private void validateNumBackendCalls(boolean optimizeFooterRead)
       throws Exception {
     int fileIdx = 0;
@@ -141,7 +150,7 @@ private void validateNumBackendCalls(boolean optimizeFooterRead)
       });
       futureList.add(future);
     }
-    FutureIO.awaitFuture(futureList, FUTURE_AWAIT_TIMEOUT_SEC, TimeUnit.SECONDS);
+    FutureIO.awaitFuture(futureList);
   }
 
   private void validateNumBackendCalls(final AzureBlobFileSystem spiedFs,
@@ -236,6 +245,11 @@ public void testSeekToEndAndReadWithConfFalse() throws Exception {
     validateSeekAndReadWithConf(false, SeekTo.END);
   }
 
+  /**
+   * For different combination of file sizes, read buffer sizes and footer read
+   * buffer size, and read from different seek positions, validate the internal
+   * state of AbfsInputStream.
+   */
   private void validateSeekAndReadWithConf(boolean optimizeFooterRead,
       SeekTo seekTo) throws Exception {
     int fileIdx = 0;
@@ -259,7 +273,7 @@ private void validateSeekAndReadWithConf(boolean optimizeFooterRead,
         }
       }));
     }
-    FutureIO.awaitFuture(futureList, FUTURE_AWAIT_TIMEOUT_SEC, TimeUnit.SECONDS);
+    FutureIO.awaitFuture(futureList);
   }
 
   private void validateSeekAndReadWithConf(final AzureBlobFileSystem spiedFs,
@@ -387,7 +401,7 @@ public void testPartialReadWithNoData() throws Exception {
           throw new RuntimeException(ex);
         }
       }));
-      FutureIO.awaitFuture(futureList, FUTURE_AWAIT_TIMEOUT_SEC, TimeUnit.SECONDS);
+      FutureIO.awaitFuture(futureList);
     }
   }
 
@@ -460,7 +474,7 @@ public void testPartialReadWithSomeData() throws Exception {
         }
       }));
     }
-    FutureIO.awaitFuture(futureList, FUTURE_AWAIT_TIMEOUT_SEC, TimeUnit.SECONDS);
+    FutureIO.awaitFuture(futureList);
   }
 
   private void validatePartialReadWithSomeData(final AzureBlobFileSystem spiedFs,
diff --git a/hadoop-tools/hadoop-azure/src/test/java/org/apache/hadoop/fs/azurebfs/services/ITestAbfsInputStreamSmallFileReads.java b/hadoop-tools/hadoop-azure/src/test/java/org/apache/hadoop/fs/azurebfs/services/ITestAbfsInputStreamSmallFileReads.java
index 3967829ee77e5..d0d5d187e4a6e 100644
--- a/hadoop-tools/hadoop-azure/src/test/java/org/apache/hadoop/fs/azurebfs/services/ITestAbfsInputStreamSmallFileReads.java
+++ b/hadoop-tools/hadoop-azure/src/test/java/org/apache/hadoop/fs/azurebfs/services/ITestAbfsInputStreamSmallFileReads.java
@@ -27,6 +27,7 @@
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.FSDataInputStream;
 import org.apache.hadoop.fs.Path;
+import org.apache.hadoop.fs.azurebfs.AbstractAbfsIntegrationTest;
 import org.apache.hadoop.fs.azurebfs.AzureBlobFileSystem;
 import org.apache.hadoop.fs.azurebfs.utils.TracingContext;
 
@@ -40,7 +41,8 @@
 import static org.apache.hadoop.fs.azurebfs.constants.FileSystemConfigurations.ONE_KB;
 import static org.apache.hadoop.fs.azurebfs.constants.FileSystemConfigurations.ONE_MB;
 
-public class ITestAbfsInputStreamSmallFileReads extends ITestAbfsInputStream {
+public class ITestAbfsInputStreamSmallFileReads extends
+    AbstractAbfsIntegrationTest {
 
   private final AbfsInputStreamTestUtils abfsInputStreamTestUtils;
   public ITestAbfsInputStreamSmallFileReads() throws Exception {