Added test util for state build verification

ambry-server/src/main/java/com/github/ambry/server/AmbryServer.java

@@ -507,7 +507,8 @@ public void startup() throws InstantiationException {
       testE2EFlow();
       logger.info("Demo: E2E flow took {} ms", System.currentTimeMillis() - startTimeMs);
 
-//      testChunkAggregateWithStateBuildForFileCopy();
+      testFileChunkAggregationForFileCopy();
+      testStateBuildPostFileCopy();
 //      testFileStoreUtils();
     } catch (Exception e) {
       logger.error("Error during startup", e);
@@ -594,12 +595,13 @@ private void testFileStoreUtils() throws StoreException, IOException {
     System.out.println("Parsed log file contents read for offset=" + offset + ", size=" + size + " is: " + StandardCharsets.UTF_8.decode(byteBuffer));
   }
 
-  private void testChunkAggregateWithStateBuildForFileCopy() throws IOException {
-    String partitionName = "0";
+  private void testFileChunkAggregationForFileCopy() throws IOException {
     String chunkPath = "/tmp/0/test_chunk";     // The path to the chunk file
     String logFilePath = "/tmp/0/0_log";        // The path to the log file where chunks are written
     String outputFilePath = "/tmp/0/output_log_copy"; // New file where the log data will be copied
 
+    System.out.println("Testing file chunk aggregation for filecopy with Filestore");
+
     int numChunksToWrite = 10;   // Number of times the chunk should be written to the log file
     int chunkSize = (int)Files.size(Paths.get(chunkPath));  // Size of the chunk
 
@@ -625,6 +627,44 @@ private void testChunkAggregateWithStateBuildForFileCopy() throws IOException {
     }
 
 
+    // Step 2: Read from logFilePath chunk by chunk and write to a new file in the same directory
+    int offset = 0;
+    try (FileInputStream logInputStream = new FileInputStream(logFilePath);
+        FileOutputStream outputStream = new FileOutputStream(outputFilePath)) {
+
+      byte[] buffer = new byte[chunkSize];
+      int bytesRead;
+      while ((bytesRead = logInputStream.read(buffer)) != -1) {
+        // Write the chunk to the new file
+        outputStream.write(buffer, 0, bytesRead);
+        offset += bytesRead;
+
+        System.out.println("Writing chunk to new file at offset " + offset);
+      }
+
+      // Verify if contents of both files are same
+      byte[] content1 = Files.readAllBytes(Paths.get(logFilePath));
+      byte[] content2 = Files.readAllBytes(Paths.get(outputFilePath));
+      // Compare the byte arrays
+      if (Arrays.equals(content1, content2)) {
+        System.out.println("Input and output files are identical.");
+      } else {
+        System.out.println("Input and output files differ.");
+      }
+      System.out.println("File copy completed. Data written to " + outputFilePath);
+    } catch (IOException e) {
+      System.err.println("An error occurred while reading or writing the log file: " + e.getMessage());
+    }
+  }
+
+
+  private void testStateBuildPostFileCopy() throws IOException {
+    String partitionName = "803";
+    String logFilePath = "/tmp/803/14_0_log";        // The path to the log file where chunks are written
+    String outputFilePath = "/tmp/803/15_0_log"; // New file where the log data will be copied
+    int chunkSize = 100*1024*1024;  // Size of the chunk
+    System.out.println("Testing state build post filecopy for partitionId " + partitionName);
+
     // Step 2: Read from logFilePath chunk by chunk and write to a new file in the same directory
     int offset = 0;
     try (FileInputStream logInputStream = new FileInputStream(logFilePath);
@@ -660,8 +700,10 @@ private void testChunkAggregateWithStateBuildForFileCopy() throws IOException {
     // rename the output file to act as the new base log file
     Files.move(Paths.get(outputFilePath), Paths.get(logFilePath));
 
-    storageManager.buildStateForFileCopy(storageManager.getReplica(partitionName));
+    System.out.println("Renamed log file: " + outputFilePath + " to " + logFilePath );
 
+    storageManager.buildStateForFileCopy(storageManager.getReplica(partitionName));
+    System.out.println("State build successfully for partitionId: " + partitionName);
   }
 
   /**