fix(authority): Close input stream on s3 file read (#359)

* fix(authority): Close inpputstream on s3 file read

Closes: MODELINKS-278

NEWS.md

@@ -14,6 +14,7 @@
 
 ### Bug fixes
 * Fix context mix-up on data propagation ([MODELINKS-273](https://folio-org.atlassian.net/browse/MODELINKS-273))
+* Close input stream on s3 file read ([MODELINKS-278](https://folio-org.atlassian.net/browse/MODELINKS-278))
 
 ### Tech Dept
 * Add missing interface `source-storage-batch` dependency in module descriptor ([MODELINKS-275](https://folio-org.atlassian.net/browse/MODELINKS-275))

src/main/java/org/folio/entlinks/service/authority/BulkAuthorityS3Client.java

@@ -1,6 +1,7 @@
 package org.folio.entlinks.service.authority;
 
 import java.io.BufferedReader;
+import java.io.IOException;
 import java.io.InputStreamReader;
 import java.util.List;
 import lombok.RequiredArgsConstructor;
@@ -10,6 +11,9 @@
 import org.springframework.retry.annotation.Retryable;
 import org.springframework.stereotype.Component;
 
+/**
+ * Code partially generated using GitHub Copilot.
+ * */
 @Log4j2
 @Component
 @RequiredArgsConstructor
@@ -23,10 +27,13 @@ public class BulkAuthorityS3Client {
     backoff = @Backoff(delayExpression = "${folio.remote-storage.retryDelayMs}"))
   public List<String> readFile(String remoteFileName) {
     log.info("readFile::Reading lines from the file [filename: {}]", remoteFileName);
-    var inputStream = s3Client.read(remoteFileName);
-    return new BufferedReader(new InputStreamReader(inputStream))
-      .lines()
-      .toList();
+    try (var inputStream = s3Client.read(remoteFileName);
+         var reader = new BufferedReader(new InputStreamReader(inputStream))) {
+      return reader.lines().toList();
+    } catch (IOException e) {
+      log.error("readFile::Error reading file [filename: {}]", remoteFileName, e);
+      throw new IllegalStateException("Error reading file: " + remoteFileName, e);
+    }
   }
 
   @Retryable(

src/test/java/org/folio/entlinks/service/authority/BulkAuthorityS3ClientTest.java

@@ -2,6 +2,7 @@
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
@@ -15,6 +16,9 @@
 import org.mockito.Mock;
 import org.mockito.junit.jupiter.MockitoExtension;
 
+/**
+ * Code partially generated using GitHub Copilot.
+ * */
 @UnitTest
 @ExtendWith(MockitoExtension.class)
 class BulkAuthorityS3ClientTest {
@@ -42,6 +46,33 @@ void readFile_ReturnsListOfStringAuthority() {
     assertThat(stringAuthority).contains(AUTHORITY_UUID, "Test Authority");
   }
 
+  @Test
+  void readFile_ReturnsEmptyListWhenFileIsEmpty() {
+    // Arrange
+    var remoteFileName = "empty-file";
+    var inputStream = new ByteArrayInputStream(new byte[0]);
+    when(s3Client.read(remoteFileName)).thenReturn(inputStream);
+
+    // Act
+    var resultList = client.readFile(remoteFileName);
+
+    // Assert
+    assertThat(resultList).isEmpty();
+  }
+
+  @Test
+  void readFile_ThrowsIllegalStateExceptionWhenIoExceptionOccurs() {
+    // Arrange
+    var remoteFileName = "error-file";
+    when(s3Client.read(remoteFileName)).thenAnswer(invocation -> {
+      throw new IOException("Test IOException");
+    });
+
+    // Act & Assert
+    var exception = assertThrows(IllegalStateException.class, () -> client.readFile(remoteFileName));
+    assertThat(exception).hasMessageContaining("Error reading file: " + remoteFileName);
+  }
+
   @Test
   void uploadErrorFiles_uploads() throws IOException {
     // Arrange