Test Class

package com.blinkai.server.service;

import static com.amazonaws.services.s3.model.CannedAccessControlList.PublicRead;
import static com.blinkai.server.util.Constants.S3_BUCKET_NAME;
import static com.blinkai.server.util.StringUtils.isEmpty;
import static org.mockito.ArgumentMatchers.any;
import static org.mockito.ArgumentMatchers.eq;
import static org.mockito.Mockito.doReturn;
import static org.mockito.Mockito.doThrow;
import static org.mockito.Mockito.times;
import static org.mockito.Mockito.verify;
import static org.testng.Assert.assertEquals;
import static org.testng.Assert.assertFalse;
import static org.testng.Assert.assertNotNull;
import static org.testng.Assert.assertNull;
import static org.testng.Assert.assertTrue;

import com.amazonaws.services.s3.AmazonS3;
import com.amazonaws.services.s3.model.PutObjectRequest;
import com.amazonaws.services.s3.transfer.MultipleFileDownload;
import com.amazonaws.services.s3.transfer.TransferManager;
import java.io.File;
import org.mockito.ArgumentCaptor;
import org.mockito.Mock;
import org.mockito.MockitoAnnotations;
import org.mockito.Spy;
import org.testng.annotations.BeforeMethod;
import org.testng.annotations.Test;

public class AWSServiceTest {

  @Mock
  private AmazonS3 client;

  @Mock
  private TransferManager transferManager;

  @Mock
  private MultipleFileDownload multipleFileDownload;

  @Spy
  private AWSService awsService;

  @BeforeMethod
  public void init() {
    MockitoAnnotations.initMocks(this);
    doReturn(client).when(awsService).getClient();
    doReturn(transferManager).when(awsService).getTransferManager();
    doReturn(multipleFileDownload).when(transferManager).downloadDirectory(any(), any(), any());
  }

//  @Test
  public void uploadImage_CallsPutObjectWithPublicReadAccess() {
    awsService.secretKey = null;
    awsService.accessKey = null;
    assertNotNull(awsService);
    String result = awsService.uploadImage("/tmp/abc.jpg", "profile/abc.jpg");
    assertNotNull(result);
    assertTrue(!isEmpty(result));
    ArgumentCaptor<PutObjectRequest> putObjectRequestArgumentCaptor = ArgumentCaptor
        .forClass(PutObjectRequest.class);
    verify(client, times(1)).putObject(putObjectRequestArgumentCaptor.capture());

    PutObjectRequest request = putObjectRequestArgumentCaptor.getValue();
    assertNotNull(request);
    assertEquals(request.getCannedAcl(), PublicRead);
    assertEquals(request.getBucketName(), S3_BUCKET_NAME);
    assertEquals(request.getFile().getPath(), "/tmp/abc.jpg");
    assertEquals(request.getKey(), "profile/abc.jpg");
  }

//  @Test
  public void uploadImage_CallsPutObjectWithSetContentType() {
    awsService.secretKey = null;
    awsService.accessKey = null;
    assertNotNull(awsService);
    String result = awsService.uploadImage("/tmp/abc.jpg", "profile/abc.jpg", "application/xml");
    assertNotNull(result);
    assertTrue(!isEmpty(result));
    ArgumentCaptor<PutObjectRequest> putObjectRequestArgumentCaptor = ArgumentCaptor
        .forClass(PutObjectRequest.class);
    verify(client, times(1)).putObject(putObjectRequestArgumentCaptor.capture());

    PutObjectRequest request = putObjectRequestArgumentCaptor.getValue();
    assertNotNull(request);
    assertEquals(request.getMetadata().getContentType(), "application/xml");
    assertEquals(request.getCannedAcl(), PublicRead);
  }

//  @Test
  public void uploadImage_CallsPutObjectWithoutSettingContentType() {
    awsService.secretKey = null;
    awsService.accessKey = null;
    assertNotNull(awsService);
    String result = awsService.uploadImage("/tmp/abc.jpg", "profile/abc.jpg", null);
    assertNotNull(result);
    assertTrue(!isEmpty(result));
    ArgumentCaptor<PutObjectRequest> putObjectRequestArgumentCaptor = ArgumentCaptor
        .forClass(PutObjectRequest.class);
    verify(client, times(1)).putObject(putObjectRequestArgumentCaptor.capture());

    PutObjectRequest request = putObjectRequestArgumentCaptor.getValue();
    assertNotNull(request);
    assertNull(request.getMetadata().getContentType());
    assertEquals(request.getCannedAcl(), PublicRead);
  }

  @Test
  public void downloadDirectory_passesCorrectArgumentsToDownloadPath() {
    awsService.secretKey = null;
    awsService.accessKey = null;
    assertNotNull(awsService);
    File destination = new File("/tmp");
    boolean result = awsService.downloadDirectory("store/abc123/pass/", destination);
    assertTrue(result);
    verify(transferManager, times(1))
        .downloadDirectory(eq(S3_BUCKET_NAME), eq("store/abc123/pass/"), eq(destination));
  }

  @Test
  public void downloadDirectory_returnsFalseIfInterruptionException() throws InterruptedException {
    awsService.secretKey = null;
    awsService.accessKey = null;
    assertNotNull(awsService);
    File destination = new File("/tmp");
    doThrow(new InterruptedException("Test Interruption thrown")).when(multipleFileDownload)
        .waitForCompletion();
    boolean result = awsService.downloadDirectory("store/abc123/pass/", destination);
    assertFalse(result);
  }
}