BAEL-787 AWS S3 with Java (#2179)

* Files - S3 Bucket Creation and Object Upload

S3 Bucket Creation and Object Upload Using the AWS SDK for Java.
Please note. This code is not readily plug-and-play type. User needs to put his own 'access key' and 'secret key'

* S3 Bucket Creation and Object Upload-dependencies

S3 Bucket Creation and Object Upload - Adding Dependencies

* Update S3Application.java

* Update S3Application.java

* Update S3Application.java

* Fixed Test Names

* Update S3Application.java

* Added more test cases

* Added more examples

* Delete AWSS3Service.java

* Delete S3Application.java

* Added more examples

* Added more test cases

aws/pom.xml

@@ -18,9 +18,41 @@
         <aws-lambda-java-events.version>1.3.0</aws-lambda-java-events.version>
         <aws-lambda-java-core.version>1.1.0</aws-lambda-java-core.version>
         <gson.version>2.8.0</gson.version>
+        <aws-java-sdk.version>1.11.154</aws-java-sdk.version>
+        <junit.version>4.12</junit.version>
+        <mockito-core.version>2.8.9</mockito-core.version>
+        <assertj-core.version>3.8.0</assertj-core.version>
     </properties>
 
     <dependencies>
+    
+        <dependency>
+            <groupId>com.amazonaws</groupId>
+            <artifactId>aws-java-sdk</artifactId>
+            <version>${aws-java-sdk.version}</version>
+        </dependency>
+        
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>${junit.version}</version>
+            <scope>test</scope>
+        </dependency>
+        
+        <dependency>
+            <groupId>org.mockito</groupId>
+            <artifactId>mockito-core</artifactId>
+            <version>${mockito-core.version}</version>
+            <scope>test</scope>
+        </dependency>
+        
+        <dependency>
+            <groupId>org.assertj</groupId>
+            <artifactId>assertj-core</artifactId>
+            <version>${assertj-core.version}</version>
+            <scope>test</scope>
+        </dependency>
+    
         <dependency>
             <groupId>com.amazonaws</groupId>
             <artifactId>aws-lambda-java-core</artifactId>

aws/src/main/java/com/baeldung/s3/AWSS3Service.java

@@ -0,0 +1,87 @@
+package com.baeldung.s3;
+
+import java.io.File;
+import java.util.List;
+
+import com.amazonaws.services.s3.AmazonS3;
+import com.amazonaws.services.s3.AmazonS3Client;
+import com.amazonaws.services.s3.model.Bucket;
+import com.amazonaws.services.s3.model.CopyObjectResult;
+import com.amazonaws.services.s3.model.DeleteObjectsRequest;
+import com.amazonaws.services.s3.model.DeleteObjectsResult;
+import com.amazonaws.services.s3.model.ObjectListing;
+import com.amazonaws.services.s3.model.PutObjectResult;
+import com.amazonaws.services.s3.model.S3Object;
+
+public class AWSS3Service {
+    private final AmazonS3 s3client;
+
+    public AWSS3Service() { 
+        this(new AmazonS3Client() {
+        }); 
+    } 
+    
+    public AWSS3Service(AmazonS3 s3client) {
+        this.s3client = s3client;
+    }
+    
+    //is bucket exist?
+    public boolean doesBucketExist(String bucketName) { 
+        return s3client.doesBucketExist(bucketName); 
+    } 
+    
+    //create a bucket
+    public Bucket createBucket(String bucketName) { 
+        return s3client.createBucket(bucketName); 
+    } 
+
+    //list all buckets
+    public List<Bucket> listBuckets() { 
+        return s3client.listBuckets(); 
+    }
+
+    //delete a bucket
+    public void deleteBucket(String bucketName) { 
+        s3client.deleteBucket(bucketName); 
+    }  
+    
+    //uploading object
+    public PutObjectResult putObject(String bucketName, String key, File file) {
+        return s3client.putObject(bucketName, key, file);
+    }
+    
+    //listing objects
+    public ObjectListing listObjects(String bucketName) {
+        return s3client.listObjects(bucketName);
+    }
+    
+    //get an object
+    public S3Object getObject(String bucketName, String objectKey) {
+        return s3client.getObject(bucketName, objectKey);
+    } 
+    
+    //copying an object
+    public CopyObjectResult copyObject(
+      String sourceBucketName,
+      String sourceKey,
+      String destinationBucketName,
+      String destinationKey
+    ) {
+        return s3client.copyObject(
+          sourceBucketName, 
+          sourceKey, 
+          destinationBucketName, 
+          destinationKey
+        );
+    }
+    
+    //deleting an object
+    public void deleteObject(String bucketName, String objectKey) {
+        s3client.deleteObject(bucketName, objectKey);
+    }
+    
+    //deleting multiple Objects
+    public DeleteObjectsResult deleteObjects(DeleteObjectsRequest delObjReq) {
+        return s3client.deleteObjects(delObjReq);
+    }
+}

aws/src/main/java/com/baeldung/s3/S3Application.java

@@ -0,0 +1,108 @@
+package com.baeldung.s3;
+
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+
+import com.amazonaws.auth.AWSCredentials;
+import com.amazonaws.auth.AWSStaticCredentialsProvider;
+import com.amazonaws.auth.BasicAWSCredentials;
+import com.amazonaws.regions.Regions;
+import com.amazonaws.services.s3.AmazonS3;
+import com.amazonaws.services.s3.AmazonS3ClientBuilder;
+import com.amazonaws.services.s3.model.Bucket;
+import com.amazonaws.services.s3.model.DeleteObjectsRequest;
+import com.amazonaws.services.s3.model.ObjectListing;
+import com.amazonaws.services.s3.model.S3Object;
+import com.amazonaws.services.s3.model.S3ObjectInputStream;
+import com.amazonaws.services.s3.model.S3ObjectSummary;
+
+public class S3Application {
+
+    private static final AWSCredentials credentials;
+    private static String bucketName;  
+
+    static {
+        //put your accesskey and secretkey here
+        credentials = new BasicAWSCredentials(
+          "<AWS accesskey>", 
+          "<AWS secretkey>"
+        );
+    }  
+    
+    public static void main(String[] args) throws IOException {
+        //set-up the client
+        AmazonS3 s3client = AmazonS3ClientBuilder
+          .standard()
+          .withCredentials(new AWSStaticCredentialsProvider(credentials))
+          .withRegion(Regions.US_EAST_2)
+          .build();
+        
+        AWSS3Service awsService = new AWSS3Service(s3client);
+
+        bucketName = "baeldung-bucket";
+
+        //creating a bucket
+        if(awsService.doesBucketExist(bucketName)) {
+            System.out.println("Bucket name is not available."
+              + " Try again with a different Bucket name.");
+            return;
+        }
+        awsService.createBucket(bucketName);
+        
+        //list all the buckets
+        for(Bucket s : awsService.listBuckets() ) {
+            System.out.println(s.getName());
+        }
+        
+        //deleting bucket
+        awsService.deleteBucket("baeldung-bucket-test2");
+        
+        //uploading object
+        awsService.putObject(
+          bucketName, 
+          "Document/hello.txt",
+          new File("/Users/user/Document/hello.txt")
+        );
+
+        //listing objects
+        ObjectListing objectListing = awsService.listObjects(bucketName);
+        for(S3ObjectSummary os : objectListing.getObjectSummaries()) {
+            System.out.println(os.getKey());
+        }
+
+        //downloading an object
+        S3Object s3object = awsService.getObject(bucketName, "Document/hello.txt");
+        S3ObjectInputStream inputStream = s3object.getObjectContent();
+        FileOutputStream fos = new FileOutputStream(new File("/Users/user/Desktop/hello.txt"));
+
+        int read = 0;
+        byte[] bytes = new byte[1024];
+        while ((read = inputStream.read(bytes)) != -1) {
+            fos.write(bytes, 0, read);
+        }
+        inputStream.close();
+        fos.close();
+        
+        //copying an object
+        awsService.copyObject(
+          "baeldung-bucket", 
+          "picture/pic.png", 
+          "baeldung-bucket2", 
+          "Document/picture.png"
+        );
+        
+        //deleting an object
+        awsService.deleteObject(bucketName, "Document/hello.txt");
+
+        //deleting multiple objects
+        String objkeyArr[] = {
+          "Document/hello2.txt", 
+          "Document/picture.png"
+        };
+        
+        DeleteObjectsRequest delObjReq = new DeleteObjectsRequest("baeldung-bucket")
+          .withKeys(objkeyArr);
+        awsService.deleteObjects(delObjReq);
+    }
+}

aws/src/test/java/com/baeldung/s3/AWSS3ServiceIntegrationTest.java

@@ -0,0 +1,113 @@
+package com.baeldung.s3;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.anyString;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import java.io.File;
+
+import org.junit.Before;
+import org.junit.Test;
+
+import com.amazonaws.services.s3.AmazonS3;
+import com.amazonaws.services.s3.model.CopyObjectResult;
+import com.amazonaws.services.s3.model.DeleteObjectsRequest;
+import com.amazonaws.services.s3.model.DeleteObjectsResult;
+import com.amazonaws.services.s3.model.PutObjectResult; 
+
+public class AWSS3ServiceIntegrationTest {
+
+    private static final String BUCKET_NAME = "bucket_name"; 
+    private static final String KEY_NAME = "key_name"; 
+    private static final String BUCKET_NAME2 = "bucket_name2"; 
+    private static final String KEY_NAME2 = "key_name2"; 
+ 
+    private AmazonS3 s3; 
+    private AWSS3Service service; 
+ 
+    @Before 
+    public void setUp() { 
+        s3 = mock(AmazonS3.class); 
+        service = new AWSS3Service(s3); 
+    } 
+ 
+    @Test 
+    public void whenInitializingAWSS3Service_thenNotNull() { 
+        assertThat(new AWSS3Service()).isNotNull(); 
+    } 
+    
+    @Test 
+    public void whenVerifyingIfS3BucketExist_thenCorrect() { 
+        service.doesBucketExist(BUCKET_NAME); 
+        verify(s3).doesBucketExist(BUCKET_NAME); 
+    } 
+ 
+    @Test 
+    public void whenVerifyingCreationOfS3Bucket_thenCorrect() { 
+        service.createBucket(BUCKET_NAME); 
+        verify(s3).createBucket(BUCKET_NAME); 
+    } 
+ 
+    @Test 
+    public void whenVerifyingListBuckets_thenCorrect() { 
+        service.listBuckets(); 
+        verify(s3).listBuckets(); 
+    } 
+
+    @Test 
+    public void whenDeletingBucket_thenCorrect() { 
+        service.deleteBucket(BUCKET_NAME); 
+        verify(s3).deleteBucket(BUCKET_NAME); 
+    } 
+    
+    @Test 
+    public void whenVerifyingPutObject_thenCorrect() { 
+        File file = mock(File.class); 
+        PutObjectResult result = mock(PutObjectResult.class); 
+        when(s3.putObject(anyString(), anyString(), (File) any())).thenReturn(result); 
+ 
+        assertThat(service.putObject(BUCKET_NAME, KEY_NAME, file)).isEqualTo(result); 
+        verify(s3).putObject(BUCKET_NAME, KEY_NAME, file); 
+    }
+    
+    @Test 
+    public void whenVerifyingListObjects_thenCorrect() { 
+        service.listObjects(BUCKET_NAME); 
+        verify(s3).listObjects(BUCKET_NAME); 
+    } 
+    
+    @Test 
+    public void whenVerifyingGetObject_thenCorrect() { 
+        service.getObject(BUCKET_NAME, KEY_NAME); 
+        verify(s3).getObject(BUCKET_NAME, KEY_NAME); 
+    } 
+    
+    @Test 
+    public void whenVerifyingCopyObject_thenCorrect() { 
+        CopyObjectResult result = mock(CopyObjectResult.class); 
+        when(s3.copyObject(anyString(), anyString(), anyString(), anyString())).thenReturn(result); 
+ 
+        assertThat(service.copyObject(BUCKET_NAME, KEY_NAME, BUCKET_NAME2, KEY_NAME2)).isEqualTo(result); 
+        verify(s3).copyObject(BUCKET_NAME, KEY_NAME, BUCKET_NAME2, KEY_NAME2);
+    } 
+    
+    @Test 
+    public void whenVerifyingDeleteObject_thenCorrect() { 
+        service.deleteObject(BUCKET_NAME, KEY_NAME); 
+        verify(s3).deleteObject(BUCKET_NAME, KEY_NAME); 
+    }
+    
+    @Test 
+    public void whenVerifyingDeleteObjects_thenCorrect() { 
+        DeleteObjectsRequest request = mock(DeleteObjectsRequest.class);
+        DeleteObjectsResult result = mock(DeleteObjectsResult.class);
+        when(s3.deleteObjects((DeleteObjectsRequest)any())).thenReturn(result); 
+        
+        assertThat(service.deleteObjects(request)).isEqualTo(result);
+        verify(s3).deleteObjects(request); 
+    }
+    
+}