Add method S3Operations#createResource. (awspring#1223)

Fixes awspring#1023

spring-cloud-aws-s3/src/main/java/io/awspring/cloud/s3/S3Operations.java

@@ -100,6 +100,18 @@ public interface S3Operations {
  */
  S3Resource store(String bucketName, String key, Object object);
 
+ /**
+ * Creates an {@link S3Resource} for given bucket name and object key using {@link S3OutputStreamProvider}
+ * configured on the implementation class ({@link S3Template}).
+ * <p>
+ * Note that calling this method does not create an actual object on S3.
+ *
+ * @param bucketName - the bucket name
+ * @param key - the object key
+ * @return the {@link S3Resource}
+ */
+ S3Resource createResource(String bucketName, String key);
+
  /**
  * Reads a Java object from a S3 bucket. Uses {@link S3ObjectConverter} for deserialization.
  *

spring-cloud-aws-s3/src/main/java/io/awspring/cloud/s3/S3Template.java

@@ -140,6 +140,11 @@ public S3Resource store(String bucketName, String key, Object object) {
  return new S3Resource(bucketName, key, s3Client, s3OutputStreamProvider);
  }
 
+ @Override
+ public S3Resource createResource(String bucketName, String key) {
+ return new S3Resource(bucketName, key, s3Client, s3OutputStreamProvider);
+ }
+
  @Override
  public <T> T read(String bucketName, String key, Class<T> clazz) {
  Assert.notNull(bucketName, "bucketName is required");

spring-cloud-aws-s3/src/test/java/io/awspring/cloud/s3/S3TemplateTests.java

@@ -18,6 +18,7 @@
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
 
@@ -77,4 +78,17 @@ void throwsExceptionWhenReadFails() {
  });
  }
 
+ @Test
+ void createsS3Resource() throws IOException {
+ S3OutputStream outputStream = mock(S3OutputStream.class);
+ when(s3OutputStreamProvider.create(eq("bucket"), eq("key"), any())).thenReturn(outputStream);
+
+ S3Resource resource = s3Template.createResource("bucket", "key");
+
+ assertThat(resource).isNotNull();
+ assertThat(resource.getOutputStream()).isEqualTo(outputStream);
+ assertThat(resource.getLocation().getBucket()).isEqualTo("bucket");
+ assertThat(resource.getLocation().getObject()).isEqualTo("key");
+ }
+
 }