PutObjectFromStreamAsync.java

// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0
package com.example.s3.async;

// snippet-start:[s3.java2.async_stream.complete]
// snippet-start:[s3.java2.async_stream.import]
import com.example.s3.util.AsyncExampleUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import software.amazon.awssdk.core.async.AsyncRequestBody;
import software.amazon.awssdk.core.async.BlockingInputStreamAsyncRequestBody;
import software.amazon.awssdk.core.exception.SdkException;
import software.amazon.awssdk.services.s3.S3AsyncClient;
import software.amazon.awssdk.services.s3.model.PutObjectResponse;

import java.io.ByteArrayInputStream;
import java.util.UUID;
import java.util.concurrent.CompletableFuture;
// snippet-end:[s3.java2.async_stream.import]

public class PutObjectFromStreamAsync {
    private static final Logger logger = LoggerFactory.getLogger(PutObjectFromStreamAsync.class);


    public static void main(String[] args) {
        String bucketName = "x-" + UUID.randomUUID();
        String key = UUID.randomUUID().toString();

        AsyncExampleUtils.createBucket(bucketName);
        try {
            PutObjectFromStreamAsync example = new PutObjectFromStreamAsync();
            PutObjectResponse putObjectResponse = example.putObjectFromStream(AsyncExampleUtils.client, bucketName, key);
            logger.info("Object {} etag: {}", key, putObjectResponse.eTag());
            logger.info("Object {} uploaded to bucket {}.", key, bucketName);
        } catch (SdkException e) {
            logger.error(e.getMessage(), e);
        } finally {
            AsyncExampleUtils.deleteObject(bucketName, key);
            AsyncExampleUtils.deleteBucket(bucketName);
        }
    }

// snippet-start:[s3.java2.async_stream.main]
    /**
     * @param s33CrtAsyncClient - To upload content from a stream of unknown size, use the AWS CRT-based S3 client. For more information, see
     *                          https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/crt-based-s3-client.html.
     * @param bucketName - The name of the bucket.
     * @param key - The name of the object.
     * @return software.amazon.awssdk.services.s3.model.PutObjectResponse - Returns metadata pertaining to the put object operation.
     */
    public PutObjectResponse putObjectFromStream(S3AsyncClient s33CrtAsyncClient, String bucketName, String key) {

        BlockingInputStreamAsyncRequestBody body =
                AsyncRequestBody.forBlockingInputStream(null); // 'null' indicates a stream will be provided later.

        CompletableFuture<PutObjectResponse> responseFuture =
                s33CrtAsyncClient.putObject(r -> r.bucket(bucketName).key(key), body);

        // AsyncExampleUtils.randomString() returns a random string up to 100 characters.
        String randomString = AsyncExampleUtils.randomString();
        logger.info("random string to upload: {}: length={}", randomString, randomString.length());

        // Provide the stream of data to be uploaded.
        body.writeInputStream(new ByteArrayInputStream(randomString.getBytes()));

        PutObjectResponse response = responseFuture.join(); // Wait for the response.
        logger.info("Object {} uploaded to bucket {}.", key, bucketName);
        return response;
    }
}
// snippet-end:[s3.java2.async_stream.main]
// snippet-end:[s3.java2.async_stream.complete]