Use UploadPart with an AWS SDK

Upload part of a multipart upload for a directory bucket.

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import software.amazon.awssdk.core.sync.RequestBody;
import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.s3.S3Client;
import software.amazon.awssdk.services.s3.model.CompletedPart;
import software.amazon.awssdk.services.s3.model.S3Exception;
import software.amazon.awssdk.services.s3.model.UploadPartRequest;
import software.amazon.awssdk.services.s3.model.UploadPartResponse;

import java.io.IOException;
import java.io.RandomAccessFile;
import java.nio.ByteBuffer;
import java.nio.file.Path;
import java.util.ArrayList;
import java.util.List;

import static com.example.s3.util.S3DirectoryBucketUtils.abortDirectoryBucketMultipartUploads;
import static com.example.s3.util.S3DirectoryBucketUtils.createDirectoryBucket;
import static com.example.s3.util.S3DirectoryBucketUtils.createDirectoryBucketMultipartUpload;
import static com.example.s3.util.S3DirectoryBucketUtils.createS3Client;
import static com.example.s3.util.S3DirectoryBucketUtils.deleteAllObjectsInDirectoryBucket;
import static com.example.s3.util.S3DirectoryBucketUtils.deleteDirectoryBucket;
import static com.example.s3.util.S3DirectoryBucketUtils.getFilePath;

    /**
     * This method creates part requests and uploads individual parts to S3.
     * While it uses the UploadPart API to upload a single part, it does so
     * sequentially to handle multiple parts of a file, returning all the completed
     * parts.
     *
     * @param s3Client   The S3 client used to interact with S3
     * @param bucketName The name of the directory bucket
     * @param objectKey  The key (name) of the object to be uploaded
     * @param uploadId   The upload ID used to track the multipart upload
     * @param filePath   The path to the file to be uploaded
     * @return A list of uploaded parts
     * @throws IOException if an I/O error occurs
     */
    public static List<CompletedPart> multipartUploadForDirectoryBucket(S3Client s3Client, String bucketName,
            String objectKey, String uploadId, Path filePath) throws IOException {
        logger.info("Uploading parts for object: {} in bucket: {}", objectKey, bucketName);

        int partNumber = 1;
        List<CompletedPart> uploadedParts = new ArrayList<>();
        ByteBuffer bb = ByteBuffer.allocate(1024 * 1024 * 5); // 5 MB byte buffer

        // Read the local file, break down into chunks and process
        try (RandomAccessFile file = new RandomAccessFile(filePath.toFile(), "r")) {
            long fileSize = file.length();
            int position = 0;

            // Sequentially upload parts of the file
            while (position < fileSize) {
                file.seek(position);
                int read = file.getChannel().read(bb);

                bb.flip(); // Swap position and limit before reading from the buffer
                UploadPartRequest uploadPartRequest = UploadPartRequest.builder()
                        .bucket(bucketName)
                        .key(objectKey)
                        .uploadId(uploadId)
                        .partNumber(partNumber)
                        .build();

                UploadPartResponse partResponse = s3Client.uploadPart(
                        uploadPartRequest,
                        RequestBody.fromByteBuffer(bb));

                // Build the uploaded part
                CompletedPart uploadedPart = CompletedPart.builder()
                        .partNumber(partNumber)
                        .eTag(partResponse.eTag())
                        .build();

                // Add the uploaded part to the list
                uploadedParts.add(uploadedPart);

                // Log to indicate the part upload is done
                logger.info("Uploaded part number: {} with ETag: {}", partNumber, partResponse.eTag());

                bb.clear();
                position += read;
                partNumber++;
            }
        } catch (S3Exception e) {
            logger.error("Failed to list parts: {} - Error code: {}", e.awsErrorDetails().errorMessage(),
                    e.awsErrorDetails().errorCode());
            throw e;
        }
        return uploadedParts;
    }