How to Upload Image stored as blob in mysql to AWS S3 bucket

Question

I have stored employee photo in MySQL table as BLOB type field with employee id. I have to migrate those blob image as image files to S3 Bucket. I am retriving InputStream object for that image in java. Now how to get extension of image and contenttype of that image. How to upload it to S3 bucket

Answer 1

I'm not sure if you can recognize image extension unless you save it to the file system since it's saved as a blob. Here is a sample code which you can use for something like this

AmazonS3 client = AmazonS3ClientBuilder.defaultClient();
    //Load the blob as a byte array
    byte [] imageData = <load the image data from db> ;// resultSet.getBytes("image");
    //create a input stream from byte array
    ByteArrayInputStream inputStream = new ByteArrayInputStream(imageData);
    //Create the buffered image from input stream
    BufferedImage image = ImageIO.read(inputStream);
    //File which you are going to save the image as
    File file = new File(String.format("$s/%s.png", folderLocation, fileName));
    //Regardless of your original image extension save the image as png as it's loseless 
    ImageIO.write(image, "PNG", file);
    //Create a s3 put request 
    PutObjectRequest request = new PutObjectRequest(bucketName, UUID.randomUUID().toString()+".png", file);
    //Upload to s3
    client.putObject(request);