TIL: How to control files on S3 from Ruby SDK

s3.md

s3 = Aws::S3::Client.new(
  access_key_id: <>,
  secret_access_key: <>,
  region: <>,
)

Create a directory

Amazon S3 has a flat structure with no hierarchy like you would see in a file system. However, you can create a directory structure. https://docs.aws.amazon.com/AmazonS3/latest/user-guide/using-folders.html

s3.bucket(<bucket name>).object("directory1/text1.txt").put(body: "<text1.txt's content>")

Download a image

# with Class: Aws::S3::Resource

File.open('filename', 'wb') do |file|
  s3.bucket('bucket-name').object('object-key').get(response_target: file)
end

# with Class: Aws::S3::Client

File.open('filename', 'wb') do |file|
  s3.get_object({ bucket:'bucket-name', key:'object-key'}, target: file)
end

• https://aws.amazon.com/jp/blogs/developer/downloading-objects-from-amazon-s3-using-the-aws-sdk-for-ruby/