Ruby

require "aws-sdk-s3"

# Wraps Amazon S3 bucket actions.
class BucketCreateWrapper
  attr_reader :bucket

  # @param bucket [Aws::S3::Bucket] An Amazon S3 bucket initialized with a name.
  def initialize(bucket)
    @bucket = bucket
  end

  # Creates an Amazon S3 bucket in the specified AWS Region.
  #
  # @param region [String] The Region where the bucket is created.
  # @return [Boolean] True when the bucket is created; otherwise, false.
  def create?(region)
    @bucket.create(create_bucket_configuration: { location_constraint: region })
    true
  rescue Aws::Errors::ServiceError => e
    puts "Couldn't create bucket. Here's why: #{e.message}"
    false
  end

  # Gets the Region where the bucket is located.
  #
  # @return [String] The location of the bucket.
  def location
    if @bucket.nil?
      "None. You must create a bucket before you can get its location!"
    else
      @bucket.client.get_bucket_location(bucket: @bucket.name).location_constraint
    end
  rescue Aws::Errors::ServiceError => e
    "Couldn't get the location of #{@bucket.name}. Here's why: #{e.message}"
  end
end

def run_demo
  region = "us-east-2"
  Aws.config.update(
    endpoint:  'http://s3.localhost.localstack.cloud:4566', # update with localstack endpoint
    access_key_id: 'test', # update with localstack credentials
    secret_access_key: 'test', # update with localstack credentials
    region: region,
    force_path_style: true, # Enable 'force_path_style' => true, if bucket name is non DNS compliant
  )
  bucket_name = "doc-example-bucket-#{SecureRandom.uuid}"
  wrapper = BucketCreateWrapper.new(Aws::S3::Bucket.new(bucket_name))
  return unless wrapper.create?(region)

  puts "Created bucket #{wrapper.bucket.name}."
  puts "Your bucket's region is: #{wrapper.location}"
end

run_demo if $PROGRAM_NAME == __FILE__

$ ruby ./localstack.rb                                                                                                        
Created bucket doc-example-bucket-b911f85f-4dd3-4668-a32e-3f69aa4e37dc.
Your bucket's region is: us-east-2

region = "us-east-2"
Aws.config.update(
    endpoint:  'http://localhost:4566', # update with localstack endpoint
    access_key_id: 'test', # update with localstack credentials
    secret_access_key: 'test', # update with localstack credentials
    region: region,
)