convert s3 endpoint to region

convert_s3endpoint_to_region.rb

# Convert s3-endpoint to region name
# http://docs.aws.amazon.com/general/latest/gr/rande.html#s3_region
def self.endpoint_to_region(endpoint)
  case endpoint.to_s
  when ''
    nil
  when 's3.amazonaws.com', 's3-external-1.amazonaws.com'
    'us-east-1'
  when 's3-us-west-2.amazonaws.com'
    'us-west-2'
  when 's3-us-west-1.amazonaws.com'
    'us-west-1'
  when 's3-eu-west-1.amazonaws.com'
    'eu-west-1'
  when 's3.eu-central-1.amazonaws.com', 's3-eu-central-1.amazonaws.com'
    'eu-central-1'
  when 's3-ap-southeast-1.amazonaws.com'
    'ap-southeast-1'
  when 's3-ap-southeast-2.amazonaws.com'
    'ap-southeast-2'
  when 's3-ap-northeast-1.amazonaws.com'
    'ap-northeast-1'
  when 's3-sa-east-1.amazonaws.com'
    'sa-east-1'
  else
    raise "Unsupported s3-endpoint:#{endpoint}"
  end
end