require 'aws-sdk'

AWS_KEY = {
    :aws_access_key_id => "*************",
    :aws_secret_access_key => "*************",
  }

ec2 = AWS::EC2.new(
    :access_key_id => AWS_KEY[:aws_access_key_id],
    :secret_access_key => AWS_KEY[:aws_secret_access_key])

instance = ec2.instances['i-********']

puts instance.tags['Name']

image = ec2.images.create(
      :instance_id => 'i-********',
      :name => 'test-volume-ami', 
     :block_device_mappings => {:'/dev/sda' => {:snapshot_id => 'snap-********'}})

这是段测试代码，我感觉是我 block_device_mappings 这个参数写错了，但是苦于网上找不到详细的文档，试了几次都不行，大家帮我看下是哪里出了问题