AWS SNS publish api curl request

request.rb

require 'json'
require 'aws-sigv4'
require 'active_support/core_ext'

params = {
  'Action' => 'Publish',
  'TargetArn' => 'arn:aws:sns:ap-northeast-1:000000000000:example-topic',
  'Message' => 'message',
  'Version' => '2010-03-31'
}.to_query

signer = Aws::Sigv4::Signer.new(
 service: 'sns',
 region: 'ap-northeast-1',
 access_key_id: ENV['AWS_ACCESS_KEY_ID'],
 secret_access_key: ENV['AWS_SECRET_ACCESS_KEY'],
 session_token: ENV['AWS_SESSION_TOKEN'] # use STS
)

signature = signer.sign_request(
 http_method: 'GET',
 url: 'https://sns.ap-northeast-1.amazonaws.com/?' + params
)

cmd = <<EOS
curl -X GET \
 -H 'host: #{signature.headers['host']}' \
 -H 'x-amz-content-sha256: #{signature.headers['x-amz-content-sha256']}' \
 -H 'x-amz-date: #{signature.headers['x-amz-date']}' \
 -H 'x-amz-security-token: #{signature.headers['x-amz-security-token']}' \
 -H 'authorization: #{signature.headers['authorization']}' \
'https://sns.ap-northeast-1.amazonaws.com/?#{params}'
EOS

puts cmd
puts system(cmd)