fake_kms_client.rb

# frozen_string_literal: true

require 'aws_kms_client'

# Client that interfaces with the AWS KMS API
class FakeKmsClient < AwsKmsClient
  class << self
    def iv
      'o' * 12
    end

    def key
      'a' * 32
    end

    def encrypted_kms_key_fixture
      Base64.encode64([FakeKmsClient.key].pack('H*'))
    end
  end

  def initialize(opts = {})
    @default_key_id = 'key'
    @key_spec = 'AES-256'
    @client = Aws::KMS::Client.new(stub_responses: stubs)
  end

  private
    def stubs
      {
        decrypt: {
          key_id: fake_arn,
          plaintext: FakeKmsClient.key,
          encryption_algorithm: "SYMMETRIC_DEFAULT"
        },
        generate_data_key: {
          ciphertext_blob: FakeKmsClient.encrypted_kms_key_fixture,
          plaintext: FakeKmsClient.key,
          key_id: fake_arn
        }
      }
    end

    def fake_arn
      'arn:aws:kms:us-east-1:000000000000:key/85d5c6c5-2360-4079-8258-b03141a03ff2'
    end
end