lib/facebook/messenger/configuration/app_secret_proof_calculator.rb
module Facebook
module Messenger
class Configuration
# We provide a service to calculate an app_secret_proof
class AppSecretProofCalculator
def self.call(app_secret, access_token)
OpenSSL::HMAC.hexdigest(
OpenSSL::Digest.new('SHA256'.freeze),
app_secret,
access_token
)
end
end
end
end
end