class FollowRemoteAccountService include ApplicationHelper def call(uri) username, domain = uri.split('@') account = Account.where(username: username, domain: domain).first return account unless account.nil? account = Account.new(username: username, domain: domain) data = Goldfinger.finger("acct:#{uri}") account.remote_url = data.link('http://schemas.google.com/g/2010#updates-from').href account.salmon_url = data.link('salmon').href account.public_key = magic_key_to_pem(data.link('magic-public-key').href) account.private_key = nil account.secret = SecureRandom.hex account.verify_token = SecureRandom.hex feed = get_feed(account.remote_url) hubs = feed.xpath('//xmlns:link[@rel="hub"]') return false if hubs.empty? || hubs.first.attribute('href').nil? || feed.at_xpath('/xmlns:author/xmlns:uri').nil? account.uri = feed.at_xpath('/xmlns:author/xmlns:uri').content account.hub_url = hubs.first.attribute('href').value account.save! subscription = account.subscription(subscription_url(account)) subscription.subscribe rescue Goldfinger::Error, HTTP::Error => e false end private def get_feed(url) response = http_client.get(Addressable::URI.parse(url)) Nokogiri::XML(response) end def magic_key_to_pem(magic_key) _, modulus, exponent = magic_key.split('.') modulus, exponent = [modulus, exponent].map { |n| Base64.urlsafe_decode64(n).bytes.inject(0) { |num, byte| (num << 8) | byte } } key = OpenSSL::PKey::RSA.new key.n = modulus key.e = exponent key.to_pem end def http_client HTTP end end