class Google::Cloud::Bigquery::Service::Backoff

def execute
  current_retries = 0
  loop do
    return yield
  rescue Google::Apis::Error => e
    raise e unless retry? e.body, current_retries
    @backoff.call current_retries
    current_retries += 1
  end
end

def initialize retries: nil, reasons: nil, backoff: nil
  @retries = (retries || Backoff.retries).to_i
  @reasons = (reasons || Backoff.reasons).to_a
  @backoff = backoff || Backoff.backoff
end

def retry? result, current_retries
  if current_retries < @retries && retry_error_reason?(result)
    return true
  end
  false
end

def retry_error_reason? err_body
  err_hash = JSON.parse err_body
  json_errors = Array err_hash["error"]["errors"]
  return false if json_errors.empty?
  json_errors.each do |json_error|
    return false unless @reasons.include? json_error["reason"]
  end
  true
rescue StandardError
  false
end