module Google::Cloud

def self.init_configuration
  configure do |config|
    default_project = Google::Cloud::Config.deferred do
      ENV["GOOGLE_CLOUD_PROJECT"] || ENV["GCLOUD_PROJECT"]
    end
    default_creds = Google::Cloud::Config.deferred do
      Google::Cloud::Config.credentials_from_env \
        "GOOGLE_CLOUD_CREDENTIALS", "GOOGLE_CLOUD_CREDENTIALS_JSON",
        "GOOGLE_CLOUD_KEYFILE", "GOOGLE_CLOUD_KEYFILE_JSON",
        "GCLOUD_KEYFILE", "GCLOUD_KEYFILE_JSON"
    end
    config.add_field! :project_id, default_project,
                      match: String, allow_nil: true
    config.add_alias! :project, :project_id
    config.add_field! :credentials, default_creds, match: Object
    config.add_alias! :keyfile, :credentials
    config.add_field! :on_error, nil, match: Proc
  end
end