module API
  # Environments RESTfull API endpoints
  class Environments < Grape::API
    before { authenticate! }

    params do
      requires :id, type: String, desc: 'The project ID'
    end

    resource :projects do
      desc 'Get all environments of the project' do
        detail 'This feature was introduced in GitLab 8.11.'
        success Entities::Environment
      end

      params do
        optional :page,     type: Integer, desc: 'Page number of the current request'
        optional :per_page, type: Integer, desc: 'Number of items per page'
      end

      get ':id/environments' do
        authorize! :read_environment, user_project

        present paginate(user_project.environments), with: Entities::Environment
      end

      # ----------------------------------------------------------------

      desc 'Creates a new environment' do
        detail 'This feature was introduced in GitLab 8.11.'
        success Entities::Environment
      end

      params do
        requires :name,           type: String,   desc: 'The name of the environment to be created'
        optional :external_url,   type: String,   desc: 'URL on which this deployment is viewable'
      end

      post ':id/environments' do
        authorize! :create_environment, user_project

        create_params = declared(params, include_parent_namespaces: false).to_h
        environment = user_project.environments.create(create_params)

        if environment.persisted?
          present environment, with: Entities::Environment
        else
          render_validation_error!(environment)
        end
      end

      # ----------------------------------------------------------------

      desc 'Updates an existing environment' do
        detail 'This feature was introduced in GitLab 8.11.'
        success Entities::Environment
      end

      params do
        requires :environment_id, type: Integer,  desc: 'The environment ID'
        optional :name,           type: String,   desc: 'The new environment name'
        optional :external_url,   type: String,   desc: 'The new URL on which this deployment is viewable'
      end

      put ':id/environments/:environment_id' do
        authorize! :update_environment, user_project

        environment = user_project.environments.find(params[:environment_id])

        update_params = declared(params, include_missing: false).extract!(:name, :external_url).to_h
        if environment.update(update_params)
          present environment, with: Entities::Environment
        else
          render_validation_error!(environment)
        end
      end

      # ----------------------------------------------------------------

      desc 'Deletes an existing environment' do
        detail 'This feature was introduced in GitLab 8.11.'
        success Entities::Environment
      end

      params do
        requires :environment_id, type: Integer,  desc: 'The environment ID'
      end

      delete ':id/environments/:environment_id' do
        authorize! :update_environment, user_project

        environment = user_project.environments.find(params[:environment_id])

        present environment.destroy, with: Entities::Environment
      end
    end
  end
end

I propose: ``` ruby module API # Environments RESTfull API endpoints class Environments < Grape::API before { authenticate! } params do requires :id, type: String, desc: 'The project ID' end resource :projects do desc 'Get all environments of the project' do detail 'This feature was introduced in GitLab 8.11.' success Entities::Environment end params do optional :page, type: Integer, desc: 'Page number of the current request' optional :per_page, type: Integer, desc: 'Number of items per page' end get ':id/environments' do authorize! :read_environment, user_project present paginate(user_project.environments), with: Entities::Environment end # ---------------------------------------------------------------- desc 'Creates a new environment' do detail 'This feature was introduced in GitLab 8.11.' success Entities::Environment end params do requires :name, type: String, desc: 'The name of the environment to be created' optional :external_url, type: String, desc: 'URL on which this deployment is viewable' end post ':id/environments' do authorize! :create_environment, user_project create_params = declared(params, include_parent_namespaces: false).to_h environment = user_project.environments.create(create_params) if environment.persisted? present environment, with: Entities::Environment else render_validation_error!(environment) end end # ---------------------------------------------------------------- desc 'Updates an existing environment' do detail 'This feature was introduced in GitLab 8.11.' success Entities::Environment end params do requires :environment_id, type: Integer, desc: 'The environment ID' optional :name, type: String, desc: 'The new environment name' optional :external_url, type: String, desc: 'The new URL on which this deployment is viewable' end put ':id/environments/:environment_id' do authorize! :update_environment, user_project environment = user_project.environments.find(params[:environment_id]) update_params = declared(params, include_missing: false).extract!(:name, :external_url).to_h if environment.update(update_params) present environment, with: Entities::Environment else render_validation_error!(environment) end end # ---------------------------------------------------------------- desc 'Deletes an existing environment' do detail 'This feature was introduced in GitLab 8.11.' success Entities::Environment end params do requires :environment_id, type: Integer, desc: 'The environment ID' end delete ':id/environments/:environment_id' do authorize! :update_environment, user_project environment = user_project.environments.find(params[:environment_id]) present environment.destroy, with: Entities::Environment end end end end ```