Grape setup with logging & documentation

api.rb

module MyApp
  module V1
    class API < Grape::API
      version 'v1', using: :path
      format :json

      before do
        header['Access-Control-Allow-Origin'] = '*'
        header['Access-Control-Request-Method'] = '*'

        @log_start_t = Time.now
        fil = ActionDispatch::Http::ParameterFilter.new Rails.application.config.filter_parameters
        Rails.logger.tagged('API') do |logger|
          logger.info "Parameters: #{fil.filter params.to_hash.except('route_info')}"
        end
      end

      after do
        @log_end_t = Time.now
        total_runtime = ((@log_end_t -  @log_start_t) * 1000).round(1)
        db_runtime = (ActiveRecord::RuntimeRegistry.sql_runtime || 0).round(1)
        Rails.logger.tagged('API') do |logger|
          logger.info "Completed in #{total_runtime}ms (ActiveRecord: #{db_runtime}ms)"
        end
      end

      rescue_from ActiveRecord::RecordInvalid do |e|
        error_response message: e.record.errors.to_a.uniq.join(', '), status: 400
      end

      rescue_from ActiveRecord::RecordNotFound do |_|
        error_response message: 'Record not found!', status: 404
      end

      rescue_from Grape::Exceptions::ValidationErrors do |e|
        error_response message: e.message, status: 400
      end

      rescue_from :all do |e|
        Rails.logger.tagged('API') do |logger|
          logger.info "error: #{e.message}"
        end

        message = Rails.env.production? ? 'server error' : e.message
        error_response message: message, status: 500
      end

      add_swagger_documentation api_version: 'v1', mount_path: '/api-docs', hide_format: true
    end
  end
end