Ruby SDK

Send email with Grape

Use Parcel Wing from Grape APIs with declared params and helper-backed SDK clients.

Install the SDK

The official Ruby SDK is published as parcelwing.

Terminal

gem install parcelwing

Send from an API resource

Declare request params, keep the API key server-side, and translate SDK errors into JSON API responses.

api.rb

require "grape"
require "parcelwing"
 
class API < Grape::API
  format :json
 
  helpers do
    def parcelwing
      @parcelwing ||= ParcelWing::Client.new(api_key: ENV.fetch("PARCELWING_API_KEY"))
    end
  end
 
  resource :emails do
    params do
      requires :email, type: String
      optional :first_name, type: String
    end
    post :welcome do
      emails = parcelwing.emails.send(
        from: ENV.fetch("PARCELWING_FROM_EMAIL"),
        to: params[:email],
        template_alias: "welcome",
        template_params: { first_name: params[:first_name] || "friend" }
      )
 
      { id: emails.first.fetch("id") }
    rescue ParcelWing::Error => error
      error!({ error: error.code, request_id: error.request_id }, error.status || 500)
    end
  end
end

Production notes

Keep PARCELWING_API_KEY in server-side environment variables.
Use saved templates for onboarding, invites, receipts, and account notifications.
Log request_id from ParcelWing::Error for support and debugging.