Trackerx API

Trackerx package tracking API.

Installation

1. Clone repository.

2. Have PostreSQL, Redis and Ruby 2.7.2 installed.

3. Run:

   bundle install

4. Create a .env file at the root of the project with the specified values in .env.example.

5. Run tests with:

   rspec

6. You can start the API with 2 terminals:

   # terminal 1
   rails s
   # terminal 2
   sidekiq

7. You can access the Swagger docs on /api-docs

Configuration for new trackers

In the event you want to add new trackers, follow these steps:

We will be using as a example UPS.

1. Add a new instance method named ups_tracker in lib/tracking_instance/tracking_instance.rb

   # lib/tracking_instance/tracking_instance.rb
   
   # ...
   def ups_tracker(tracking_number)
     perform_job(tracking_number, UpsTrackerWorker)
   end

2. Create a new worker class UpsTrackerWorker in app/workers

   # app/workers/ups_tracker_worker.rb
   # frozen_string_literal: true
   
   class UpsTrackerWorker
     include Sidekiq::Worker
     include Sidekiq::Throttled::Worker
   
     sidekiq_options queue: :normal
     sidekiq_throttle_as :delivery_api
   
     def perform(tracking_number)
       Tracker::UpsTracker.call(tracking_number: tracking_number)
     end
   end

3. Create a new tracker class Tracker::UpsTracker in app/services/tracker

   # app/services/tracker/ups_tracker.rb
   # frozen_string_literal: true
   
   module Tracker
     class UpsTracker < ApplicationTracker
       include ::Constants::UpsTracking
   
       def call
         with_retry(number_of_retries, retries_interval, EXCEPTIONS) do
           Timeout.timeout(timeout) do
             tracking_info = track_package
             status = STATUS_CODES[tracking_info.status_code.to_sym].presence || 'EXCEPTION'
   
             Sidekiq.logger.info(status) unless Rails.env.test? # just for challenge visualization purpose
             status
           end
         end
       rescue => e
         Sidekiq.logger.error(e.message) unless Rails.env.test?
         false
       end
   
       private
   
       def track_package
         # this method will return the UPS tracking_info for the specified tracking_number
       end
   
       def ups
         return @ups if defined? @ups
   
         @ups = nil # UPS service initialization
       end
     end
   end

4. Create a file of the UPS constants needed to return the correct statuses and exceptions to raise named Constants::UpsTracking in lib/constants

   # lib/constants/ups_tracking.rb
   # frozen_string_literal: true
   
   module Constants
     module UpsTracking
       EXCEPTIONS = [
         # list of exceptions for this tracker to be catched and raised when they happen
       ].freeze
   
       STATUS_CODES = {
         # list of status codes for this tracker and their correspondant application status
         # ...
         OC: 'CREATED', # Order Created
         IT: 'ON_TRANSIT', # In Transit
         DL: 'DELIVERED', # Delivered
         SE: 'EXCEPTION' # Shipment Exception
         # ...
       }.freeze
     end
   end