SequenceId is the gem for Rails 3 that allows for creating URL permalinks that start from 1 and increment in a continuum. As an example for a SaaS based accounting application using SequenceId, you'll have the first three URL's for a new signup like:
http://company1.7vals.com/invoices/1 http://company1.7vals.com/invoices/2 http://company1.7vals.com/invoices/3
http://company1.7vals.com/invoices/11232 http://company1.7vals.com/invoices/11240 #notice a jump of 8 id's due to other companies creating their invoices http://company1.7vals.com/invoices/11242
SequenceId is a fairly straight forward gem and you need to ensure only ONE condition Resource with sequenceid must be a NESTED resource
Back to our original example, if you want invoices to start from 1 for each new company, the Invoice RESOURCE is nested to the Company RESOURCE. The gem will check for the relationhip in the database (Invoice table in this case) and ensure the sequence_num (SequenceId column created in the table) and the parent resource_id are a secondary compound key in the nested resource's table.
At no point is the sequence_num changed once its assigned since it will serve as one of the columns of the compound secondary key. If you ever do rollback the migration, be careful since re-running the migration might result in a different sequence_num if a nested resource is deleted.
SequenceId is compatible with Active Record 3.0.
rails new my_app cd my_app # add to Gemfile gem "sequenceid" bundle install rails generate sequenceid <parent resource> <nested resource> #eg rails generate sequenceid Company Invoice rake db:migrate # edit app/controller/invoices_controller.rb # :id is NO LONGER a unique identifier since its the sequence_num, so you MUST edit the resource find in each of the actions (or create a before filter) @company = Company.find(params[:company_id]) # or Company.find_by_name(request.subdomain) @invoice = @company.invoices.find_by_sequence_num!(params[:id]) rails server #i assuming you have 7vals mapped to localhost in your host file GET http://company1.7vals.com:3000/invoices/1 Get http://company2.7vals.com:3000/invoices/1
Supports Single Table Inheritance. Follow the above given steps in the base class, and all inherited STI classes for the model will share the sequence id generation. ie If base model is Animal, and STI are Dog and Cat, then the sequence numbers will be unique to animal. Meaning given a sequence number, you could identify either an animal uniquely whether it be a dog or a cat.
Please report them on the Github issue tracker for this project.
If you have a bug to report, please include the following information:
- Version information for SequenceId, Rails and Ruby.
- Stack trace and error message.
- Any snippets of relevant model, view or controller code that shows how your are using SequenceId
SequenceId was create by Syed Ali @ 7vals
Special thanks to
for serving as a template on certain best practices.
Copyright (c) 2011, released under the MIT license.