ABRefactoring

A rough and ready debugging tool to help refactoring / moving logic from one application to another.

Installation

None required, this is a simple repository ready to be used.

Usage

Pasting log data into the project

• paste the log content of your legacy application in logs/a
• paste the log content of your new application in logs/b

Turning server logs into fixtures

Output resources created in database calls, for application a, as YAML.

bundle exec ruby log_parser.rb a

---
insert_products:
  provider_id: '173'
  quantity: '7'
  reference: HJIK4
---
update_providers:
  provider_id: '15935967'
  status: live

Output resources created in database calls, for application a, as Hashes.

bundle exec ruby log_parser.rb a hashes

{"provider_id"=>"173", "quantity"=>"7", "reference"=>"HJIK4"}
{"provider_id"=>"15935967", "status"=>"live"}

Create fixture files

• create a yaml file per resource created in the database
• add those the yaml files under the relevant namespace, e.g fixtures/a for resources created by application a

Edit the spec file

• add as many context as resouces created

Run rspec

• make use of rpsec and its context mechanism to easily isolate potential discrepancies between one resouce created by application a VS application b.

bundle exec rspec spec/resources_spec.rb -e 'the name of my context describing a resource'
# e.g
bundle exec rspec spec/resources_spec.rb -e 'products'

Example provided

Running the spec/resources_spec.rb you will be presented with the following failure.

  1) resources product generate the same attributes
     Failure/Error: expect(application_b_object).to eq application_a_object

       expected: {"provider_id"=>"173", "quantity"=>"7", "reference"=>"HJIK4"}
            got: {"provider_id"=>"173", "quantity"=>"0"}

This illustrates that application b is not currently matching all actions performed by application a.

• quantity has not been set correctly on product
• the reference field has not been processed at all while using application b

Contributing

Bug reports are welcome on GitHub at https://github.com/joe-at-github/a_b_refactoring.