Fast Versioning

A PaperTrail extension for seamless fast key/value versioning of individual object attributes, which can be queried.

Why?

PaperTrail stores version changes in one serialized column, which is great for keeping backups, undoing, etc. For querying and searching this is a real pain to use, and sometimes you need to track single column changes that you can query, use for statistics, quickly check last changes. You can also use Fast Versioning to track more complex object state changes!

How?

We hook up to PaperTrail version creation, check if an object's tracked attribute changed and store any changes individually.

Installation

1. Add to the Gemfile and bundle

gem 'fast_versioning'

2. Install migrations

rake fast_versioning:install:migrations

Prerequisites

• PaperTrail needs to be added to your model
• Storing changes needs to be enabled for PaperTrail
• Attributes tracked with FastVersioning need to also be present in PaperTrail ie.

has_paper_trail only: :status
has_fast_versions :status

Configuration

1. Include the concern in your model

include FastVersioning::FastVersioned
has_paper_trail

    ...
# define what you want to track
has_fast_versions(
  :plan_id,
  :plan_type,
  status: {
    billed_statements: Proc.new { |account| account.utility_statements.count },
    static_value: 'text'
  }
)

# plan_id - is a attribute
# plan_type - is a custom method
# status - defines an additional serialized meta apart from storing property change

Usage

Creating and recreating fast versions

FastVersioning versions are created based on the PaperTrail::Version instance. When available, the changeset is used, otherwise, FastVersioning will attempt to reify the object comparing the changes for the tracked columns.

At any point you can retroactively recreate FastVersioning versions (especially, initially, when adding fast versions to existing PaperTrail configuration, or when adding/changing FastVersioning options for a model), to do so you need to call the recreate_fast_versions! on the PaperTrail::Version instance. It will destroy all previous fast versions if they exist and recreate them.

Example usage:

    # recreate fast versions for a single model instance
    your_model.versions.find_each(&:recreate_fast_versions!)

    # recreate fast versions for all model instances
    YourModel.find_each { |your_model| your_model.versions.find_each(&:recreate_fast_versions!) }

Querying

    your_model.fast_versions # get all fast versions
    your_model.fast_versions_for(:plan_type) # get fast versions for given property - chain
    your_model.fast_versions.last.version # get parent paper_trail version object
    your_model.fast_versions.last.item # get changed item
    your_model.fast_versions.last.name # property name
    your_model.fast_versions.last.value # get value
    your_model.fast_versions.last.prev_value # get value before the change

    # query
    your_model.fast_versions_for(:status).where(value: 'active').where(prev_value: 'incomplete')

    # alternatively:
    FastVersioning::FastVersion.find_by(
      item_type: 'ItemType',
      name: 'name',
      value: 'value'
      prev_value: 'prev_value'
    )

Timeline helper

FastVersioning::Timeline is a simple helper you can use to generate a timeline hash for a tracked property

example usage:

FastVersioning::Timeline.new(
  fast_versions: model.fast_versions,
  name: "status"
).to_h

# {
#   Thu, 01 Apr 2021 14:08:48 EDT -04:00..Mon, 05 Apr 2021 21:53:48 EDT -04:00 => 'active',
#   Mon, 05 Apr 2021 21:53:48 EDT -04:00..Mon, 05 Apr 2021 22:02:44 EDT -04:00 => 'inactive',
#   Mon, 05 Apr 2021 22:02:44 EDT -04:00..Infinity => 'active'
# }

Testing

bundle exec appraisal install
bundle exec appraisal rspec

An Arcadia Project