Migranize

Migranize is a Ruby gem that automatically generates Rails migration files by analyzing changes in your models, similar to Django's migration system.

Features

• Automatically detect changes in your Rails models
• Generate migration files based on model changes
• Simple CLI commands for generating migrations
• Seamless integration with Rails' migration system
• Inspired by Django's migration workflow

Installation

Add this line to your application's Gemfile:

gem 'migranize'

And then execute:

bundle install

Setup

Initialize Migranize in your Rails project:

bundle exec migranize init

This will create a configuration file at config/migranize.rb.

Usage

Define your models

Define your models using the field system provided by Migranize:

# app/models/user.rb
class User < ApplicationRecord
  field :name, :string
  field :email, :string
  field :age, :integer
  field :active, :boolean, default: true
  
  has_many :posts
end

# app/models/post.rb
class Post < ApplicationRecord
  field :title, :string
  field :content, :text
  field :published_at, :datetime
  
  belongs_to :user
end

Generate migrations

After defining or changing your models, generate migrations with:

bundle exec migranize make_migrations

This will analyze your models, detect changes, and create migration files in your db/migrate directory.

Run migrations

Once the migrations are generated, run them using Rails' standard command:

rails db:migrate

Configuration

You can customize Migranize's behavior in the configuration file (config/migranize.rb):

Migranize.configure do |config|
  # Namespaces to ignore when detecting model changes
  config.ignore_namespaces = []
  
  # Tables to ignore when generating migrations
  config.ignore_tables = []
  
  # Directory where migration files are stored
  config.migrations_dir = "db/migrate"
  
  # Directory where model files are stored
  config.models_dir = "app/models"
end

Field Types

Migranize supports all standard ActiveRecord column types:

:string
:text
:integer
:float
:decimal
:datetime
:time
:date
:binary
:boolean
:json
:jsonb (PostgreSQL only)
:uuid (PostgreSQL only)

Field Options

You can specify various options when defining fields:

field :name, :string, null: false
field :price, :decimal, precision: 10, scale: 2
field :status, :string, default: "pending"
field :metadata, :json, null: true

Examples

Basic Model Definition

class Product < ApplicationRecord
  field :name, :string
  field :description, :text
  field :price, :decimal, precision: 10, scale: 2
  field :in_stock, :boolean, default: true
  field :released_at, :datetime
end

Adding or Changing Fields

When you add or change fields in your model:

class Product < ApplicationRecord
  field :name, :string
  field :description, :text
  field :price, :decimal, precision: 10, scale: 2
  field :in_stock, :boolean, default: true
  field :released_at, :datetime
  field :category, :string  # New field
  field :tags, :json  # New field
end

Running migranize make_migrations will generate a migration that adds these new fields to your table.

License

The gem is available as open source under the terms of the MIT License.