Leolay Generators

Version     Travis CI   Quality

A layout and customized scaffold generator for Rails to combine with active admin gem It generates the layout, the style, the internationalization and it helps you to startup active_admin gems


This version has been tested on Rails 4.2 to 5.0.beta2 and Ruby 2.2.3 on Windows OS and Linux Click on Travis badge for more details. For previous version go to the bottom of this read me.


gem install active_leonardo


rails new ActiveLeo -m https://db.tt/gPe6A0l9

or click here to download the template.

You can also get it from the gem root folder


Once you install the gem, the generators will be available to all Rails applications on your system.

To run the generator, go to your rails project directory and type:

rails generate leolay || rails destroy leolay
rails generate leosca || rails destroy leosca

You can run it more times and right like scaffold, it's smart and won't generate tons of identical code (thanks thor)

Warning: Leosca destroy do not remove variables parts inserted into feed like time values.

Step by step

  1. Firstly, create layout and initialize your project:

    rails new ActiveLeo -m YOUR_TEMPLATE_PATH (see above: install paragraph)

    Answer y to all gems you need. After the questions it will start generations. If it is the first generation there will be a conflict on locales/en.yml, type y to overwrite.

    Will be:

    • Created a default layout like active admin
    • Created i18n files
    • Created user management on active admin
    • Customized application.rb to exclude javascript and stylesheet for every resource you will create
  2. You will get an application ready to work, run:

    rake db:migrate
    rake db:seed


    rails s

    and try it on http://localhost:3000

    If you get this message:

    undefined local variable or method `new_user_registration_path'

    be sure user model have :registerable devise's module otherwise add it into user model or you have to remove registerable code from


    You can login as three different profiles as set in db\seeds.rb:

    1. admin@activeleo.com, password: abcd1234 [this profile can do everything]
    2. manager@activeleo.com, password: abcd1234 [can read, create, update and destroy]
    3. user@activeleo.com, password: abcd1234 [can read, create and update]

    There is a fourth profile for guest users who can only see the data. In addition to these you can create all the profiles you need according to cancan rules.

  3. Create your resource:

    rails g leosca product name:string description:text active:boolean items:integer price:decimal

    This will act as a normal scaffold and has more new features:

    1. will be invoked new leosca_controller which is a customized scaffold_controller
    2. attributes will be insert into i18n files for a quick translation
    3. seeds will be created for you to populate new table
    4. invoke active admin generator to add the new resource with a custom configuration to work with cancan
  4. Apply to db as always you do:

    rake db:migrate
    rake db:seed

That's all! The new application is ready to be customized to suit your needs:

  • start to develop user front end
  • take advantage of active admin and its dsl to quickly setup administration section

You could also customize leonardo templates both views and controller. To copy under your project folder run:

rails g leosca:install

Then go to


to edit erb views like you would do with original scaffold. Go to


if you want to customize more.

For more information about usage:

rails g leolay --help
rails g leosca --help



rails generate leolay
rails generate leolay --skip-authentication --skip-authorization


rails generate leosca product name:string
rails generate leosca product name:string --skip-seeds
rails generate leosca product name:string --seeds=60          => if you need more records

if you made a mistake and want to start from scratch just replace generate with destroy to remove all files and inserted code

Of course, these options are in addition to those provided by the original scaffold

Massive resources generation's

Write the resources you want to generate into the file scaffold.txt in the root app. A line for every resource, starting from the beginning with the name as you would with the scaffold. If the line is not a resource but another generator, you can simply starting with the full rails command. Example:

# This is the main resource... i think
activity user:references name:string{100} body:text completed:boolean percentage_progression:integer{1}
#completed: when all tasks are completed
# Any other comments about fields

# This table acts as...
task user:references activity:references name:string{100} body:text completed:boolean percentage_progression:integer{1} deadline_date:date

# I decided to add this because...
rails g migration AddFooToActivity foo:boolean

# I need this because...
rails g migration AddBarToTask bar:boolean

then let active leonardo work for you:

rails generate leosca:massive

and check the report:

create ...
insert ...
append ...
etc ...
Generations started at 18:07:45
18:07:46 - generations ended in 1 second(s)
4 generations executed
9 lines discarded (comments etc.)

of course you can even revert:

rails destroy leosca:massive

This is very useful for a rapid prototyping and if you keep it updated you can use it as information center about the database.

If you try that example remember to add the traslation of the two field foo and bar (added by migrations), otherwise you will get a translation error.

Available layout

Currently the only one available is provided by ActiveAdmin

  • active [default]

How to test this project locally

Download this project and go inside the folder

Install the bundle wherever you want:

bundle install --path=mybundle

Check current tasks typing:

rake -T
rake active:tests:all[inspection,rails_versions]  # Tests all rails versions
rake active:tests:newapp[inspection,rails]        # Creates a test rails ap...
rake active:tests:prepare[rails,path]             # Prepare the environment...

If you want to test everything we planned

rake active:tests:all[inspection]

if you pass the argument inspection you can check the application under the test folder:


where xxx is the current ruby version and the last number the rails version. Remember everytime you run a test that folders will be deleted and recreated.

Every rails version has its own bundle under ActiveLeonardo\mybundle_xx folder.

If you want to specify the rails version type:

rake active:tests:all[inspection,4.2]

or multiple versions

rake active:tests:all[inspection,4.1-4.2]

you may also specify your rails as ENV variables, for example on windows:

set CI_RAILS=4.2
bundle install --path=mybundle_42
rake active:tests:newapp[inspection,4.2]

Do NOT exec rake tests from bundle to avoid its bubble.

Ruby 1.9

Supported until 0.6.x version

Rails 3.2.x

Supported until 0.6.x version

Rails 3.1.x

It should work but has not been tested

Rails 2 and Rails 3.0.x

This Generators does not work with versions earlier 3.1


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Found a bug?

Please open an issue.


  1. Fork it
  2. Create your feature branch (git checkout -b my-feature)
  3. Commit your changes (git commit -am 'I made extensive use of all my creativity')
  4. Push to the branch (git push origin my-feature)
  5. Create new Pull Request


The GNU Lesser General Public License, version 3.0 (LGPL-3.0) See LICENSE file