Building a new Rails app with the railsbuilder gem
require 'railsbuilder'
rb = RailsBuilder.new
rb.build
rb.save
The above code will create a new Rails app called site1 and then it will save file site1.cfg containing the following:
# # RailsBuilder configuration file # app: site1 # resources: posts
Creating a basic app with Railsbuilder
In this guide we will create a blog. Create the config file for the blog as show below:
# # railsbuilder configuration file # app: blog
Then run railsbuilder e.g.
require 'railsbuilder'
rb = RailsBuilder.new '~/rails/blog.cfg'
rb.build
It will ask you if want to create a new app, press enter or type y.
Type rails server and observe the web page displayed at http://localhost:3000.
Creating the controller
Add a controller entry called 'welcome' with a method called 'index' to the config file as show below:
#
# railsbuilder configuration file
#
app: blog
welcome
controller + views
index
The run railsbuilder again, it should ask you if you want to generate a new controller. Press y or press enter.
Edit the file app/views/welcome/index.html.erb and replace the H1 tag contents with "Hello, Rails". Then delete the paragraph block below it.
Setting the application home page
Add a root entry called 'welcome#index' to the config file as shown below:
#
# railsbuilder configuration file
#
app: blog
root: welcome#index
welcome
controller + views
index
Save the file and then run railsbuilder again. Observe it displayed the message :: updating config/routes.rb.
Observe localhost:3000 now displays the content from welcome/index.
Adding CRUD to the app
Following on from creating the basic app with a welcome page we are now ready to continue.
Defining resources
Within the config file add the resources statement as show below:
#
# railsbuilder configuration file
#
app: blog
root: welcome#index
resources: posts
welcome
controller + views
index
Creating a Posts controller
Add the posts statement to the config file before the welcome line. Then after posts on the next line, indent by 2 spaces and add the model statement. Then on the next line indented by 2 spaces add the controller + views statement.
Adding an action to the controller
Looking at the config file, within the context of controllers + views on the next line, indented by 4 spaces add the new statement. This instructs railsbuilder to create a method called new in the posts_controller.rb file.
The config file should now look similar to the following:
#
# railsbuilder configuration file
#
app: blog
root: welcome#index
resources: posts
posts
model
controller + views
new
welcome
controller + views
index
Run railsbuilder again, this time try defining an alias command and running it from the command line e.g.
alias build="ruby -r railsbuilder -e \"RailsBuilder.new('~/rails/blog.cfg').build\""
type: build
Note: It would be convenient to store this alias in your bash aliases file.
Now that the new view has been created we could add a form with a submit button, however leave that until later.
Adding an action for submitting a post
When the submit button is pressed its request should be processed by the create method.
Looking at the config file, within the controllers + views section, after new, add a new line, indented by 4 spaces, add the statement create.
Here's how your config file should look:
#
# railsbuilder configuration file
#
app: blog
root: welcome#index
resources: posts
posts
model
controller + views
new
create
welcome
controller + views
index
If you run railsbuilder now, it will create the create method within posts_controller.rb file.
Creating the model
To declare the record fields we will need, add a new line indented by 4 spaces after the model statement, and add the statement Post. Then on a new line indented by 6 spaces add the couple of field definitions as show below:
#
# railsbuilder configuration file
#
app: blog
root: welcome#index
resources: posts
posts
model
Post
title: string
text: text
controller + views
new
create
welcome
controller + views
index
Run railsbuilder and accept the confirmation to generate the model, and migrate the database.
Note: This gem is currently under development.
Resources
rails railsbuilder config gem builder