ROR web services: XML and JSON

Ruby on Rails makes web services unfairly easy to build. It gives ROR programmers such an advantage - probably, Rails should be banned.

Here how we make a web service: (based on Simple web service API with Ruby on Rails)

Create a simple application:


rails new eventsservices
cd eventsservices
rails g scaffold event title:string time:datetime
rake db:migrate
rails s

Open http://localhost:3000/events/, click "New Event" and type in some data.

Interesting part is here: by default, ROR knows how to show data in html JSON:

1.   # GET /events/1
2.   # GET /events/1.json
3.   def show
4.     @event = Event.find(params[:id])
6.     respond_to do |format|
7.       format.html # show.html.erb
8.       format.json { render json: @event }
9.     end
10.   end

Adding xml is easy:

1.   # GET /events/1
2.   # GET /events/1.json
3.   # GET /events/1.xml  
4.   def show
5.     @event = Event.find(params[:id])
7.     respond_to do |format|
8.       format.html # show.html.erb
9.       format.json { render json: @event }
10.       format.xml { render xml: @event }      
11.     end
12.   end

Check it out:

A problem here is that this approach does not work with show fuction (ALL Events) in xml part ("Template is missing")

So, let's use a modern  respond_to/respond_with functions:

1.   respond_to :html, :xml, :json
2.   # GET /events
3.   # GET /events.json
4.   # GET /events.xml
5.   def index
6.     respond_with(@events = Event.all)
7.   end
8.  
9.   # GET /events/1
10.   # GET /events/1.json
11.   # GET /events/1.xml  
12.   def show
13.     @event = Event.find(params[:id])
14.     respond_with(@events = Event.all)
15.   end

And here we are. Bingo!

...little bit more on json customization here.