Call Rest webservice in Ruby on Rails

rubyonrails-talk
1

Hi every body,

I use rest web service in my rails application for user's authentication (user creation, login, ...) Can someone explain me, how can i call a REST Web service (not developped in Rails, and deployed by Tomcat) in my rails application via POST method.

Thanks in advance for your help

2

I use the Ruby Net::HTTP library to construct requests.

Best regards, Bill

3

I've just used:

data = `curl -data xxx url`

That doesn't seem like the "right" way, but it works.

4

You should also read up on ActiveResource.

5

Define a class like this in your models folder

class MyUserWS < ActiveResource::Base     self.site = "http://localhost/&quot; # point this to the location of your web service     self.format = :json # default format is xml. include this line if you want json     self.element_name = "users" # if your class name (MyUserWS in this case) is different from the name of the webservice you are calling, Mention the real name here     self.user = "myself@elitmus.com" # if your webserive need user authentication mention user name and password     self.password = "mypassword" end

Once you have this... you can instanciate MyUserWS as if it is a model on local database table. You can do all activerecord operations on it as you do on your models

Regards Shireesh

6

Thanks to all for your answer. Bill, can you show me please how you you use the NET::HTTP library to call web service.

Because i have used the NET::HTTP libray like the following, but i alway got 405 error and web service is not called. I have the signup method in my user controller!

def signup       require "net/http"       require "uri"

      user= User.new(params[:firstname], params[:lastname],params[:password],params[:mobilenumber],params[:email])       uri = URI.parse("myWebServiceUrl")       http = Net::HTTP.new(uri.host, uri.port)

      request = Net::HTTP::Post.new(uri.request_uri)       request.set_form_data({ "password" => "MyPassword","firstname"=>"yourFirstname", "lastname"=>"yourLatsname", "email"=>"email@yahoo.com","mobilenumber"=>"1234567890"})       response, data = http.request(request)

      render :text => "#{data}"   end

Thanks for your help

7

Hi,

To send data from an action I do this:

def send_mydata   ...   uri = URI.parse(link)   net_http = Net::HTTP.new(uri.host, uri.port)   net_http.open_timeout = timeout   net_http.read_timeout = timeout   net_http.use_ssl = (uri.scheme == 'https')# enable SSL/TLS   if net_http.use_ssl?     net_http.cert = OpenSSL::X509::Certificate.new(File.read(cert_path))     net_http.key = OpenSSL::PKey::RSA.new(File.read(key_path))     net_http.verify_mode = OpenSSL::SSL::VERIFY_NONE   end

  self.response_body = proc do |response, output|     net_http.start do |http|       http.request_get(uri.request_uri()) do |res|         case res           when Net::HTTPSuccess then             res.read_body do |segment|               response.write(segment)             end           when Net::HTTPRedirection then             response.close() unless response.closed?             return           else             raise "Net::HTTPResponse error: #{res.message.to_s()}"          end       end     end   end end

8

Hi, How can i set parameters in this case?

Thanks

9

Hi,

I never tried this, but it should be something like this:

  required_parameters = ["param1=value1", "param2=value2"]   ...   self.response_body = proc do |response, output|     net_http.start do |http|       http.get(uri.path + '?' + required_parameters.join('&'))         case res ...

Maybe, you need to "escape" the required parameters.

Cheers.

10

Allow me to second the recommendation to read up on ActiveResource - this is exactly what it’s designed for, and in fact if you’re also developing the ReST API, you can use ActiveResource to impose convention (over configuration) in your API - plus you’ll have a nice test rig when you’re done.

Only issue is whether enough people in the Ruby community see AR this way and whether it will continue to be maintained.

m