How to use Savon in Ruby on Rails Application

In this tips I am going to introduce you to web service API call. I am using http://webservicex.net/

“WebserviceX.NET provides programmable business logic components and standing data that serve as “black boxes” to provide access to functionality and data via web services”.

I am going to use one of its web service  which is “Currency Convertor “ and wsdl schema location is http://www.webservicex.net/CurrencyConvertor.asmx?WSDL  We have a very good gem for SOAP API call in Ruby on Rails which is Savon. I am going to use it and show you how to use it.

First let’s create a new rails application and name it CurrencyConverter (or any other name you like). Then add this “gem ‘savon’ “ to gem file and bundle it.

Create a controller with name public with index and create action and model CurrencyConverter.

Code for controller is below and it is self explanatory.

class PublicsController < ApplicationController

  #purpose: for showing the home page for the application

  def index

  end

 #purpose: for calculating the currency convertion rate

# params : params[:fromCurrency],params[:toCurrency]

# return :  convertion rate

  def create

    # creating a object of the CurrencyConverter model

    currency = CurrencyConverter.new(params[:fromCurrency],params[:toCurrency])

    render :json => currency.result

  end

end

Code for model is below

class CurrencyConverter

  attr_reader :result

  # purpose :  for initializing the object of currency converter

  # params : fromCurrecny(unit),toCurrency(unit)

  # return : none

  def initialize(fromCurrency , toCurrency)

    # creating a client from the wsdl schema

    client = Savon::Client.new("http://webservicex.net/currencyconvertor.asmx?wsdl")

    # calling the api with fromCurrecny and toCurrency unit

    response = client.request :web, :conversion_rate, body: {

                       "FromCurrency" =>     fromCurrency , "ToCurrency" => toCurrency

                      }

    #checking for success of api call

    if response.success?

      data = response.to_array(:conversion_rate_response).first

      if data

        # setting convertion rate to result   

        @result = data[:conversion_rate_result]

      end

    end

  end

end

The index.html.erb view is like

     From Currency Unit

     

          Select Currency

 

British Pound

Indian Rupee

Pakistani Rupee

Singapore Dollar

South African Rand

U.S. Dollar

               

  

 

  To Currency Unit

 

          Select Currency

British Pound

Indian Rupee

Pakistani Rupee

Singapore Dollar

South African Rand

U.S. Dollar

  

  

  

I have used ajax call for submitting this fromCurrency And toCurrency unit.The code for it is

$(document).ready(function(){

    var rate = 0.0;

    var fromCurrency = $("#from_currency");

    var toCurrency= $("#to_currency");

    var fromAmount = $("#from_amount");

    var toAmount = $("#to_amount");

    var  button = $(“# get_conversion_rate”);

 

    var getConversionRate = function(){

        $.post('/publics',{

            fromCurrency : fromCurrency.val(),

            toCurrency : toCurrency.val()

          },function(data) {

            rate = data;

            toAmount.val(fromAmount.val()*rate);

       });

    };

var initialize = function(){

button.click(getConversionRate);

 };

initializer();

 

});