Link Crossing borders: REST on Rails

Create: HTTP put
Read: HTTP get 
Update: HTTP post
Delete: HTTP delete

Listing 6. Rendering HTML for a JavaScript client

def list
   # wants is determined by the http Accept header in the request
   @people = Person.find_all
   respond_to do |wants|
      wants.html
      wants.js
      wants.xml { render :xml => @people.to_xml }
   end    
end

Listing 8. Invoking the service from Ruby 
require 'net/http'

Net::HTTP.start('localhost', 3000) do |http|
  response = http.get('/people/list', 'Accept' => 'text/xml')

  #Do something with the response.

  puts "Code: #{response.code}" 
  puts "Message: #{response.message}"
  puts "Body:\n #{response.body}"
end

Listing 9. Invoking the service with Java code

package com.rapidred.ws;

import java.net.*;
import java.io.*;

public class SimpleGet {

    void get() {

        try {
            URL url = new URL("http://localhost:3000/people/list");
            URLConnection urlConnection = url.openConnection();
            urlConnection.setRequestProperty("accept", "text/xml");
            BufferedReader in = 
              new BufferedReader(new InputStreamReader(urlConnection.getInputStream()));
            String str;

            while ((str = in.readLine()) != null) {
                System.out.println(str);
            }

            in.close();
        }
        catch (Exception e) {
            System.out.println(e);
        }
    }



Listing 10. Calling HTTP post with Java code
void post() {
try {
    String xmlText  = " " +
            "Maggie" +
            "Maggie" +
            "maggie@tate.com" +
        "";

    URL url = new URL("http://localhost:3000/people/create");
    HttpURLConnection conn = (HttpURLConnection)url.openConnection();
    conn.setDoOutput(true);
    conn.setRequestMethod("POST");
    conn.setRequestProperty("Content-Type", "text/xml");
    OutputStreamWriter wr = new 
OutputStreamWriter(conn.getOutputStream());
    wr.write(xmlText);
    wr.flush();

    BufferedReader rd = new BufferedReader(new 
InputStreamReader(conn.getInputStream()));
    String line;
    while ((line = rd.readLine()) != null) {
        System.out.println(line);
    }
    wr.close();
    rd.close();
    } catch (Exception e) {
        System.out.println("Error" + e);
    }
}