Writing a Jaggery Client for secured REST Resource

By: අසදි on 11:45 PM

Every day, the more I learn new stuff,the more I feel exited !!!

Last week I had a delicious bite from {Jaggery.js} and let me share a bit with you all. :)

First we need to setup a {Jaggery.js} server to host the client application we are about to write.

Setting up Jaggery

• Download {Jaggery.js} server from {Jaggery.js} site. 
• Extract jaggery-0.9.0-SNAPSHOT.zip to a directory you prefer. lets call it JAGGERY_HOME
• Navigate to JAGGERY_HOME/bin directory which contains all the Jaggery execution scripts.
• Run sh JAGGERY_HOME/bin/server.sh   ( JAGGERY_HOME/bin/server.bat in windows) command to start the server.

Writing the Jaggery Client

• Goto JAGGERY_HOME/apps directory. 
• Create directory JaggeryClient inside JAGGERY_HOME/apps.
• Create secureClient.jag and Base64Encode.jag files inside JAGGERY_HOME/apps/JaggeryClient directory.

• secureClient.jag file content is as follows.                                                   

• 
  

  1. </%function secure_call(request){                           
  2. var Base64Encode = require("Base64Encode.jag");  
  3. 
     
  4. var username = request.username;                 
  5. var password = request.password;                 
  6. var url = request.url;                           
  7. var data = request.data;                                                                  
  8. var code = "Basic " + username + ":" + password;;
  9. var auth = Base64Encode.base64_encode(code);     
  10. var header = {"Authorization":auth};             
  11. var repleyJson = get(url, data ,header,"json");  
  12.                                                  
  13. response.content  = repleyJson;                  
  14. }                                                        
  15. %> 

• Above request filed is in JSON format as follows.

{ username:"username",password:"password", url:"url of the resource", data:"" }

• Jaggery GET method is used to access the rest resource and Basic Authentication username and password are sent, encoded in the header.

• Base64Encode file content is as follows. [source: http://phpjs.org/functions/base64_encode/]     

• 1. function base64_encode(data) {                           
  2.  var b64 = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=';
  3.   var o1, o2, o3, h1, h2, h3, h4, bits, i = 0,
  4.     ac = 0,
  5.     enc = '',
  6.     tmp_arr = [];
  7. 
     
  8.   if (!data) {
  9.     return data;
  10.   }
  11. 
      
  12.   do { // pack three octets into four hexets
  13.     o1 = data.charCodeAt(i++);
  14.     o2 = data.charCodeAt(i++);
  15.     o3 = data.charCodeAt(i++);
  16. 
      
  17.     bits = o1 << 16 | o2 << 8 | o3;
  18. 
      
  19.     h1 = bits >> 18 & 0x3f;
  20.     h2 = bits >> 12 & 0x3f;
  21.     h3 = bits >> 6 & 0x3f;
  22.     h4 = bits & 0x3f;
  23. 
      
  24.     // use hexets to index into b64, and append result to encoded string
  25.     tmp_arr[ac++] = b64.charAt(h1) + b64.charAt(h2) + b64.charAt(h3) + b64.charAt(h4);
  26.   } while (i < data.length);
  27.  enc = tmp_arr.join('');
  28.  var r = data.length % 3;
  29.  return (r ? enc.slice(0, r - 3) : enc) + '==='.slice(r || 3);
  30. }
  31. %>

• Now we are done with the Jaggery Client.

Accessing secured resource via the Client

• Next we try it with a secured REST Resource as shown in following secureCall.jag.

• 1. <%                                                       
  2. var include = require("secureClient.jag");
  3. include.secure_call({ username:"replace_with_valid_username",password:"replace_with_valid_password", url:"replace_with_valid_url_to secured source", data:"" });
  4. %>

• place above secureCall.jag file in JAGGERY_HOME/apps/JaggeryClient folder and goto http://localhost:9763/JaggerySecureClient/secureCall.jag to see whether it works. 

Hope you enjoyed the taste. 

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