Pushpalanka's Blog

With this post I am hoping to share the procedure to set up Apache Hadoop in single node. Hadoop is used in dealing with Big Data sets where deployment is happening on low-cost commodity hardware. It is a map-reduce framework which map segments of a job among the nodes in a cluster for execution. Though we will not see the exact power of Hadoop running it on single node, it is the first step towards the multi-node cluster. Single node set up is useful in getting familiar with the operations and debugging applications for accuracy, but the performance may be far low than what is achievable. I am sharing the steps to be followed on a Linux system, as it is supported as both a development and a  production platform for Hadoop. Win32 is supported only as a development platform and equivalent commands for the given Linux commands need to be followed. This  Hadoop document  includes the details for setting up Hadoop, in brief. I am here sharing a detailed guidance f...

I am here sharing a nice tool I recently found to draw the diagrams for my final year project at university. When the project is concerned, managing it is challenging with,  code base of the project is pretty large a team is working on the project we need to maintain the quality and performance of the project  proper documentation is also evaluated So we were searching for an easy to use and nice looking tool to achieve the purposes without making it annoying that, we can focus more on the logic and optimization than decorating a diagram. :) That is were I found this plugin for eclipse  called Architexa client, which is free for use. Following is a sequence diagram I generated using the plugin, which didn't take more than 30s to draw than dragging the relevant classes and setting the relevant calls. Following is a class diagram generated, that you can clearly observe the clear and smart look of the diagrams. Pros: From several t...

Through this I am sharing the most simple scenario to follow in using Java keytool for the requirements of Apache Wookie projects digital signature implementation. Anyway if you are looking to know how to generate a key pair or import a certificate to a Keystore using keytool, still this may be helpful. Refer this segment of Java SE documentation to know in-depth details. You needs a configuration of Java in your computer to use keytool and that is enough :). Generating Key Pairs Use following command in command prompt to generate a keypair with a self-signed certificate keytool -genkey -alias wookie -keyalg RSA -keystore wookieKeystore.jks -keysize 4096 After  -alias give the alias to be used for keys           -keylag give the algorithm to be used in key generation          -keystore give the name of the keystore with type .jks (You can give a path here to store the keystore in a desired place)   ...

I am here sharing my GSoC 2012 project details which I enjoyed a lot while learning. This includes a brief introduction on the project with it's design, implementation and guidance on using. The implementation has been done using Apache Santuario 1.5.2 release to generate digital signatures. The project is mentored by Scott Wilson who was so helpful and supported by the community. This is Scott Wilson's post on the project. What is Apache Wookie? Apache Wookie is a Java server application that allows widget uploading and deployment as useful for variety of applications. This may include gadgets to quizzes and games. Wookie has been based on W3C widget specification while providing flexibility on Google Wave gadgets etc. At the moment of writing, it is in the Apache incubator getting ready to graduate as an Apache Project.  Objective of the project The objective this project is to implement the ' W3C XML Digital Signatures for Widgets ' specification i...

This is the presentation we at team 'Kanthaka', did on the major progress evaluation after a thorough literature review on the technologies to be used in developing the big data CDR analyzer. This will be beneficial for anyone who is looking for technologies to deal with big volumes of data with near real time execution speed requirements.   Kanthaka - High Volume CDR Analyzer View more presentations from Pushpalanka Jayawardhana

The 'sstableloader' introduced from Apache Cassandra 0.8.1 onwards, provides a powerful way to load huge volumes of data into a Cassandra cluster. If you are moving from a cloud cluster to a dedicated cluster or vice-versa or  from a different database to Cassandra you will be interested in this tool. As shown below in whatever case if you can generate the 'sstable' from the data to be loaded into Cassandra, you can load it in bulk to the cluster using 'sstableloader'. I have tried it in version 1.1.2 here. With this post I ll share my experience where I created sstables from a .csv file and loaded to a Cassandra instance running on same machine, which acts as the cluster here. sstable generation Bulk loading Cassandra using sstableloader Using JMX 'sstable' generation To generate 'SSTableSimpleUnsortedWriter' the 'cassandra.yaml' file should be present in the class path. In Intellij Idea you can d...

This post gathers the steps I followed in setting up an Apache Cassandra cluster in multi-node. I have referred Cassandra wiki and Datastax documentation in setting up my cluster. The following procedure is expressed in details, sharing my experience in setting up the cluster. Setting up first node Adding other nodes Monitoring the cluster - nodetool , jConsole , Cassandra GUI I used Cassandra 1.1.0 and Cassandra GUI - cassandra-gui-0.8.0-beta1 version(As older release had problems in showing data) in Ubuntu OS. Setting up first node Open cassandra.yaml which is in 'apache-cassandra-1.1.0/conf'. Change listen_address: localhost -->  listen_address: <node IP address>          rpc_address: localhost -->  rpc_address: <node IP address> - seeds: "127.0.0.1" --> - seeds: "node IP address" The listen address defines where the other nodes in the cluster should connect. So in a multi-node cluster it should to...

Here I am sharing the steps I followed in configuring Intellij IDEA to develop Apache Wookie. As guidelines are only given in the site to start with Eclipse IDE , before starting coding I needed to configure Intellij IDEA to be aligned with the practices and conventions of Wookie, before starting coding for GSoC2012. For the project we have to use SVN as version control system and Intellij by default facilitate it. We need to do the following set ups in addition. Dependency management Code style and template Debugging Let’s look at how to deal with these. Dependency management with Apache Ivy Wookie use Ivy as the dependency manager. To easily compile the Wookie project inside Intellij, we need to have the plugging IvyIDEA installed. In order to do so, go to File>Settings>IDE Settings and select IvyIDEA from available pluggings as follows and install. Now once you open Wookie in Intellij, it will auto detect the ivy.xml file a...

Today I got the news of the proposal I submitted to GSoC2012, is accepted. I consider it a great achievement and so excited to make the project a success. With the nature of the program it is no wonder anyone get excited about it. Firstly having the chance to work for a recognized company(In my case Apache) and the global reputation a gsocer can have is so motivational. Also getting started to work with a strange team, getting to know them, work remotely, add good experience to life and high professional value as I guess. It's amazing to work with the community. Also it is a great chance to broaden the horizons in technical skills while having guidance from an expert in the area, having hands on it. Also I'm glad to share about my project, which is to implement 'W3C XML Digital Signatures for Widgets Specification in Apache Wookie . Computer Security has become the favorite field of me followed by Big data after my internship at WSO2 Lanka(pvt) Ltd, with experience I had...

Before Implementing SAML This is how a XACML request will looks like when it is arriving at PDP(Policy Decision Point) to be evaluated. Basically it states who is(Subject) wanting to access which resource and what action it wants to perform on the resource. PDP trusts that request made is not altered while being sent and received, evaluates the request against existing enabled policies and reply with the decision which will be as follows. Again there is no guarantee for the party who is using this response that this decision is not altered since sent from PDP until been received. In order achieve the security of XACML requests and responses in server to server communication SAML profile for XACML is defined by OASIS.This take the system security to a higher level by allowing the usage of fine-grained authorization provided by XACML, to be signed. After Implementing SAML Following is how the previous XACML request looks like after wrapped into a XACMLAuthzDe...