DDevelopment & Design

Hadoop for Enterprises

Hadoop’s usage as a big data processing framework gains a lot of attention lately. Now, not only big players see, that they can embrace the data their sites or products are generating and develop their businesses on it. For that to happen two things are needed: the data itself and means of processing really big amounts of it.

Gathering data is relatively easy. These are not necessarily structured data, you don’t need to plan their usage at first. Just start collecting them and than you may experiment with their potential usage. If they’ll come out as useless rubbish – deleting them won’t be hard But imagine the values it may contribute to your business:

  • faster services – working on optimized data
  • more clients – because of more relevant search results
  • happy clients – your service can “read their minds”
  • etc.

There are many companies that utilize Hadoop ecosystem for their own needs. You can read about some of them here: http://wiki.apache.org/hadoop/PoweredBy But since that page lacks insight into specific applications of Hadoop I’ve tried to delve into

details of how Hadoop helped tame some companies’ big data sets.

Facebook

Being a social network provider, a widely used one, they require no introduction. However if you’ve lived under a rock for last couple years just visit their website http://facebook.com

Their main usage is data warehousing. Since they require to be able to access the data fast and reliably they had a need for real-time querying of their huge, and always growing data set. Their switch from MySQL databases was required due to the increasing workloads they experienced with standard databases. What they got “out of the box” with Hadoop was all the benefits of distributed file system (HDFS features). They expanded the ideas behind that even further and implemented truly Highly Available file system without Single Point of Failure.

Facebook has 3 interesting usage scenarios in which Hadoop plays a major role:

  • Titan – is Facebook’s messaging system. It processes messages exchanged between users. Ensures that it happens fast and without glitches. Here Hadoop is used mainly as a huge, unlimited storage.
  • Puma – Facebook Insights – a tool providing page statistics for advanced Facebook users. Based on streams of data (clicks, likes, shares, comments and impressions) it graphs those data and makes it available near instantly.
  • ODS – Operational Data Store – which stores Facebook’s internal metrics – collections of OS and cluster health metrics. And it facilitates multiple accounting solutions.

Twitter

This popular micro-blogging platform, where you can register your account and follow friends and celebrities for their micro-messages does some pretty interesting things with their Hadoop cluster.

One of their motivations is to speed up their web-page’s functionality. That is why the compute users’ friendships in Twitter’s social graph with Hadoop. Using connections between users they calculate their relationship to each other and estimate groups of users.

Since this service’s users generate lots of content, the company conducts researches based on natural language processing. They probe what could be told about a user from his tweets. They use tweets’ contents for advertisement purpose, trends analysis and many more.

From tweets and user’s behaviours they characterise usage scenarios. Also, they gather usage statistics, like number of searches daily, number of tweets. Based on this seemingly irrelevant data they run comparisons of different types of users. Twitter analyzes data to determine whether mobile users, users who use third party clients or power users use Twitter differently from average users. Of course theses seem like really specific applications but nevertheless they are very original and base on the data that Twitter has been gathering for some time now.

EBay

Being the biggest auctioning site on the Internet, EBay uses Hadoop processing for increasing search relevance based on click-stream data, user data. This seems pretty obvious, considering their area of operation.

However the also have one other interesting thing – they try hard to automatically fill auctioned objects’ metadata, based on the descriptions and other data provided by users. They employ data mining approach for this tasks and judging from their constant growth it seems to work

LinkedIn

Social network for professionals, thou a lot smaller than Facebook. Based on click-streams they discover relations between users. All the data concerning latest visits on your profile or people you may know from other places – this comes from Hadoop based analysis of those clicks people make all the time on their sites.

Also a very neat feature, called InMaps (http://inmaps.linkedinlabs.com/) analyse declared schools and companies and generates data for graph with clustered friends of yours.

Last.fm

This on-line radio site, praised by many for its invaluable recommendations’ system seems like a rather small and simple service. But behind the facade of simple web page there are lots of data being processed, so that their services could match a certain level of perfection.

Such large volume of their data comes from scrobbles. Each users of their service listening to a song generates a note about this fact – called scrobble. Based on that and user profiles they calculate global band popularity charts, maps of bands’ popularity and many more usage statistics and timeline charts.

Conclusion

They just try to detect and trace new patterns in seemingly chaotic data sets. Perhaps you could also do the same? Analyze your data and expand your business value?

Comments

wedding cake decorations

We stumbled over here from a different web address and thought I might check things out.

I like what I see so i am just following you.

Look forward to checking out your web page yet again.

rubber floor mats

I like what you guys are up too. This type of clever work and reporting!

Keep up the awesome works guys I’ve added you guys to my own blogroll.

Svayambhut Ghosh

Greetings from Florida! I’m bored at work so I decided to browse your site on my iphone during lunch break. I enjoy the info you present here and can’t wait to take a look

when I get home. I’m surprised at how quick your blog loaded on my cell phone .. I’m not even using WIFI, just 3G .

. Anyways, very good site!

north face jackets

Comfortableness north face jackets

is crucial when they get it that will north face outlet get the best school bags pertaining to going camping north face sale. Your easiest guarantee in the case of even larger delivers has become One with an inner metal framework, one that can wind cheap north face up being aligned to help you appropriately fit your north face women body. They should be now have http://www.salethenorthfacejackets.com secure which were wholly flexible, because essentially in the form of midsection belt to get more aid.

plants sale

I never imagined how much stuff there was out there

on this! Thanks for making it easy to get the picture

gWgVcetqzVZukd

What Programming Languages Do Jobs Require? | Regular Geek regulargeek.com/2009/07/21/what-programming-languages-do-jobs-require view page cahecd As a software engineer, you need to keep your skills sharp and current. This is a general requirement of the job. In addition to this, in the current economy you do not want to be without a job. Obviously, this means learning more about what your current company uses for all of its development. What if you do not have a job or you are looking to leave? What technologies or programming languages should you be looking into? From the page

computer pc repair

Howdy are using WordPress for your site platform? I’m new to the blog world but I’m trying to

get started and create my own. Do you need any coding expertise to make your own

blog? Any help would be greatly appreciated!

— Previous article

GWT Developer's Plugin for Firefox 13

Next article —

Już w najbliższą sobotę Confitura 2012

You May Also Like
DDevelopment & Design

How to automate tests with Groovy 2.0, Spock and Gradle

This is the launch of the 1st blog in my life, so cheers and have a nice reading!

y u no test?

Couple of years ago I wasn't a big fan of unit testing. It was obvious to me that well prepared unit tests are crucial though. I didn't known why exactly crucial yet then. I just felt they are important. My disliking to write automation tests was mostly related to the effort necessary to prepare them. Also a spaghetti code was easily spotted in test sources.

Some goodies at hand

Now I know! Test are crucial to get a better design and a confidence. Confidence to improve without a hesitation. Moreover, now I have the tool to make test automation easy as Sunday morning... I'm talking about the Spock Framework. If you got here probably already know what the Spock is, so I won't introduce it. Enough to say that Spock is an awesome unit testing tool which, thanks to Groovy AST Transformation, simplifies creation of tests greatly.

An obstacle

The point is, since a new major version of Groovy has been released (2.0), there is no matching version of Spock available yet.

What now?

Well, in a matter of fact there is such a version. It's still under development though. It can be obtained from this Maven repository. We can of course use the Maven to build a project and run tests. But why not to go even more "groovy" way? XML is not for humans, is it? Lets use Gradle.

The build file

Update: at the end of the post is updated version of the build file.
apply plugin: 'groovy'

apply plugin: 'idea'


def langLevel = 1.7


sourceCompatibility = langLevel

targetCompatibility = langLevel


group = 'com.tamashumi.example.testwithspock'

version = '0.1'


repositories {

    mavenLocal()

    mavenCentral()

    maven { url 'http://oss.sonatype.org/content/repositories/snapshots/' }

}


dependencies {

    groovy 'org.codehaus.groovy:groovy-all:2.0.1'

    testCompile 'org.spockframework:spock-core:0.7-groovy-2.0-SNAPSHOT'

}


idea {

    project {

        jdkName = langLevel

        languageLevel = langLevel

    }

}
As you can see the build.gradle file is almost self-explanatory. Groovy plugin is applied to compile groovy code. It needs groovy-all.jar - declared in version 2.0 at dependencies block just next to Spock in version 0.7. What's most important, mentioned Maven repository URL is added at repositories block.

Project structure and execution

Gradle's default project directory structure is similar to Maven's one. Unfortunately there is no 'create project' task and you have to create it by hand. It's not a big obstacle though. The structure you will create will more or less look as follows: 
<project root>

│

├── build.gradle

└── src

    ├── main

    │   ├── groovy

    └── test

        └── groovy
To build a project now you can type command gradle build or gradle test to only run tests.

How about Java?

You can test native Java code with Spock. Just add src/main/java directory and a following line to the build.gradle: 
apply plugin: 'java'
This way if you don't want or just can't deploy Groovy compiled stuff into your production JVM for any reason, still whole goodness of testing with Spock and Groovy is at your hand.

A silly-simple example

Just to show that it works, here you go with a basic example.

Java simple example class:

public class SimpleJavaClass {


    public int sumAll(int... args) {


        int sum = 0;


        for (int arg : args){

            sum += arg;

        }


        return sum;

    }

}

Groovy simple example class:

class SimpleGroovyClass {


    String concatenateAll(char separator, String... args) {


        args.join(separator as String)

    }

}

The test, uhm... I mean the Specification:

class JustASpecification extends Specification {


    @Unroll('Sums integers #integers into: #expectedResult')

    def "Can sum different amount of integers"() {


        given:

            def instance = new SimpleJavaClass()


        when:

            def result = instance.sumAll(* integers)


        then:

            result == expectedResult


        where:

            expectedResult | integers

            11             | [3, 3, 5]

            8              | [3, 5]

            254            | [2, 4, 8, 16, 32, 64, 128]

            22             | [7, 5, 6, 2, 2]

    }


    @Unroll('Concatenates strings #strings with separator "#separator" into: #expectedResult')

    def "Can concatenate different amount of integers with a specified separator"() {


        given:

            def instance = new SimpleGroovyClass()


        when:

            def result = instance.concatenateAll(separator, * strings)


        then:

            result == expectedResult


        where:

            expectedResult     | separator   | strings

            'Whasup dude?'     | ' ' as char | ['Whasup', 'dude?']

            '2012/09/15'       | '/' as char | ['2012', '09', '15']

            'nice-to-meet-you' | '-' as char | ['nice', 'to', 'meet', 'you']

    }

}
To run tests with Gradle simply execute command gradle test. Test reports can be found at <project root>/build/reports/tests/index.html and look kind a like this.


Please note that, thanks to @Unroll annotation, test is executed once per each parameters row in the 'table' at specification's where: block. This isn't a Java label, but a AST transformation magic.

IDE integration

Gradle's plugin for Iintellij Idea

I've added also Intellij Idea plugin for IDE project generation and some configuration for it (IDE's JDK name). To generate Idea's project files just run command: gradle idea There are available Eclipse and Netbeans plugins too, however I haven't tested them. Idea's one works well.

Intellij Idea's plugins for Gradle

Idea itself has a light Gradle support built-in on its own. To not get confused: Gradle has plugin for Idea and Idea has plugin for Gradle. To get even more 'pluginated', there is also JetGradle plugin within Idea. However I haven't found good reason for it's existence - well, maybe excluding one. It shows dependency tree. There is a bug though - JetGradle work's fine only for lang level 1.6. Strangely all the plugins together do not conflict each other. They even give complementary, quite useful tool set.

Running tests under IDE

Jest to add something sweet this is how Specification looks when run with jUnit  runner under Intellij Idea (right mouse button on JustASpecification class or whole folder of specification extending classes and select "Run ...". You'll see a nice view like this.

Building web application

If you need to build Java web application and bundle it as war archive just add plugin by typing the line 
apply plugin: 'war'
in the build.gradle file and create a directory src/main/webapp.

Want to know more?

If you haven't heard about Spock or Gradle before or just curious, check the following links:

What next?

The last thing left is to write the real production code you are about to test. No matter will it be Groovy or Java, I leave this to your need and invention. Of course, you are welcome to post a comments here. I'll answer or even write some more posts about the subject.

Important update

Spock version 0.7 has been released, so the above build file doesn't work anymore. It's easy to fix it though. Just remove last dash and a word SNAPSHOT from Spock dependency declaration. Other important thing is that now spock-core depends on groovy-all-2.0.5, so to avoid dependency conflict groovy dependency should be changed from version 2.0.1 to 2.0.5.
Besides oss.sonata.org snapshots maven repository can be removed. No obstacles any more and the build file now looks as follows: 
apply plugin: 'groovy'

apply plugin: 'idea'


def langLevel = 1.7


sourceCompatibility = langLevel

targetCompatibility = langLevel


group = 'com.tamashumi.example.testwithspock'

version = '0.1'


repositories {

    mavenLocal()

    mavenCentral()

}


dependencies {

    groovy 'org.codehaus.groovy:groovy-all:2.0.5'

    testCompile 'org.spockframework:spock-core:0.7-groovy-2.0'

}


idea {

    project {

        jdkName = langLevel

        languageLevel = langLevel

    }

}