1. Bring Spatial Love to your Java
Application
Shekhar Gulati
@shekhargulati
OpenShift Evangelist, Red Hat
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2. Building A Location Aware Job Search App
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3. User Stories

As a User, I should be able to find all the jobs.

As a User, I should be able to find all the jobs near to
my location.

As a User, I should be able to find all MongoDB (or
any skill) jobs near to my location.

As a User, I should be able to find all the MongoDB (or
any other skill) jobs near to my location with distance.
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4. Assumptions: as a developer ...

Want to prototype quickly

Need quick feedback

Don't want to manage infrastructure

Don't want to spend much money on infrastructure. Or, even
better, you want it to be free.

Use your existing knowledge

Should be able to use the best tool for the job
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5. Technology Choices

MongoDB

OpenShift

Java 6

Spring 3.1.2.RELEASE

Spring 1.1.0.M1

GIT

SSH
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6. Why MongoDB ?

Easy to get running

Open Source

Active community

Rich documents

Geospatial indexing.

Writes are very fast. You can customize it using
WriteConcern.
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7. Rich Document
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8. Geospatial Indexing Basics

What is it for?

Find all the MongoDB jobs near me

Find all the MongoDB jobs within Pune

Supports only two dimensional indexes.

You can only have one geospatial index per collection.

The spatial functionality MongoDB currently has is:

Near

Containment
http://www.mongodb.org/display/DOCS/Geospatial+
Indexing
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9. How to make it work
1) Put your coordinates into an array
{ loc : [ 50 , 30 ] } //SUGGESTED OPTION
{ loc : { x : 50 , y : 30 } }
{ loc : { foo : 50 , y : 30 } }
{ loc : { lon : 40.739037, lat: 73.992964 } }
1) Make a 2d index
db.places.ensureIndex( { loc : "2d" } )
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10. Why OpenShift ?

Supports MongoDB. Also supports MySQL and
PostgreSQL.

Multi-language support. Supports Java, Node.js, Perl,
Python, PHP and Ruby.

No need to learn anything new.

Scalable.

FREE!
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11. 11

12. What else do I get and what is the
catch?
• OpenShift is free-as-in-beer & free-as-in-freedom
• You get three free gears, each with 512MB memory
and 1GB of disk space.
• Need more resources, just ask!
• The catch is we are in developer preview right now
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13. Let's get our hands dirty
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14. Create an OpenShift Account
https://openshift.redhat.com/app/account/new
Promo code is bangalore
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15. Installing Client Tools
Install Ruby 1.8.7 or greater
Install Git
Install rhc OpenShift gem
Refer to documentation
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16. Setup your OpenShift Environment
rhc setup -l <openshift_login>
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17. Creating an OpenShift Application
rhc app create -a localjobs -t jbossas-7 -d
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18. Adding MongoDB and RockMongo
Cartridge
rhc app cartridge add -a localjobs -c mongodb-2.0
rhc app cartridge add -a localjobs -c rockmongo-1.1
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19. Play with MongoDB running in the Cloud
ssh into instance
Type mongo on the shell
Create a sample db
Insert some documents in the collection
Run some queries
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20. Let's take a look at GIT
Distributed version control
A local repository – on your laptop
A remote repository – on some other machine, usually a
server
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21. You need to understand at least 3 commands in Git
1. Git add . (means add all news files as being tracked in
the local repository)
2. Git commit –am “your message” (means commit all
my changes to the local repository with this message)
3. Git push (means push from your local repository to the
repository on your OpenShift gear)
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22. Pulling the code from GitHub
git rm -rf src pom.xml
git commit -am “removed default files”
git remote add localjobs -m master
git://github.com/shekhargulati/localjobs.git
git pull -s recursive -X theirs localjobs master
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23. Importing Data into MongoDB
rhc app show -a localjobs -l <openshift_login_email>
scp -r jobs-data.json
<instance_ssh_access>:localjobs/data
ssh <instance_ssh_access>
mongoimport -d localjobs -c jobs --file jobs-data.json -u
$OPENSHIFT_NOSQL_DB_USERNAME -p
$OPENSHIFT_NOSQL_DB_PASSWORD -h
$OPENSHIFT_NOSQL_DB_HOST -port
$OPENSHIFT_NOSQL_DB_PORT
db.jobs.ensureIndex({"location":"2d"})
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24. Show some geospatial queries
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25. Deploy the code to OpenShift
git push
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26. Code Walkthrough
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27. Conclusion
1. MongoDB makes it very easy to build location aware
applications.
2. OpenShift is very easy to use and embraces rapid
development.
3. Did I mention – Free?
4. What are you waiting for? Try it out.
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