1. Building Spatial Web Services
with MongoDB + NodeJS in
Less than 30 Minutes
Steven Citron-Pousty
PaaS Dust Spreader, Red Hat
@TheSteve0
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2. Agenda
• Learn a little spatial
• Load some spatial data into mongo
• Do a query or two
• Repo for today’s code is here –
https://github.com/openshift/openshift-mongo-node-
express-example
SIGN UP CODE:
jseverywhere
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3. Assumptions
1) You already know that Node.JS + Mongo is like
chocolate and peanut butter
2) You can use the command line
3) You are comfortable with Mongo command line
4) Please ask questions – though since we only have 30
minutes they may have to wait until the end or after
the session
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4. What is OpenShift?
Red Hat’s free platform as a service for applications in the cloud.
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5. 5
Dalbera on Flickr

6. Kind of like Amazon, right? Nope.
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7. Cook24v on Flickr
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8. 8

9. What’s supported?
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10. There’s more? What’s the catch?
• OpenShift is free-as-in-beer & free-as-in-freedom
• Three 512 MB RAM / 1 GB storage gears
• Need more resources, just ask!
• We are really in Developer Preview
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11. On to spatial!
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12. Spatial is fun
The only spatial functionality Mongo currently has is:
1) Near
2) Containment
All of it is laid out on one page:
http://www.mongodb.org/display/DOCS/Geospatial+Inde
xing
First link on a google search for “mongodb spatial
indexing”
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13. Caveats
1. Assumes coords. are between -180 and 180
2. Can handle any 2D coordinates
3. Has methods to handle curvature of the earth
(spherical)
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14. How to make it work
1) Put your coordinates into an arrary
{ loc : [ 50 , 30 ] } //SUGGESTED OPTION
{ loc : { x : 50 , y : 30 } }
{ loc : { foo : 50 , y : 30 } }
{ loc : { lon : 40.739037, lat: 73.992964 } }
2) Make a 2d index
db.places.ensureIndex( { loc : "2d" } )
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15. Demo
1. I have an Node.JS app and a mongo instance running
2. Load some spatial data in JSON format
3. Make the 2d index
4. Do some fun spatial and MongoDB work
5. Show you the web services
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16. Conclusion
1. Spatial is easy and fun on Mongo
2. You can now build your own FourSquare or other
checkin application.
3. You can also build your own field data entry system.
4. You can build and deploy your application quickly
without having to think about infrastructure.
SIGN UP CODE:
jseverywhere
http://openshift.redhat.com
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