Table of Contents mGraffiti What is this? What does it do? What is it built with? How do I run this thing? REST API

mGraffiti

What is this?

This is the server backend for the Futurice mGraffiti project. mGraffiti is a service that took part in the Nokia World 2011 Hackathon event, with both Windows Phone 7 and QT mobile client versions. It won the best QT app prize. The backend is a couple of days worth of work - with a few more to add some (Spock/Geb) tests and perform a bit of refactoring.

The application is running here, if you want to check it out, although the web page isn't much to look at.

What does it do?

The app is essentially a 'virtual toilet wall', on which users can paint using the mobile clients. More technically, using a REST-lite JSON API, you can:

• Create new walls, and associate them with lat/lon coordinates and/or a NFC tag. (For the initial version, all walls are given a preset background image - custom background can be easily supported.)
• Query for walls by proximity or NFC tag.
• Get the images for the walls.
• Add an image layer to a wall.

There is also a quick'n'dirty web page (linked above), where you can view the walls created. But really, you'll want to download the QT or WP7 apps.

What is it built with?

Currently:

• Grails 2.0.1.
• MongoDB 2.0.1.
• A bunch of Grails plugins.

How do I run this thing?

Download the dependencies above, install them on a given machine, and run 'grails run-app' - you should have a working instance of the backend app. Why? Might be useful for learning MongoDB/Grails/Spock/Geb... Also feel free to create your own clients if you wish!

To run the tests, it's easiest to run 'grails dev test-app :spock'. To generate a CodeNarc report, 'grails codenarc' - although the ruleset doesn't fully support Grails 2.0.

REST API

The meat and potatoes of the application.

• GET /rest/wall?lat=61.12&lon=26.16&radius=100: list walls near location (with optional max distance in km)
• GET /rest/wall?nfcId=abc123: get wall by NFC tag ID
• GET /rest/wall/:wallId/image: get (flattened) image for wall as PNG, without background (only transparency)
• GET /rest/wall/:wallId/webImage: get (flattened) image for wall as JPG, with background
• POST/PUT /rest/wall/:wallId/image: add layer to wall image (PNG in request body, must match dimensions of background image - 2000x800 px for now)
• POST/PUT /rest/wall: create wall. Data as application/json payload in request, e.g.: {"title": "test", "creatorName": "dudeman12", location: {"lat":12.132, "lon":13.456}, "nfcId": "nfcTagGoesHere"}