Friday, February 1, 2013

Reverse Engineering the Dartmouth Nutrition Menu Pt 1

This is an interesting project. I have been experiencing this problem with weight gain at the gym. I know if I don't eat enough food, I won't be able to lift as much and see results. Thinking that we naturally optimize what we measure, I thought it would be cool to create a food diary that scrapes information from the Dartmouth Nutrition Menu.

I would be able to document what I'm eating and see the associated macronutrients at the end of every meal. I could set my own calorie goals through certain foods and optimize that process. This would personally translate to seeing progress at the gym.

Here is the project: https://github.com/deloschang/foco-nutrition-scraper

--

Understanding how the nutrition menu works is the first priority. On the surface, it would appear that the macronutrients listed on the menu are images. Viewing the source only shows convoluted javascript functions. When clicking on items on the nutrition menu, the server is polled by a JSON-RPC request and returns relevant information about the macronutrients: everything from calories to vitamin intake.

To get the nutrition menu, I copied the JSON-RPC request from FireBug and channeled it into a Python URLLib parameters. This returned a full JSON payload of the nutrients.

To grab the list of the day's meal, I do the same with different methods and parameters observed from Firebug. Now I have a list of the food items served that day and a way to grab nutrients for a specific item.

Next, understanding how to loop over all the nutrients and create a comprehensive list is practical. Together, I can loop over the list and scrape all the information I need, storing it in a separate database.

Then have an Android app poll for the data from my server and present it to the user with some UI. There can be input boxes next to each food item and users can enter in their food intake. The application can use the information to provide entire macronutrient statistics for the day. Then, for everyday, you can track your food consumption and potentially show you related graphs.

Once I create the app, I should hedge against polling the server with too much traffic and instead move the data on my own server. Then, when students access the data, I can handle the traffic load instead and my own application can poll by the server in small intervals by itself.


No comments:

Post a Comment