Archive for December, 2012

MongoDB and Node.Js Tutorial

December 20, 2012

Quick post to link to an excellent tutorial on the Heroku website to use MongoDB as a database with Node.Js using the Mongoose library.

https://devcenter.heroku.com/articles/nodejs-mongoose

This is the exact same implementation that we used to build ThreatWiki with Mongoose. Quick and fast to implement.

One thing that surprised me about this guide is that it recommends to specify the option “safe” mode for the connection with mongoDB. The safe mode is the mode that guarantees that you will be informed by an error if a write to the database fails (in the default implementation of MongoDB it’s off by default to increase speed).

However, as we can read on Mongoose documentation page:

By default this is set to true for all schemas which guarentees that any error that occurs will get reported back to our method callback.

So the safe mode is already enabled by default by mongoose for every save on the database, so it doesn’t seem necessary to specify it like the tutorial is proposing.

Select2 javascript library with Bootstrap

December 5, 2012

I’m currently volunteering for The Sentinel Project on a genocide risk tracking and visualization platform named ThreatWiki built with node.js and mongoDB. Read more details about the launch on The Sentinel Project blog

One important feature in the frontend is the ability to add tags to datapoints created in the system. As we were testing locally in our environment, the typical multi-select input box looked like a good enough way to select tags.

Typical tag list

However after starting to import an Excel sheets that contains over 500 datapoints and over 50 different tags, it became clear that this way of selecting tags wouldn’t work well for the users. I decided to add the Select2 library that allow us to search across all the tags and will display the existing tag choices below.

Adding it to our existing codebase was very minimal work, I actually wish I did it before. My only concern was to know if it would play nice with our Bootstrap frontend framework. At first look it didn’t but adding “width: ‘resolve'” as option to select2 fixed it (see that issue on select2’s github). The result looks fantastic and easier to use by our users

Tag selection with Select2

Look at ThreatWiki on GitHub if you want to know more about the project!