Yii And Node.js

Dear Members,

We have a web application (in the education sector) with two components - user registration and content. The educational content is display-only and is driven by db rules/entries. The entire website is written using the Yii framework.

We need to add code to track user-activity (login, time spent, test taken, marks scored etc etc) and are considering the possibility of writing this code using node.js + MongoDb (and also re-writing the user registration/management).

Is this feasible? Is this advisable? If not, then we would appreciate more details on why not to do it this way?