In the summer of 2014, I took part in the CERN openlab Summer Student programme, for which I worked on a mobile app for the Invenio document repository, the open-source system behind the CERN Document Server. I gave a lightning talk about it, which won third prize on the programme!

Invenio is a Web service written in Python and Flask, which allows users to publish, browse and download papers or other documents. A prototype had been created for a mobile app which would allow users to browse Invenio repositories. My objectives were to improve its speed, functionality and usability, either by building on the prototype or starting over. I chose to start over, due to the large differences in architecture and chosen frameworks.

The app was built using Apache Cordova, a hybrid app framework which allows HTML5 apps to be wrapped and deployed to Android, iOS and many other platforms. This is very useful for building simple cross-platform apps, but raises interesting security issues, as Cordova apps are vulnerable to Cross-Site Scripting. The Invenio app was to display content differently depending on which server it was connected to, meaning that I had to create a simple way to customise the display of records without using HTML (which could contain malicious scripts from a compromised server).

Within the Cordova framework, I used jQuery, JinjaJS for templates, and TaffyDB (a JavaScript database library for semi-structured data). I found the Ratchet CSS framework particularly useful for making the app look native on both Android and iOS.