Mission Statement

There exist proprietary shopping list apps (which shall not be named here) that have a viewer for the current offers at various grocery store chains.

This is a feature that has so far not been available in open-source shopping-list applications.

One main roadblock is the fact that all stores use different implementations of their online flyers, creating a massive implementation and maintenance workload for the developers of such apps, should they consider such a feature.

It is the mission of the Cata-Log project to change this status quo.

Cata-Log’s main component is a server with interfaces for a multitude of digital flyer implementations. It regularly retrieves and caches the online flyers from user-selected providers. This data is then offered to third-party applications via a consistent, unified and comprehensive API.

This way, the load of implementing and maintaining the various interfaces to the online flyers is distributed onto the shoulders of the Cata-Log contributors, instead of a single developer.

To further the ease of adaption for third-party developers, the Cata-Log project includes client-libraries to its API for various languages, including Java and Swift for mobile- as well as Javascript for web-development.

Adding new flyer providers to Cata-Log is designed to be as easy as possible. A provider interface is defined by a single Python3 class. The documentation gives an extensive example and guideline for its implementation.

It’s the ultimate goal of the Cata-Log project to have a viewer for current store offers in the major open-source shopping-planning applications.