Ubuntu Touch Web App Plugins

Plugins to make Ubuntu Touch web apps work better with downloads.

The Ubport's mascot Yumi.

Over the past few weeks I’ve been working on some plugins for Ubuntu Touch web apps that work around some issues with the platform. The first plugin is BlobSaver. It saves data from blob urls that the download manager doesn’t know how to handle. If you are not familiar with blob urls (and I was not before this project), there is a brief overview on this Stack Overflow question. since blob urls look similar to normal urls the web browser or web app will pass the url over to the Ubuntu Touch download manager, but the download manager doesn’t know what to do with a blob url and it throws an error (and it’s not possible for it to know anything about the blob url because only the browser knows what data that url references). BlobSaver gets around this limitation by hijacking the blob url creation process and sending the raw data to a C++ function which then converts it into a file. That file then can be opened up in the content hub. You can see this in action with the Photopea Web App that I put together for another community member. BlobSaver overcomes a missing feature in the browser and is a hack. A real solution would be for the Ubuntu Touch web browser to have its own support for blob urls, but until then BlobSaver is here to save the day.

The other plugin that I have been working on is DownloadInterceptor. DownloadInterceptor overcomes a different problem with the Ubuntu Touch browser and download manager combo. This plugin is there to help you download files from sites with authenication. Without this plugin the browser or web app will pass a download url to the download manager, but if you need to be authenticated the download manager won’t be able to download anything. DownloadInterceptor works by preventing the download manager from getting the url and downloading the file itself (using the necessary cookies). The saved file then can be used in the content hub. You can see it in action on the newly developed Nextcloud web app. Including DownloadInterceptor in the Nextcloud web app allows you to download your files from Nextcloud (something that is impossible in the browser). This is not my app but I have contributed to its development.

If you have any questions about either plugin or need help integrating them into your webapp please don’t hesitate to contact me.