Improving todo.txt & Todoist plugin

The GSoC coding period just ended. I would first like to apologize for not updating about my work. I am working on improving Todo.txt and Todoist integration to GNOME To Do. During the coding period, a lot of improvements were added to Todo.txt and Todoist and in this blog post I write about my journey and describing the implementation details.

Todo.txt & Todoist Updates

For those not familiar with todo.txt, it is a text-based format for storing and Todoist is quite a popular task manager application that can be used on smartphones as well as Personal Computers.

My aim for the Todo.txt was to improve the current code, make the plugin feature similar to To Do and document the syntax of todo.txt. I was able to complete all the task.

  1. The first task was to implement the support for notes in the todo.txt plugin. Notes are basically a more lengthy description of the task. Since todo.txt format allows adding custom key: value pairs for task description, I introduced a new key “note” and the value follows the key in quotes “”.  The only major challenge was handling the quotes and special characters like newlines, quotes etc in the description. This was done storing the notes in escaped form (i.e adding an extra ‘/’ before the special character and removing it during parsing phase.
  2. Adding support for creation and completion date –  The completion date occurs just after priority and creation date occurs after the completion date as per the todo.txt format. i.e x (priority) completion-date creation-date. Parsing completion-date & creation was easy using the last seen token. I had to subclass GtdTask into GtdTodoTxtTask since we need support for setting creation date. As the task are stored as text, the creation date needs to be cached and set at first load. This was done by subclassing GtdTask and adding a setter for the completion date.
  3. Adding support for list background – I noticed that list background color was not being cached into todo.txt and hence the color was lost on exit and start of To Do. After discussion with my mentor we decided to add two hidden custom lines in todo.txt, here hidden just means a marker “h:1” at the start of the line in todo.txt and are used to denote ToDo specific features. 1 custom line for storing list background color and other for storing Lists. Below is an example. For this task, I had to change the parser a bit. It was slightly confusing at first because I didn’t have a clear understanding of function pointers (needed for parser vtable implementation) but feaneron helped me with it.
      h:1 Lists @test @test2
      h:1 Colors test:#729fcf test2:#5c3566
  4. And now the most important task was to implement the subtask feature. The subtask was supported in the initial stage of the plugin but was removed because of instability. It wasn’t very clear to me as to how to go about but eventually, we decided to use indentation to denote parent-child relation between task described in immediate lines. An indentation of 4 spaces means the task is a child of the previous task. The algorithm works by creating all the task and maintaining it in a hastable with key as list of tasks. Once all the tasks are created the subtask relation is determine using the indentation property.
  5. Finally I documented the syntax of todo.txt so that new user find it easier to use the plugin. The documentation is present here.

With these changes todo.txt is much more stable and has all the feature that ToDo supports. Todoist had 3 major work to be done, fixing the network issue, auto sync of tasks and removing GOA and making Todoist plugin handle accounts on it’s own.

  • The network connectivity issue was handled by adding a network monitor and listening the network changes. Incase To Do cannot connect to the Todoist the provider is removed and hence no data loss happens due to user changes. The below screenshot show that wifi connectivity loss/gain is now handled by Todoist.
  • Peek 2018-08-06 23-39
  • The autosync patch is not merged yet but is very close to being merged in master. To reduce the number sync request with Todoist we manage time intervals at which to sync based on user window focus. When user focusses on Todoist for first time, sync request is generated immediately and timeout is set to 30 seconds. But if the focus is not on ToDo, the timeout is set to 10 minutes.
  • The final work is to making Todoist plugin handle it’s own accounts by using Keyring to store tokens. This work is still in progress and unfortunately I wasn’t able to get it merged. I have added patches for changes to preferances panel and implementation of keyring but still to integrate both these changes and also make modifications to plugins and providers. I will continue working on this and finish the implementation.

Finally, I would really like to thank my mentor Feaneron for guiding me and helping me whenever I was stuck, reviewing my code which was filled with code style errors and being patient enough to keep reminding me about my mistakes. I would also like to thank GNOME for giving me this great opportunity.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s