This is an application that I built for a client from September 1st 2021 to October 5th 2021. The client directed the development, and I worked along with them to build the end product. The project was initially cancelled, however we started working on it again after a few weeks around October 2nd. Our main goal for this project was to create an app for the popular social messaging app Discord that would check for updates on AO3 and notify you. AO3 is a non-profit open source website where you can share fictious stories about movies, shows, books etc.
The bot is very simple to start using, all you need is a Discord account and a Discord Server in which you have enough permissions to invite users/bots. After adding the bot to a server through this link, you can access all of its commands using ^help. To add a work, you just simply paste the desired work's url after calling ^add_work. This adds the work to the database and from now on it will be periodically checked for updates every 5 minutes.
To view all of your saved works, you can simply type ^get_all_works. This will display every single work you've saved, and also display their ID's so that you can also remove them if you want to.
One major challenge that I faced while building this app was figuring out how to periodically check for updates on every work. For this, I had to first figure out a database table setup that would fit the desired effect. I quickly came up with a solution, and created a table as such:
| works | values |
|---|---|
| id | integer |
| work_id | integer |
| chapters | integer |
| server_id | big_int |
| channel_id | big_int |
| user_id | big_int |
The update-checking works by initially saving the fetched chapter count to the database, and then fetching the chapter count again every 5 minutes and seeing if there's any changes, I initally wrote my own code for this, however after doing a bit of seraching I found that another person already built an API that fits the use of this proejct, so I used that instead. The update logic works like this:
- If the new chapter count is higher than the saved count, inform the user, and then update the saved record.
- If it's lower than the saved amount, this means a chapter was deleted, so silently update the count without informing the user.
- Else, if it's still the same, do nothing.
The final challenge I faced for this app was figuring out how to asynchnorously run the update checking function so that it wouldn't clog up the application. After quickly skimming through some documentation, I used the @tasks helper to set this up as such:
# Code for changing the applications status on Discord
@tasks.loop(minutes=5)
async def change_status():
await client.change_presence(activity=discord.Game(next(status)))
# Code for checking all works saved to the database for any updates
@tasks.loop(minutes=5)
async def check_update():
await check_all_for_update()I am currently planning on adding a function to search for works directly on Discord instead of having to get the URL from the browser, so that users can have a more easy and intelligible experience.
This app was built with Python and uses Discord.py and an AO3 API that was built by Armindo Flores.