BAS use cases implementation structure

Use cases implementation for the BAS Project: This project serves as a template for creating use cases such as birthday or PTO notifications. It extracts information from a source like Notion and publishes it on a receiver like Discord with an specific schedule.

Project Requirements

• Ruby 3.2
• Node 18.13.0

Setup

Clone the repository

git clone [email protected]:kommitters/bas_serverless.git
cd bns_serverless

Install ruby dependencies

bundle install --path vendor/bundle

Build docker containers:

# Build containers: just first time
docker-compose up --build

# To start the containers
docker-compose up

Environment variables

Create the environment variables configuration file.

cp env.yml.example env.yml

On this file, you can add the environment variables depending on the environment you are in. For example, for a use case with Notion as a read and Discord as the process:

dev:
  NOTION_DATABASE_ID: NOTION_DATABASE_ID
  NOTION_SECRET: NOTION_SECRET
  DISCORD_WEBHOOK: DISCORD_WEBHOOK
  DISCORD_BOT_NAME: DISCORD_BOT_NAME
prod:
  NOTION_DATABASE_ID: NOTION_DATABASE_ID
  NOTION_SECRET: NOTION_SECRET
  DISCORD_WEBHOOK: DISCORD_WEBHOOK
  DISCORD_BOT_NAME: DISCORD_BOT_NAME

Schedule

For each use case, the bots schedules are configured on the schedule.sh script inside the CRON_JOBS tuple. Example:

CRON_JOBS=(
    "51 20 * * * fetch_pto_from_notion.rb"
    "52 20 * * * humanize_pto.rb"
    "53 20 * * * notify_pto_in_discord.rb"
    "54 20 * * * garbage_collector.rb"
)

To learn how to modify the cron configuration follow this guide: Schedule expressions using rate or cron

The environment variable should be defined with the quotes, specially if is set as a github secret. Example:

# Schedule definition
"0 13,15,19,21 ? * MON-FRI *"

Build a New Use Case

To add a new use case:

1. Define the Bots:

   • If the required bots are not already defined, create them in the src/implementations folder.

2. Model the Use Case:

   • In the src/use_cases_execution folder, create a new folder for the use case. This folder should:
     • Call the necessary bots from the implementations folder, modeling the use case and its specific parameters.
     • Contain a schedule.sh script where the cronjob schedules for the bots will be configured.

3. Update Shared Storage:

   • Define any new tables required for shared storage in the db/build_shared_storage.sql file.

To activate the cronjob on the docker container execute the update_container.sh script (this is executed each time the container is restarted):

docker exec bas_cronjobs bash /app/scripts/update_container.sh