/evs-notifications

EVS notifications for SUTD hostel

Primary LanguagePython

EVS Notifications System

Nobody wants their aircon to switch off in the middle of the night when their credit runs out.

The EVS notification system scrapes your credit balance daily. When your balance falls below a preset threshold, the system notifies you via Telegram bot.

Architecture

Click here for an image of the system architecture.

All operations involving data is done through individual corresponding APIs.

Components

  • Postgres database
  • Vue website for dashboard analytics
  • Telegram bot

APIs

  • CRUD operations for database
  • GET operations only for dashboard
  • Endpoint for fetching balance via web scraping
  • Endpoint for sending one-time messages via Telegram bot

Daily-run services

  • Scrape all user balances and add to database
  • Retrieve all users to notify and send notifications

Pre-requisites

  1. Python 3.6+
  2. Either:
    • Postgres 9.5
    • Docker
  3. NodeJS

Deployment

Python

The following components use Python:

  • APIs (Flask)
  • Telegram bot (python-telegram-bot)
  • Daily-run services

All Python-based components have a requirements.txt file in their corresponding folder.

Vue dashboard

There is a corresponding README in the dashboard folder. A static site is bundled using Webpack and used for hosting.

Postgres

The database is run from a Docker container. To get a database up and running on your local machine:

docker pull postgres:9.5
docker run --rm -d \
    --name pg-docker \
    -e POSTGRES_USER=ubuntu \
    -e POSTGRES_PASSWORD=password \
    -e POSTGRES_DB=evs \
    -p 5432:5432 \
    -v $HOME/docker/volumes/postgres:/var/lib/postgresql/data \
    postgres:9.5

Afterwards, to connect to the database:

PGPASSWORD=docker psql -h localhost -U postgres -d evs

For first-time setup, run \i create_tables.sql to define database schema.