NarayanAdithya / KryptoBackendTask

Real-Time Cryptocurrency Monitoring

Kryptolert

About The Project

Developed using the Flask Framework and other flask extensions. The system I have developed consists of 3 servers. The first server handling the API requests and the other two servers handling the Mailing and Scheduler for checking the coin prices with the alerts. THe system makes use of PostGresQL and RabbitMQ to be more scalable. Since I am not that comfortable with docker and due to time constraints I was not able to setup the docker-compose.yml in time.

Build With

• Python
• RabbitMQ
• PostGreSQL

Packages Used

• Flask
• Flask-SQLAlchemy
• Psycopg2
• Flask-Mail
• Flask-Login
• Flask-Migrate
• Pika
• APScheduler

File Structure

/root -> Houses the Main API and the Mailing and Scheduler Services as 2 different folders

/root/mailer -> Mailing Service

/root/scheduler -> Schduler CRON Job that Checks the PostGresQL database for triggering any alerts

Usage

To run the code as of now first start the PostGres and RabbitMQ services. After that start the Main API followed by the scheduler and mailer services.

Requests to the API will create alerts:

• /auth/register - To create a user. email and password have to be passed in.
• /auth/login - Logs in valid users and returns token.
• /alerts/create - Creates a new alert
• /alerts/delete - Deletes an alert
• /alerts/fetch_all - Returns list of all alerts created so far
• /alerts/fetch_all/<FILTER> - Returns the list filtered by status, which can be one of "TRIGGERED", "CREATED", "DELETED"

Examples

Making an invalid login request

Making an account and retrieving the token

Making the Alert

Fetching Alerts

Email Triggered for Alert

Email Triggered By Mailing Service which was received from RabbitMQ

Updated Database

How to Run

• Setup a virtual environment and then run pip install -r requirements.txt in root folder
• Start PostgreSQL service with username as user and password as pass. If you have an existing server then just create an environment variable DB_URI as postgres://user:password@localhost:port
• For running main server set environment variable FLASK_APP as Krypto.py, while running the first time run the following commands flask db init, flask db migrate, flask db upgrade
• Now use python Krypto.py the server will start and the API is accessible at port 8000
• Start the RabbitMQ service using docker run -d --hostname my-rabbit --name some-rabbit -e RABBITMQ_DEFAULT_USER=user -e RABBITMQ_DEFAULT_PASS=password rabbitmq:3-management
• Now cd into scheduler service and start that service using python scheduler.py, this service wil fetch untriggered alerts and check if they have to be triggered, in that case a request is placed on the rabbit mq broker.
• Now cd into mailer folder and start the flask_mail.py service. This service listens to the RabbitMQ broker and processes or consumes the requests as they come in.
• The request is then printed onto the console.

Tasks Done

• Create API Endpoint for creating an alert
• Creating API Endpoint for deleting an alert
• Creating API Endpoint for fetching all alerts
• Creating API Endpoint to return alerts filtered by status
• Paginate the response
• Add User Authentication with JWT
• Make use of coingecko API for price checking
• Printing the mail procedure to console as google removed access to less secure apps for my account
• Adding a cache layer for the fetch_all endpoint
• Use PostGres
• Use RabbitMQ
• Bundle in Docker-Compose

Contact

Adithya Narayan - @a.dity.a_n.araya.n - [e-mail]