Tracking Server Demonstration

Demonstration project for tracking users impressions when browsing through the web.

Overview

This project creates a web server application which captures, parses and stores HTTP requests' body contents into Apache Cassandra databases. The web server is built using the Go programing language and shipped as a Docker container to Kubernetes clusters - optimizing cost and performance.

The web server responds to the following endpoints:

Endpoint	Method
/	GET	Healtcheck
/track	POST	Data storing

For the /track endpoint, the application will expect a json containing the internet event data using the following pattern:

{
    "username": "John Doe",
    "target": "https://www.google.com/",
    "description": "VIEW"
}

There are two valid values for the description field: CLICK and VIEW. Any other values will trigger a BadRequest response, informing that the field's value is invalid.

Deployment

Both the application and database of this project are shipped as containers to Kubernetes clusters. One can recreate this infrastructure by using the .yaml files present in the k8s directory. The deploy creates a StorageClass, a PersistentVolumeClaim, and a StatefulSet with a headless Service for the database as well as a Deployment and LoadBalancer for the API.

Handling High Throughput of Tracking Events

Since we are dealing with the "whole" web, we can expect a high throughput of requests in our API. In the provided backend, there is a load balancer that can help us with that. In case the pods behind the load balancer aren't able to handle the incoming traffic, we can easily scale our application by increasing the replicas number of our Cassandra StatefulSet and of our Deployment.

Local Development

You can build and run the application locally using docker-compose. Install it and run the following command on the project's root directory:

docker-compose up --build

Even though the output is kind of strange, by the end there should be an local app listening to the 8080 port of your machine and a Cassandra standalone cluster listening to the port 9042 of your machine. At this point, if you want, you can run the unit and integration tests present in the project:

go test -v ./...

Possible Improvements

• Enable TLS connections
• Logging and monitoring