http-load-balancer

An HTTP load balancer built using Go and the Gin framework, with support for multiple balancing strategies(round-robin, least connections, and sticky sessions).

Features

• Balancing algorithms
  • Round-robin
  • Least connections
  • Sticky sessions
• Backend Health Checks - Monitors backend health at regular intervals
• TLS Encryption - Secure communication between the clients and the load balancer
• Metrics Monitoring - Tracks incoming requestsand backend performance

Setup and Installation

• Prerequisites
  • Go 1.20+
  • OpenSSL(to generate certificates)
• Clone the Repository

git clone https://github.com/lokeshllkumar/load-balancer.git
cd load-balancer

• Install the Required Dependencies

go mod tidy

• Generate TLS Certificates
  • Create a directory called certs to store the certificate
  • Generate an RSA key

  openssl gen rsa -out key.pem 2048

  • Generate a CSR file to create a Certificate

  openssl req -new -key key.pem -out server.csr
  

  • Generate the Self-Signed Certificate

  openssl x509 -req -days 365 -in server.csr -signkey key.pem -out cert.pem

  • Verify the Certificate

  openssl x509 -in cert.pem -text -noout

• Build the Project

go build -o load-balancer .

• Run the server

./load-balancer

Usage

• Health Check Endpoint
  • Check if the server is running

  curl https://localhost:843/health --insecure

• Add a Backend Server
  • Add a backend server dynamically

  curl -X POST https://localhost:8443/api/backends -d '{"url": "https://backend3:8082"}' -H "Content-Type: application/json" --insecure

• List All Backends

  curl https://localhost:8443/api/backends --insecure

Load Balancing Strategies

• Round Robin
  • Distributes requests evenly across all available backends.
• Least Connections
  • Directs traffic to the backend with the fewest active connections.
• Sticky Sessions
  • Ensures requests from the same client are directed to the same backend.