Ocelot Graceful Load Balancer

What is it?

A Provider for Ocelot which provides a Round Robin Load Balancer with API Nodes Health Checking.

Status

The provider is in alpha stage but should be usable. It has been tested as part of my cluster setup.

This project is open to pull requests.

Setup

The setup is comparable to other Ocelot providers. Its target framework is netcoreapp3.1.

Install nuget package

dotnet add package Ocelot.GracefulLoadBalancer --version 0.0.2-alpha

or visit the nuget for other options on: https://www.nuget.org/packages/Ocelot.GraceFulLoadBalancer

Adding the provider to your project

The following shows a typical configuration a cluster for a 3 Node API Endpoint setup on the balancer and should be easily adaptable to your own settings. I assume you already have basic knowledge of Ocelot. Note! That I am using the YAML Configuration provider from NetEscapedes in the sample project instead of configuring via JSON. If you prefer JSON it should be easy to convert it manually or with a YAML to JSON converter.

Consider the following configuration:

Routes:
- DownstreamPathTemplate: "/api/auth/{everything}"
  DownstreamScheme: http
  DownstreamHostAndPorts:
  - Host: 192.168.178.88
    Port: 8800
  - Host: 192.168.178.90
    Port: 8800
  - Host: 192.168.178.91
    Port: 8800
  LoadBalancerOptions:
    Type: GracefulLoadBalancer
  UpstreamPathTemplate: "/api/auth/{everything}"
  UpstreamHttpMethod:
  - Get

The LoadBalancer options simply point to the implementation. You can add the loadbalancer as follows:

builder.ConfigureServices(s => {
    s.AddOcelot().AddGracefulLoadBalancer();
})

View the sample ApiGateway for starting up an entire gateway.