Load Balancing

Load Balancing

Load balancing multiple Echo servers using a reverse proxy server like Nginx, Armor

This recipe demonstrates how you can use Nginx or Armor as a reverse proxy server and load balance between multiple Echo servers.

How to setup Nginx proxy server with Echo?

Step 1: Install Nginx

https://www.nginx.com/resources/wiki/start/topics/tutorials/install

Step 2: Configure Nginx

Create a file /etc/nginx/sites-enabled/localhost with the following content:

upstream localhost {
  server localhost:8081;
  server localhost:8082;
}
server {
  listen          8080;
  server_name     localhost;
  access_log      /var/log/nginx/localhost.access.log combined;
  location / {
    proxy_pass      http://localhost;
  }
}

Change listen, server_name, access_log per your need.

Step 3: Restart Nginx

service nginx restart

Step 4: Start upstream servers

cd upstream
go run server.go server1 :8081
go run server.go server2 :8082

Step 5: Browse to https://localhost:8080

You should see a webpage being served from “server 1” or “server 2”.

Hello from upstream server server1

How to setup Armor proxy server with Echo?

Step 1: Install Armor

https://armor.labstack.com/guide

Step 2: Configure Armor

Create a file /etc/armor/config.yaml with the following content:

address: ":8080"
plugins:
- name: logger
hosts:
  localhost:1323:
    paths:
      "/":
        plugins:
        - name: proxy
          targets:
          - url: http://localhost:8081
          - url: http://localhost:8082

Step 3: Start Armor

armor -c /etc/armor/config.yaml

Change address and hosts per your need.

Step 4 & 5: Follow Nginx recipe

Source Code

upstream/server.go

package main
import (
    "fmt"
    "net/http"
    "os"
    "github.com/labstack/echo"
    "github.com/labstack/echo/middleware"
)
var index = `
    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <meta name="viewport" content="width=device-width, initial-scale=1.0">
        <meta http-equiv="X-UA-Compatible" content="ie=edge">
        <title>Upstream Server</title>
        <style>
            h1, p {
                font-weight: 300;
            }
        </style>
    </head>
    <body>
        <p>
            Hello from upstream server %s
        </p>
    </body>
    </html
`
func main() {
    name := os.Args[1]
    port := os.Args[2]
    e := echo.New()
    e.Use(middleware.Recover())
    e.Use(middleware.Logger())
    e.GET("/", func(c echo.Context) error {
        return c.HTML(http.StatusOK, fmt.Sprintf(index, name))
    })
    e.Logger.Fatal(e.Start(port))
}