haproxyctl

README

haproxyctl

HAProxyCTL is a small Golang library for retriving the control settings from a haproxy instance over HTTP (not over a Unix socket, as other projects do), using HAProxy's built-in stats web interface.

It is used for querying remote HAProxy instances, and can send server actions such as putting a server into maintenance, or disabling health checks.

For details about usage, including commands, see the GoDoc documentation.

• haproxyctl
  • Example usage
    • Discovering HAProxy statistics
    • Performing a HAProxy action command
  • Example program

Example usage

Discovering HAProxy statistics

package main

import (
	"fmt"
	"net/url"
	"strings"

	"github.com/mhenderson-so/haproxyctl/cmd/haproxyctl"
)

func main() {
	//Create a simple URL to our HAProxy endpoint
	endpoint, _ := url.Parse("http://10.1.8.20:7003/")
	//Create our config item. We could specify our username/password here, but we will specify it encoded later on
	thisConfig := haproxyctl.HAProxyConfig{
		URL: *endpoint,
	}
	//Pass through our encoded username/password
	err := thisConfig.SetCredentialsFromAuthString("dXNlcm5hbWU6cGFzc3dvcmQ=")
	if err != nil {
		fmt.Println(err)
		return
	}

	//Get the latest statistics from this HAProxy server
	stats, err := thisConfig.GetStats()
	if err != nil {
		fmt.Println(err)
		return
	}

	//Print the output to the console in a readable format
	for _, x := range *stats {
		data := strings.Replace(fmt.Sprintf("%+v\n", x), " ", "\n\t", -1)
		fmt.Println(data[1 : len(data)-2])
		fmt.Println()
	}
}

Performing a HAProxy action command

package main

import (
	"fmt"
	"net/url"

	"github.com/mhenderson-so/haproxyctl/cmd/haproxyctl"
)

func main() {
	//Create a simple URL to our HAProxy endpoint
	endpoint, _ := url.Parse("http://10.1.8.20:7003/")
	//Create our config item. We could specify our username/password here, but we will specify it encoded later on
	thisConfig := haproxyctl.HAProxyConfig{
		URL: *endpoint,
	}
	//Pass through our encoded username/password
	err := thisConfig.SetCredentialsFromAuthString("dXNlcm5hbWU6cGFzc3dvcmQ=")
	if err != nil {
		fmt.Println(err)
		return
	}

	//Put these two servers into the "ready" state
	servers := []string{
		"ny-web01",
		"ny-web02",
	}
	done, _, err := thisConfig.SendAction(servers, "prod_web_tier", haproxyctl.ActionSetStateToReady)
	if err != nil {
		fmt.Println(err)
		return
	}

	if !done {
		fmt.Println("not ok")
		return
	}
	fmt.Println("ok")
}

Example program

There is a small example program contained in the root directory that can perform the haproxy commands exposed by haproxyctl. You can build with go build. You will need to edit the supplied example config.toml with your haproxy environment.

Usage: haproxyctl [-config config.toml] action server1,server2 backend
    -config config.toml - Optional parameter to the configuration file for your haproxy nodes
    action - the action to perform (see below for valid actions)
    server1,server2 - A comma-seperated list of back-end servers to perform the action on
    backend - The name of the backend to apply the action to

Example: haproxyctl get
Example: haproxyctl ready ny-web01,ny-web02 prod-web

Valid actions are:
    get      - Gets the status of the backends. No additional arguments are required
    ready    - Sets the server state to 'ready'
    drain    - Sets the server state to 'drain
    maint    - Sets the server state to 'maintenance'
    dhlth    - Disables health checks
    ehlth    - Enables health checks
    hrunn    - Forces the server to be UP
    hnolb    - Forces the server to disable load balancing
    hdown    - Forces the server to be DOWN
    dagent   - Disables agent checks
    eagent   - Enables agent checks
    arunn    - Forces agent to be UP
    adown    - Forces agent to be DOWN
    shutdown - Kills all sessions