HAMerger is simple script built with node.js and inspired by Josip Lazić article.
HAMerger allows you to merge multiple configuration files into a single one readable by HaProxy. This script is able to concat configuration of a same section from different files into the right place.
Below are the available options :
Usage: ./hamerger.js [options] <configPath>
Options:
-V, --version output the version number
-f, --filter <filter> The filter to apply on config file. Default to ".cfg$"
-p, --print Print merged config
-o, --output <path> The output file to write merged config
-v, --verbose Print logs
-h, --help output usage information
Assuming the config files and structure below, you can use the script like this : /hamerger.js /etc/haproxy/conf.d -o /etc/haproxy/haproxy.cfg -v.
/etc/haproxy/conf.d/
├── 000-global.cfg
├── 001-vm1.cfg
├── 002-vm2.cfg
└── 999-default.cfg
/etc/haproxy/conf.d/000-global.cfg:
frontend dev
bind 127.0.0.1:80
/etc/haproxy/conf.d/001-vm1.cfg:
frontend dev
acl is_vm1 hdr(host) -i vm1.mycompany.com
use_backend vm1_backend if is_vm1
backend vm1_backend
server vm1 172.21.0.11:80 check
...
/etc/haproxy/conf.d/001-vm2.cfg:
frontend dev
acl is_vm2 hdr(host) -i vm2.mycompany.com
use_backend vm2_backend if is_vm2
backend vm2_backend
server vm1 172.21.0.12:80 check
...
/etc/haproxy/conf.d/999-default.cfg:
frontend dev
default_backend fallback_backend
backend fallback_backend
server fallback 172.21.0.1:80 check
...
The generated file : /etc/haproxy/haproxy.cfg
frontend dev
bind 127.0.0.1:80
acl is_vm1 hdr(host) -i vm1.mycompany.com
use_backend vm1_backend if is_vm1
acl is_vm2 hdr(host) -i vm2.mycompany.com
use_backend vm2_backend if is_vm2
default_backend fallback_backend
backend vm1_backend
server vm1 172.21.0.11:80 check
...
backend vm2_backend
server vm2 172.21.0.12:80 check
...
backend fallback_backend
server fallback 172.21.0.1:80 check
...