HAProxy combined with confd for HTTP load balancing

This is based on yaronr/haproxy-confd and cstpdk/haproxy-confd

• HAProxy 1.6.x with confd 0.12.0-alpha
• Uses zero-downtime reconfiguration (e.g - instead of harpy reload, which will drop all connections, will gradually transfer new connections to the new config)
• Added support for url rexeg (not reggae, damn you spell checker) for routing, in addition to the usual hostname pattern
• Added validation for existence of keys in backing kv store, to prevent failures
• Used official Alpine HAProxy as base to reduce the size of the image
• Added multiple domain support
• Added SSL/HTTPS support
• Added tests

Usage

Setup

Create the paths allowing confd to find the services:

etcdctl mkdir "/services"
etcdctl mkdir "/tcp-services"
etcdctl mkdir "/config"

Depending on your needs, create one or more services or tcp-services. For instance, to create an http service with domain example.org and load balancing on servers 1.2.3.4:80 (we'll call it nodeA) and 2.3.4.5:80 (called nodeB), run these commands:

etcdctl mkdir "/services/example.org"
etcdctl set "/services/example.org/upstreams/nodeA" "1.2.3.4:80"
etcdctl set "/services/example.org/upstreams/nodeB" "2.3.4.5:80"

Enable SSL/HTTP support

etcdctl mkdir "/config/services"
etcdctl set "/config/services/enable_ssl" "true"
etcdctl set "/services/example.org/scheme" "https"

Possible values for scheme are: http (default), https, http-and-https. If scheme is https, all traffic to http for the domain will be redirected to https.

Add pem certs/keys to keys directory to be mounted to the container.

Start Container

Start the container making sure to expose port 80 on the host machine

docker run -e ETCD_NODE=http://172.17.42.1:2379 -p 1000:1000 -p 80:80 -p 443:443 -v `pwd`/keys:/keys compass/haproxy-confd

To add an upstream node, let's say nodeB2, 2.3.4.5:90, you just have to run this, and the configuration should safely be updated !

etcdctl set "/services/example.org/upstreams/nodeB2" "2.3.4.5:90"

To remove an upstream server, let's say ... nodeB2 (added by mistake ?), just run

etcdctl rm "/services/myapp/upstreams/nodeB2"

To remove a service, and so a directory, you must type

etcdctl rmdir "/services/example.org"

The commands for a tcp-service are the same but with tcp-services instead of services