haproxy-spoa-do-resolve

SPOE Agent (SPOA) for HAProxy to perform DNS resolutions at runtime

This Agent performs DNS requests that HAProxy will ask it to do. It embeds for now 2 engines for A and PTR resolutions.

You can customize spoe-message for each engine with the event and the args to be sent. You can't change the name of the arg, only its value.

The file spoa-do-resolve.conf provided in this repo shows configuration example to use this agent. Corresponding HAProxy configuration is also provided.

This is recommended to use with HAProxy 2.0+.

Testing

First, do the go get thing.

You can easily test the solution using 3 shells:

1. run the agent: make run
2. run haproxy: haproxy -d -f ./haproxy.cfg
3. run curl against HAProxy and observe the result in the log line sent to stdout

Building

First, do the go get thing, then simply run make build

Help

Currently supported command line arguments:

Usage of ./spoa-do-resolve:
  -debug
        turn on debug messages

Known errors or limitations

None or check issues of this project.

TODO

• command line argument (flag) for:
  • custom DNS servers (default uses the OS ones)
  • files for Debug, Info, Warning and Error functions
• allow HAProxy to send a list of DNS server IPs to use for this request
• new SPOE engine for "full A+PTR" resolution
• cache the DNS respones in the agent