lua-haproxy

lua-haproxy provides:

a high-level Lua binding for the HAProxy stats interface
an embedded HTTP API that runs as a service inside HAProxy

Requirements

Linux
HAProxy 1.6+ with Lua support

To check if your version includes Lua, run:
```
haproxy -vv | grep Lua
```
HAProxy must run in single-process mode (default)
Lua 5.3 and Luarocks for development

Install

Clone the repo.

git clone https://github.com/benwebber/lua-haproxy

Install the rock.

luarocks install haproxy-scm-0.rockspec

Configure HAProxy to run the Lua service.

It might be convenient to run the API on a dedicated port:

global
  stats socket /run/haproxy/admin.sock mode 660 level admin
  lua-load /usr/local/bin/lua-haproxy-api

listen http
  bind *:8000
  mode http
  http-request use-service lua.haproxy-api

Embedded API

The main entry point for this package provides an embedded HTTP API. The API runs as a Lua service inside HAProxy. Use it to introspect the parent process.

Overview

Requests that create or modify resources should be encoded as JSON (Content-Type: application/json).

The API will return structured data as JSON, and unstructured data as plain text (Content-Type: text/plain).

Endpoints

`config`

METHOD	PATH	DESCRIPTION
`GET`	`/config`	Return the active configuration file in plain text.

`stats`

METHOD	PATH	DESCRIPTION
`GET`	`/stats`	Query the stats socket for process statistics.
`GET`	`/stats/backends`	Show statistics for all backends.
`GET`	`/stats/backends/:backend`	Show statistics for the named backend.
`GET`	`/stats/backends/:backend/servers`	Show statistics for all servers in the named backend.
`GET`	`/stats/backends/:backend/servers/:server`	Show statistics for the a specific server in the named backed.
`GET`	`/stats/backends/:backend/servers/:server/weight`	Get the current weight of a server.
`PATCH`	`/stats/backends/:backend/servers/:server/weight`	Set the weight of a server.
`GET`	`/stats/backends/:backend/servers/:server/state`	Get the current state of a server.
`PATCH`	`/stats/backends/:backend/servers/:server/state`	Set the state of a server.
`GET`	`/stats/info`	Query the stats socket for process info.
`GET`	`/stats/frontends`	Show statistics for all frontends.
`GET`	`/stats/frontends/:frontend`	Show statistics for the named frontend.

Documentation

Refer to the Lua API documentation for details:

https://benwebber.github.io/lua-haproxy/

Caveats

lua-haproxy is not production-ready. Both the internal Lua API and embedded HTTP APIs are unstable.

License

MIT