heka nginx_stub_status decoder

nginx_stub_status.lua

-- This Source Code Form is subject to the terms of the Mozilla Public
-- License, v. 2.0. If a copy of the MPL was not distributed with this
-- file, You can obtain one at http://mozilla.org/MPL/2.0/.

--[[


--]]

local l = require 'lpeg'
l.locale(l)

local sp = l.S(' \n\t')^0
local num = l.digit^1
local headings = l.P'server accepts handled requests'

function column(tag)
  return sp * l.Cg(num / tonumber, tag)
end

local act_conn = l.P'Active connections:' * column('connections')

local reading = sp * l.P'Reading:' * column('reading')
local writing = sp * l.P'Writing:' * column('writing')
local waiting = sp * l.P'Waiting:' * column('waiting')

local fmt = act_conn * sp * headings * column('accepts') * column('handled') *
            column('requests') * reading * writing * waiting

local grammar = l.Ct(fmt)

local payload_keep = read_config("payload_keep")

local msg = {
    Type = 'nginx_stub_status',
    Payload = nil,
    Fields = nil
}

function process_message()
    local data = read_message('Payload')
    msg.Fields = grammar:match(data)

    if not msg.Fields then
        return -1
    end

    if payload_keep then
        msg.Payload = data
    end

    msg.Fields.StatusCode = read_message("Fields[StatusCode]")
    inject_message(msg)
    return 0
end

nginx_stub_status_input.toml:

[nginx_stub_status_input]
type = "HttpInput"
url = "http://localhost:8090/nginx_status"
ticker_interval = 1
success_severity = 6
error_severity = 1
decoder = "nginx_stub_status_decoder"

nginx_stub_status_decoder.toml:

[root@app01.stage heka]# cat nginx_stub_status_decoder.toml 
[nginx_stub_status_decoder]
filename = "lua_decoders/nginx_stub_status.lua"
type = "SandboxDecoder"

[nginx_stub_status_decoder.config]
payload_keep = false

working on upstreaming: mozilla-services/heka#1636