Stream logs in an HTTP format from section.io platform (Use cases - External log storage, Machine learning, data processing etc)

Log Streaming with LUA

--Requires section.io OpenResty module
--Requires an "Alternate Origin" configured that points to an HTTP log ingestion endpoint: https://www.section.io/docs/how-to/multiple-origins/
--There are several files that need to be created in the "openresty" folder in the section.io configuration. Recommend cloning the git repository from "Advanced Config" menu in section.io portal.

--server.conf should contain:
location / {

  #https://github.com/openresty/lua-nginx-module#log_by_lua_file
  log_by_lua_file /opt/proxy_config/log.lua;

  proxy_pass "http://next_hop_upstream";
}

--init.lua should contain the following to gather the correct next-hop IP for the nginx subrequest we make later:

    -- Configure `require()` to find custom Lua modules
    package.path = package.path .. ";/opt/proxy_config/?.lua"

    local hostsFile = io.open("/etc/hosts", "r")
    
    nextHop = "1.1.1.1"
    
    for line in hostsFile:lines() do
        local etcHostsEntry = line:match("(%d+%.%d+%.%d+%.%d+).*next%-hop")
        
        if etcHostsEntry then
          nextHop = etcHostsEntry
        end
    
    end

    ngx.log(ngx.ERR, "Final next-hop value: ", nextHop)
    
    hostsFile:close()
    
 --log.lua, Generates the Async HTTP request that is streamed and defines content. The file should contain:
    local http = require ("http")

    local function push_data(premature, uri, args, status, nextHopIP)

        --Default variables
        uri = uri or ""
        args = args or ""
        status = status or ""
    
        local httpc = http.new()

        --Example using Sumo Logic, Adjust to your requirements (Adjust request_uri function,HTTP header: Host, HTTP header: section-origin and the "body" to contain the data you want to send)
        local res, err = httpc:request_uri("http://" .. nextHopIP .. "/receiver/v1/http/YOURENDPOINTDETAILHERE", {
            method = "POST",
            ssl_verify = false,
            headers = {
                ["Accept"] = "*/*",
                ["Host"] = "collectors.au.sumologic.com",
                ["section-origin"] = "log_streaming_endpoint",
                ["X-Forwarded-Proto"] = "https",
            },
            body = [[{data:{"url": "]]..uri..[[", "args": "]]..args..[[", "status": "]]..status..[["}}]]
        })

        if not res then
            ngx.log(ngx.ERR, "Log Stream Call failed : ", err)
            return
        end

     end

     local ok, err = ngx.timer.at(0, push_data, ngx.var.uri, ngx.var.args, ngx.status, nextHop)
     if not ok then
        ngx.log(ngx.ERR, "failed to create timer: ", err)
        return
     end
 
 -- Include the file http.lua and http_headers.lua inside the openresty folder. Source: https://github.com/pintsized/lua-resty-http