File

mod_log_http/mod_log_http.lua @ 5691:ecfd7aece33b

mod_measure_modules: Report module statuses via OpenMetrics Someone in the chat asked about a health check endpoint, which reminded me of mod_http_status, which provides access to module statuses with full details. After that, this idea came about, which seems natural. As noted in the README, it could be used to monitor that critical modules are in fact loaded correctly. As more modules use the status API, the more useful this module and mod_http_status becomes.
author Kim Alvefur <zash@zash.se>
date Fri, 06 Oct 2023 18:34:39 +0200
parent 4977:3bd725430f40
line wrap: on
line source

module:set_global();

local http = require "net.http";
local codes = require "net.http.codes";
local json = require "util.json";

local log = assert(io.open(assert(module:get_option_string("log_http_file"), "Please supply log_http_file in the config"), "a+"));
log:setvbuf("line");

local function append_request(id, req)
	local headers = {};
	for k, v in pairs(req.headers) do
		table.insert(headers, { name = k, value = v });
	end
	local queryString = {};
	if req.query then
		for _, pair in ipairs(http.formdecode(req.query)) do
			table.insert(queryString, pair);
		end
	end
	log:write("<<<", json.encode({
		id = id;
		type = "request";
		method = req.method;
		url = req.url;
		httpVersion = "HTTP/1.1";
		cookies = {};
		headers = headers;
		queryString = queryString;
		postData = req.body and {
			mimeType = req.headers["Content-Type"];
			text = req.body;
		} or nil;
		headersSize = -1;
		bodySize = -1;
	}), "\n");
end

local function append_response(id, resp)
	local headers = {};
	for k, v in pairs(resp.headers) do
		table.insert(headers, { name = k, value = v });
	end
	log:write(">>>", json.encode({
		id = id;
		type = "response";
		status = resp.code;
		statusText = codes[resp.code];
		httpVersion = resp.httpversion;
		cookies = {};
		headers = headers;
		content = resp.body and {
			size = #resp.body;
			mimeType = resp.headers.content_type;
			text = resp.body;
		} or nil;
		headersSize = -1;
		bodySize = -1;
	}), "\n");
end

module:hook_object_event(http.events, "request", function (event)
	module:log("warn", "Request to %s!", event.url);
	append_request(event.request.id, event.request);
end);

module:hook_object_event(http.events, "request-connection-error", function (event)
	module:log("warn", "Failed to make request to %s!", event.url);
end);

module:hook_object_event(http.events, "response", function (event)
	module:log("warn", "Received response %d from %s!", event.code, event.url);
	append_response(event.request.id, event.response);
end);

function module.unload()
	log:close();
end