chrislahaye / pm2-messages Goto Github PK

Not a pm2-messages issue, but significant enough to mention here. pm2-messages is vulnerable to pm2 bug 4627.

We've had to disable pm2-messages because pm2 keeps crashing/restarting when being scraped by multiple prometheus servers.

@ChrisLahaye I'd would love to know your thoughts on this issue or if you have ideas for a solution.

@ChrisLahaye hello again. For a little context, your pm2-messages is being used in CoStar Group's flagship product CoStar Suite.

We ended up having to disable prometheus scraping in production because of a memory leak.

This leak was traced back to pm2-messages. The leak is of an object containing pendingBusTargets, resolverBusTargets, and messages as you can see in this screenshot. A thorough memory analysis was performed to discover and confirm these findings.

A thorough analysis of the code confirmed that the leak is of the myBus Listener (myBus.on).

The following PR suggests a remedy by allowing the bus listeners to be destroyed after use.
#8

The project hasn't been updated in a while, is it possible to update dependencies to cover the vulnerabilities of the older dependency versions?

This appears to me like the best solution I've encountered so far for gathering prom-metrics from a clustered app in pm2. Unfortunately I can't get it to work. Could additional documentation/examples please be provided?

I run the following code against 4 clustered instances of an app hosted in pm2 4.4.0

import pm2mes from "pm2-messages";
import * as prom from "prom-client";

prom.collectDefaultMetrics();
pm2mes.onMessage("get_prom_register", () => prom.register.getMetricsAsJSON());

const foo = async (callback) => {
  const metricsArr = await pm2mes.getMessages("get_prom_register");
  console.log(metricsArr);
  callback(prom.AggregatorRegistry.aggregate(metricsArr).metrics());
};

foo((o) => console.log(o));

the result is ....

> [email protected] start /work/csgp/pm2-prom-client
> node ./dist/index.js

[]

Any hints as to why metricsArr is empty?

Regards