How to see PM2 logs of a process using PM2 API - node.js

Question

I am trying to get the PM2 logs in my backend server using PM2 API. I tried going through the docs but almost nothing related to logs.
I tried generating a pm2.launchBus but that only gets me current logs and not the old logs.

Answer 1

Usually for checking the pm2 logs:
run pm2 logs (process Id)
run pm2 show (process Id) and it would tell you the log location

Answer 2

May be not using PM2 API but a workable method would be read the logfile using fs and return to your client app

Answer 3

There isn't an API method to get the log data. You can only read it from disk. If you'd like to get more structured information about the log data you can configure the ecosystem (or process) JSON to either:
Add a timestamp
{
"apps" : [
{
"name": "app",
"script": "main.js",
"log_date_format": "YYYY-MM-DD hh:mm:ss"
}
]
}
Which results in:
2021-07-30 06:34:22: Hello World!
Write log entries as JSON
{
"apps" : [
{
"name": "app",
"script": "main.js",
"log_type": "json"
}
]
}
Which will get you:
{
"message": "Hello World!\n",
"timestamp": "2017-02-06T14:51:38.896Z",
"type": "out",
"process_id": 0,
"app_name": "app"
}
See Log Management docs