[updatenotification] Fix pm2 using detection when pm2 script is inside or outside MagicMirror root folder

[bugsounet]

This will fix #3576

@FrankBlackMG:

I don't use *env.unique_id because some others modules can use pm2 too for starting a service and unique_id is the same (this will make confusion)
So I check name and pm_id for found it

[FrankBlackMG]

@bugsounet , I think what you have is fine too. But I will say that unique_id is in fact unique and can't be confused with any other process. There will be no other pm2 processes using this. It's a GUID/UUID.

https://github.com/Unitech/pm2/blob/5e20239d63c0664cadda12c52f60e03caaf8cc14/lib/God.js#L102

[bugsounet]

Not sure, just check this:

<...>
list.forEach((pm) => {
  Log.debug(`[PM2] pm2 name: ${pm.name} -- in process env: ${process.env.name} unique_id: ${process.env.unique_id}`)
  Log.debug(`[PM2] pm2 pm_id: ${pm.pm_id} -- in process env: ${process.env.pm_id}`)
  if (pm.pm2_env.status === "online" && process.env.name === pm.name && +process.env.pm_id === +pm.pm_id) {
    this.PM2 = pm.name;
    this.usePM2 = true;
    Log.info("updatenotification: [PM2] You are using pm2 with", this.PM2);
    resolve(true);
  }
});
<...>

Result:

[DEBUG] [PM2] pm2 name: VLCServer -- in process env: MagicMirror unique_id: 6081a1d6-1ada-4dc9-81e5-91ee79ad2906 
[DEBUG] [PM2] pm2 pm_id: 0 -- in process env: 2 
[DEBUG] [PM2] pm2 name: librespot -- in process env: MagicMirror unique_id: 6081a1d6-1ada-4dc9-81e5-91ee79ad2906 
[DEBUG] [PM2] pm2 pm_id: 1 -- in process env: 2 
[DEBUG] [PM2] pm2 name: MagicMirror -- in process env: MagicMirror unique_id: 6081a1d6-1ada-4dc9-81e5-91ee79ad2906 
[DEBUG] [PM2] pm2 pm_id: 2 -- in process env: 2
[INFO]  updatenotification: [PM2] You are using pm2 with MagicMirror 

That you can see unique_id is the same on all pm2 process

[FrankBlackMG]

What you're logging is the MagicMirror process's unique id (this process) i.e. what you need to compare with. That won't change. Try logging the value which is for each of the PM2 managed process.

pm.pm2_env.unique_id

I did this and got different values for each pm2 managed process. One of which was the MagicMirror process and it match the

process.env.unique_id

In my logging I saw unique ids that are different for each pm2 managed process list, one of which matched this process's unique id.

[sdetweil]

i do this in my MMM-Config

pm2 jlist
then loop thru the apps

if(__dirname.startsWith(managed_process.pm2_env.pm_cwd)

this has issues if multiple instances are running from the same MagicMirror folder. but this is an odd env

[FrankBlackMG]

using unique id covers that case. It doesn't matter where or how PM2 is used to manage MagicMirror or any other process.

if (process.env.unique_id !== undefined && process.env.unique_id === pm.pm2_env.unique_id) {

[bugsounet]

That will not work process.env.unique_id will be equal to pm.pm2_env.unique_id:

[DEBUG] [PM2] pm2 name: VLCServer -- in process env: MagicMirror unique_id: 8ef0320a-da01-4155-87ba-d26b04d4aaac --> pm2_env.unique_id: 8ef0320a-da01-4155-87ba-d26b04d4aaac 

[DEBUG] [PM2] pm2 name: librespot -- in process env: MagicMirror unique_id: 8ef0320a-da01-4155-87ba-d26b04d4aaac --> pm2_env.unique_id: 8ef0320a-da01-4155-87ba-d26b04d4aaac 

[DEBUG] [PM2] pm2 name: MagicMirror -- in process env: MagicMirror unique_id: 8ef0320a-da01-4155-87ba-d26b04d4aaac --> pm2_env.unique_id: 8ef0320a-da01-4155-87ba-d26b04d4aaac

[INFO]  updatenotification: [PM2] You are using pm2 with MagicMirror

Test with your solution:

[DEBUG] [PM2] pm2 name: VLCServer -- in process env: MagicMirror unique_id: 8ef0320a-da01-4155-87ba-d26b04d4aaac --> pm2_env.unique_id: 8ef0320a-da01-4155-87ba-d26b04d4aaac 
[INFO]  updatenotification: [PM2] You are using pm2 with VLCServer 

[DEBUG] [PM2] pm2 name: librespot -- in process env: MagicMirror unique_id: 8ef0320a-da01-4155-87ba-d26b04d4aaac --> pm2_env.unique_id: 8ef0320a-da01-4155-87ba-d26b04d4aaac 
[INFO]  updatenotification: [PM2] You are using pm2 with librespot 

[DEBUG] [PM2] pm2 name: MagicMirror -- in process env: MagicMirror unique_id: 8ef0320a-da01-4155-87ba-d26b04d4aaac --> pm2_env.unique_id: 8ef0320a-da01-4155-87ba-d26b04d4aaac 
[INFO]  updatenotification: [PM2] You are using pm2 with MagicMirror

[sdetweil]

hm, just worked for me

the process.env.unique_id is added by pm2 when the app is launched
and the pm2 info will only match 1

i have 8 processes defined under pm2 only 1 matches
parsed content from pm2 jlist

output.forEach((managed_process) => {
                  if(managed_process.pm2_env.status === 'online' ){
                    if(process.env.unique_id === managed_process.pm2_env.env.unique_id){
                     ...
                    }
                  }
})

i don't break, and only find one matching when others are running

[bugsounet]

yes but the other processes are not launched by MM itself

I say:

I don't use *env.unique_id because some others modules can use pm2 too for starting a service and unique_id is the same (this will make confusion)

[sdetweil]

yes but the other processes are not launched by MM itself

i don't understand this..

if they are launched by pm2, then they are launched by pm2. (thru exec or outside MM)
if they are launched by MM, thru exec, then they are NOT launched by pm2

we only care in MM is launched by pm2.. pm2 apps run independent of the launcher
if an MM module uses pm2(exec...) to launch sub'tasks', then its the modules job to find them again if MM is restarted

[bugsounet]

don't forget that all exec are executed inside MM process (like a sub process)

[bugsounet]

[DEBUG] [PM2] pm2 name: VLCServer -- in process env: MagicMirror unique_id: 8ef0320a-da01-4155-87ba-d26b04d4aaac --> pm2_env.unique_id: 8ef0320a-da01-4155-87ba-d26b04d4aaac 
[INFO]  updatenotification: [PM2] You are using pm2 with VLCServer

So explain me why we are able to detect an MagicMirror pm2 using with this process ?
(by using: if (process.env.unique_id !== undefined && process.env.unique_id === pm.pm2_env.unique_id) {

---> So the result will be : "ok i found MagicMirror with VLCServer process and i will use it for restart MagicMirror"

That why if (pm.pm2_env.status === "online" && process.env.name === pm.name && +process.env.pm_id === +pm.pm_id) { is better

[sdetweil]

I have multiple apps called MagicMirror, but with different IDs'
I don't know what 'vlcserver' means above..

MM is an app.. it has a process env, seen by the node_helpers and base process (before electron createWindow)
when pm2 starts a registered app, it adds that apps unqiue_id to the the process environment

now you can match the process env value with the pm2 app list value by app..
if those match, then you know the pm2 app info to start/stop/restart... as compared to any other app.
if there is no pm2_unique_id, then it was NOT started with pm2. (and can't be restarted w pm2)
I don't see any app identifier in your code.. is this because of the pm2 library?
I use the pm2 command process jlist to get the json for all the apps.

[sdetweil]

my code to detect the id in pm2 for this running MM, using the ID now

        // if the id was not set from config
        if(pm2_id  ==  -1){
          // if the pm2 process_env is set
          if(process.env.unique_id !== undefined){
            // running under pm2
            if (debug) console.log("getting pm2 process list");
            exec("pm2 jlist", (error, stdout, stderr) => {
              if (!error) {
                let o=stdout.toString()
                // maybe there is a pm2 error message in front of the json
                if(!o.startsWith('[')){
                  // remove everything before process list
                  o=o.slice(o.indexOf('['))
                }
                if(debug){
                  console.log("json="+o)
                }
                let output = JSON.parse(o);
                if (debug)
                  console.log(
                    "processing pm2 jlist output, " + output.length + " entries"
                  );
                output.forEach((managed_process) => {
                  if(managed_process.pm2_env.status === 'online' ){
                    if(process.env.unique_id === managed_process.pm2_env.env.unique_id){
                      if (debug)
                        console.info(
                          "found our pm2 entry, id=" + managed_process.pm_id
                        );
                      pm2_id = managed_process.pm_id;
                    }
                  }
                });
              }
            });
          } else {
            if(debug)
              console.info(this.name+" MagicMirror not running under pm2")
          }
        }
        else {
          if(debug){
            console.info(this.name+" pm2 restart app id is ", pm2_id)
          }
        }

[bugsounet]

Your part of the code requires a lot of effort but don't works :/

[LOG]   processing pm2 jlist output, 3 entries 
[LOG]   managed_process.pm_id: 0 managed_process.pm2_env.env.unique_id: fb62b1cf-a0ef-4e52-8031-e216a788f39f 
[INFO]  found our pm2 entry, id=0 
[LOG]   managed_process.pm_id: 1 managed_process.pm2_env.env.unique_id: fb62b1cf-a0ef-4e52-8031-e216a788f39f 
[INFO]  found our pm2 entry, id=1 
[LOG]   managed_process.pm_id: 2 managed_process.pm2_env.env.unique_id: fb62b1cf-a0ef-4e52-8031-e216a788f39f 
[INFO]  found our pm2 entry, id=2

I will purpose a new code with process.pm2_env.env.unique_id checking

[sdetweil]

ok, i don't see that problem in my module, only one pm2 app matches the environment variable