[Solved] Shell service is immediately inactive after systemctl startup

[fisticuff]

Heyo, new mint user here. Having an issue with `systemctl` not keeping a simple shell script service alive persistently. The script itself runs as expected when ran manually via the terminal; the systemctl service activated one does not. Curious on if I can get a hand on what the solution could be.

OS:
Linux Mint 20.3 Cinnamon

Shell Script:
Simple script that watches dbus for system "lock" and "unlock" signals.

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#! /bin/bash

dbus-monitor --session "type='signal',interface='org.cinnamon.ScreenSaver'" |
    while read x; do
        case "$x" in
            *"boolean true"*) 
                "/home/<user>/scripts/systemLockUnlock/systemOnLock.sh";;
            *"boolean false"*)
                "/home/<user>/scripts/systemLockUnlock/systemOnUnlock.sh";;
        esac
    done

Service File (/etc/systemd/system/lockUnlock.service):

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[Unit]
Description=Toggle LED's based when the cinnamon screen saver sends out a locked/unlocked signal.

[Service]
Type=simple
ExecStart=/home/<user>/scripts/systemLockUnlock/lockUnlock.sh

[Install]
WantedBy=default.target

This command produces the following logs:

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sudo systemctl daemon-reload; sudo systemctl enable lockUnlock.service; sudo systemctl start lockUnlock.service; sudo systemctl status lockUnlock.service

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Created symlink /etc/systemd/system/default.target.wants/lockUnlock.service → /etc/systemd/system/lockUnlock.service.
● lockUnlock.service - Toggle LED's based on if the system is locked or not.
     Loaded: loaded (/etc/systemd/system/lockUnlock.service; enabled; vendor preset: enabled)
     Active: inactive (dead) since Sat 2022-07-02 12:22:12 CDT; 6ms ago
    Process: 9143 ExecStart=/home/<user>/scripts/systemLockUnlock/lockUnlock.sh (code=exited, status=0/SUCCESS)
   Main PID: 9143 (code=exited, status=0/SUCCESS)

Jul 02 12:22:12 <system> systemd[1]: Started Toggle LED's based on if the system is locked or not..
Jul 02 12:22:12 <system> lockUnlock.sh[9145]: Failed to open connection to session bus: Unable to autolaunch a dbus-daemon without a $DISPLA>
Jul 02 12:22:12 <system> systemd[1]: lockUnlock.service: Succeeded.

* Ignore the different description messages in the logs and the service file. Created and deleted few of these trying to figure out what the problem could be
* Note that user and system names have been replaced with <user> and <system>

[fisticuff]

Figured it out thanks to a somewhat related github post https://github.com/openrazer/openrazer/issues/639 based on the error message:
"Failed to open connection to session bus: Unable to autolaunch a dbus-daemon without a $DISPLAY for X11".

Just had to change the daemon from being system based to user based. I guess the `dbus-monitor` is user based? Not sure still. The "lock" and "unlock" scripts needed use of a few user based daemons anyway.

Here's the steps I took:
1. Move the `.service` file to the user folder:

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sudo mv /etc/systemd/user/lockUnlock.service ~/.config/systemd/user/

2. Do the usual `systemctl` commands but with the `--user` flag and no `sudo` as its user based:

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systemctl --user daemon-reload; systemctl --user enable lockUnlock.service; systemctl --user start lockUnlock.service

Would still prefer this particular daemon to run on system boot rather than user login, but that would be for a different post.