How to fix environment variables not working while running from system-d service in Go

You can follow along from here to make the use of the environment variables. The way I am using to implement environment variables in my project is GODOTENV go library. It is very easy to implement and platform independent.

Simply run

err = godotenv.Load(filepath.Join(path_dir, ".env"))

and you are done. Now you can use you code os.Getenv("APP_PATH") to read the keys from your .env file and it works perfectly fine with systemd service.

It depends on how you're running your systemd service. Systemd provide a bunch of derictive you should use:

[Unit]
Description=My service
After=network.target

[Service]
Type=simple
User=user
Group=user
EnvironmentFile=/home/user/env_file
ExecStart=/bin/bash -c -l '/home/user/go_program'
# ... other directive goes here

[Install]
WantedBy=multi-user.target

• EnvironmentFile - the file with ENV variables, that file will be loaded for you by systemd.

• User, Group - under which user and group the program should run.

• ExecStart=/bin/bash -c -l '/home/user/go_program' - the -l options makes bash act as if it had been invoked as a login shell, so the variable in your .bash_profile will be loaded(see User and Group section).

We have our environment variables in a .env file and use godotenv

    import {
       "github.com/joho/godotenv"
    }

    func main() {

        dir, err := filepath.Abs(filepath.Dir(os.Args[0]))
        if err != nil {
            log.Fatal(err)
        }
        environmentPath := filepath.Join(dir, ".env")
        err = godotenv.Load(environmentPath)
        fatal(err)
    }

and it works when we run our apps in daemon mode