bagex

Synopsis

bagex serves as an entrance for programs, it manages environment variables for the programs according to a configuration file.

Configuration

The configuration file is in toml format, and consists of 3 parts: path, env, and exe.

path: It is an array of paths, which will be prepended to the environment variable PATH when bagex tries to find a executable.
env: This section creates multiple one-to-many mappings from an environment variable to some executables.
exe: This section creates multiple one-to-many mappings from an executable to some environment variables.

An illustrative example configuration can be found here.

Usage

bagex takes an executable name as its argument, and tries to read its configuration from $XDG\_CONFIG\_HOME/bagex/config.toml if the environment variable XDG\_CONFIG\_HOME is set, otherwise it tries to read $HOME/.config/bagex/config.toml. Optionally use -c|--config-file to specify the configuration file to read. Example usage:

$ cat config.toml
[env.answer_to_the_ultimate_question_of_life_the_universe_and_everything]
42 = [
    "printenv",
]
[exe.printenv]
some_random_string = "YmFnZXgK"
pi = 3.14

$ bagex -c config.toml printenv
[..truncated..]
answer_to_the_ultimate_question_of_life_the_universe_and_everything=42
pi=3.14
some_random_string=YmFnZXgK

To add arguments for the requested executable (printenv in the above example), append the arguments after a double dash (--):

$ bagex -c ./config.toml bagex -- --version
bagex 0.1.0

Use -d|--dry-run to only shows the command to run and abort:

$ bagex -c ./config -d echo -- -en "Hello  world!"
/sbin/echo "-en" "Hello  world!"

Use cases

For systemd services

It is quite convenient to set a process' environment in a systemd service, but every time the environment has to change, one must run systemctl [--user] daemon-reload after changing the .service file, then call systemctl [--user] restart foo.service to update the running environment of the program.

bagex makes this process even more convenient by specifying the environment of a program in a separate config file, so that each time the environment is changed in bagex's config, only a systemctl [--user] restart foo.service has to be called.