Sticky variables

A little utility to keep environment variables around permanently* and share them between sessions. It does this by storing them in an sqlite database.

Should support any sufficiently POSIX-y shell, as well as Nushell.

Installation

From crates.io

At the time of writing, this crate hasn't been published to crates.io yet, but I assume this'll work in the future:

cargo install stickyvar

Hemorrhaging-edge releases

Go to the latest run of the build workflow and download the zip file for your platform:

• ubuntu-latest should work for Linux distros
• I'll let you figure out what windows-latest and macos-latest are for

Inside the zip file should be the executable (yes, that's the only thing inside the zip, blame GitHub for the unnecessary archiving).

Build it yourself

git clone git@github.com:ysthakur/stickyvar.git
cargo install --path stickyvar

Setup

POSIX-y shells

If you're using a sufficiently POSIX-y shell, such as Bash (get a better shell) or Zsh, then you can put the following into your .bashrc or .zshrc or whatever:

eval "$(stickyvar init sh)"

Nushell

If you're using Nushell, pat yourself on the back for your great taste in shells, then put the following in env.nu:

stickyvar init sh | save --force $"($nu.cache-dir)/stickyvar.nu"

It'll create a file stickyvar.nu every time you open Nushell. Alternatively, you can also manually generate the setup script just once if you prefer.

Then, put the following in config.nu to actually load the module from the setup script:

use $"($nu.cache-dir)/stickyvar.nu" sv

Usage

The init script generated earlier should've added an sv function/module with the following subcommands:

• sv set FOO BAR will set an environment variable FOO to BAR and add it to the sticky variable database
• sv load FOO will grab the value of FOO from the sticky variable database, then set the environment variable FOO to that in your current shell
• sv load (no extra arguments) will load and set all variables from the sticky variable database
• sv list will list names and values of sticky variables in the database
  • In Nushell, this actually just opens the database, so it also includes the last modified time of each variable (as seconds since Unix epoch)

Changing where variables are stored

You can set the environment variable STICKY_VAR_DB to control which file you want variables to be stored in. The file doesn't need to exist, but the directory it's in does. You can then check that stickyvar is using the correct path using stickyvar db-path.

Here's an example:

 stickyvar db-path
/home/ysthakur/.local/state/stickyvar/sticky-var.db
 $env.STICKY_VAR_DB = "foo.db"
 stickyvar db-path
foo.db

Sharing variables between two sessions

Suppose you have two sessions that you want to share environment variables between, but you don't want any other sessions to get the same variables. You can handle this by having both sessions use the same database file, different from the default one.

If you set the environment variable STICKY_VAR_DB to, say, ~/foo.db in both sessions, they'll both use variables from there, but other sessions will continue using the default database.

TODO asciinema recording

TODOs:

• Pre-prompt hooks for Zsh and Nushell to update variables?
  • Not sure how much time it would take to load all sticky variables every prompt
  • Need to determine which variables to update? Possibly complicated
• Install shell hook to run every time any environment variable is set
  • Record the last time an environment variable was set in a session-specific database
  • Why? sync subcommand that reads all sticky vars and only updates env vars that are newer than the found sticky vars
  • Not sure how useful this would be
• Set normal shell variables in Nushell rather than just environment variables. Typing $env.foo is annoying, $foo is easier