use_env_dir

use_env_dir is a function for direnv.

It loads environment variables one par file under the .direnv/env directory.

This functionality is very similar to which is seen in Heroku Buildpack.

Each file under the "env_dir" represents an environment variable, whose filename to be the variable's name and content to variable's value.

So the file with the name DB_PORT and the content 32800 will turn to an environment variable of DB_PORT=32800.

How to use

Add the following line to your ~/.config/direnv/direnvrc:

source_url "https://raw.githubusercontent.com/kayhide/direnv-use-env-dir/master/use_env_dir.sh" "sha256-OhI9bdI6Wk+/lVcAgxF2ePH5s4znGIGorIKw6qREDBk="

Then in any .envrc, put the following line:

use_env_dir

You can also specify the env dir as:

use_env_dir /path/to/your/env/dir

Use case

One use case of this functionality is to launch a database server container by docker-compose and let it to pick any available port. You can fill DB_PORT by creating a corresponding file as:

$ mkdir -p .direnv/envs
$ docker-compose port db 5432 | cut -d ':' -f 2 > .direnv/envs/DB_PORT

And make your application to read the DB_PORT.

In this way, you can access the db without worrying about port conflict, no matter how many similar projects you are working on in parallel.