Where should the .env file be placed?

[SquireOfSoftware]

I feel like this is a fairly obvious question but I am also fairly certain that my rust/crate naivety is also at play here.

Where should the .env file be placed?

I have a project that I have been tinkering away with and I have it set up like so:

/
/.env <-- has the env var `DB_USER=test`
/graphql_api
/graphql_api/.env <-- has the env var `DB_USER=api`
/front_end
/front_end/.env <-- does NOT have the env var `DB_USER`

And I noticed that if I run: cargo run -p graphql_api from the root directory it will get the env var of DB_USER=test from the root directory, but if I run cargo run -p graphql_api from the graphql_api directory then it will pick up DB_USER=api.

So I have two general questions:

1. Is it expect that the .env file is based on the location of where you run your cargo command?
2. Is it best practice to have workspaces that have their own .env files?
3. Is there a way for me to point dotenv under the workspace to use the "workspaces" own .env file? Or is the expectation that you run your cargo command when you are in the right location and therefore this question is just plain moot?

Feel free to let me know if these questions are also invalid because I have just come off the Rust book fairly recently and was curious about the actual behaviour of dotenv...but recently discovered that it was unmaintained and the torch has been sorta passed to this repo?

And also feel free to point me to documentation to read since it seems my googlefu is failing me on these questions.

[allan2]

Hi @SquireOfSoftware,

Docs are on docs.rs. When a crate is published to crates.io, the docs are automatically generated.

1. You can put the .env file(s) wherever you want. dotenv() picks up the first file named .env, looking in the current directory and then upward in the parent directories.
2. I'm not sure if I would call it a best practice, but I like to have a single .env file at the project root for simplicity.
   If you are mimicking a production setup and would like to keep separate sets of environment variables, you could do:

dotenvy::from_path("/path/to/project/.env.backend")?;
dotenvy::from_path("/path/to/project/.env.frontend")?;

3. There is from_path and from_filename. from_filename picks up the first matching filename, which may be handy if you are running cargo from different places and want to use relative paths to your .env files.

Hope this helps! Let me know if you have any other questions.

[SquireOfSoftware]

Ah cool, thanks for all the answers and the link to the docs.rs site!