How to escape multiline values in .env file

[justintemps]

First of all, thanks a million for this action, it's super useful.

I was wondering how to escape multiline env vars. let's say I have a cert that I want to pass to my .env file from a github secret. This works locally because I can wrap the cert in quotes in my local .env file. How can I accomplish the same thing with this action? I don't think it does this by default, because right now I'm getting the following error when I try to run docker-compose

Run docker compose -f docker-compose.yml -f production.yml build
unexpected character "+" in variable name near "***\n***\n***\n***\n***\n***\n***\n***\n***\n***\n***\n***\n***\n***\n***\n***\n***\n***\n***\nPOSTGRES_DB=***\nPOSTGRES_HOST=***\nPOSTGRES_PASSWORD=***\nPOSTGRES_PORT=***\nPOSTGRES_USER=***\nREDIS_HOST=***\nREDIS_PASSWORD=***\nREDIS_PORT=***\n"
Error: Process completed with exit code 1.

[justintemps]

It seems like something like this should work but it doesn't.

envkey_MULTILINE_ENV_VAR: "${{ secrets.MULTILINE_ENV_VAR }}"

[justintemps]

I eventually got this to work by base64 encoding the multiline env var so that it wouldn't be multiline anymore, and then decoding it in the application where I needed to use it. But it seems like may be this is a scenario the lib should handle?

[AngelOnFira]

Hmm, I haven't thought about this use case before, but I suppose it isn't too hard to put something with multiple lines in a Github Secret. However, I'm wondering what the semantics of an environment file tend to be, I imagine most parsers would expect one variable per line?

This seems like it would be best as an opt in feature. Like if you accidentally pass a multi-line variable, then I imagine it would normally be better to error than allow it. Something like:

api_key=fgs87ssfg9897sdf
longer_key=adsfhalkjdhfkljash
fadsfjfadshfalkj
something_else=True

Would be an error if parsed I'd assume. Can you give an example of how you'd expect some multiline variables to look?

[justintemps]

I'm specifically thinking of an RSA key or some similar value where the line breaks are meaningful and have to be encoded in some way.

In my instance, I was using dotenv in a Node.js project which supports wrapping multiline variables in quotes like this.

PRIVATE_KEY="-----BEGIN RSA PRIVATE KEY-----
...
HkVN9...
...
-----END DSA PRIVATE KEY-----"

I guess in this situation, create-envfile needs to know if you're intentionally passing in a variable that has linebreaks or if you're not and it should through an error.

This seems a little hacky, but may be just adding something to the prefix like:

envkey_multiline_SECRET_KEY

[AngelOnFira]

Would an alternative solution be to format any incoming secrets that are multiline to instead just include newline characters \n at any newline?

From that dotenv readme:

---

---

This would be easier to implement, and shouldn't break anything I think. Or rather, are there cases where this wouldn't work?

[justintemps]

Yea @AngelOnFira that would be awesome.