Database credentials for dev config?

[thojanssens]

Hello, I am a beginner in Elixir/Phoenix and I am having a look at your project for learning purposes.

I want to create/migrate the database but I have an error:
$ mix ecto.create

** (RuntimeError) connect raised KeyError exception: key :username not found.

One can quickly see that there are missing parameters specifying username/password:
https://github.com/thoughtbot/constable/blob/master/config/dev.exs#L41

How does it work? Where does it get the credentials from? I guess I'm not supposed to add options myself by editing the code?

Thank you for any help!

[thojanssens]

Alright the postgrex library will find some predefined env variables:
Keyword.put_new(:username, System.get_env("PGUSER") || System.get_env("USER"))

Maybe gotta mention that in the installation guide.