Can't access environment variables in leiningen project.clj with environ

Question

I am trying to use environ to access environment variables specified in my project.clj :dev profile. This looks like a nice way to set up different configuration options, but I can't seem to get it to work. My project.clj entry looks like this:

:profiles
{:dev {:dependencies [[javax.servlet/servlet-api "2.5"]
                      [ring-mock "0.1.5"]]
       :env {:foo "FOO" :bar "BAR"}}}

If I run lein repl and require then enter (with in-ns) a namespace from my project, environ.core/env just returns nil:

(environ.core/env :foo)
nil

Adding an :env entry to the :user profile in .lein/profiles.clj also doesn't work. What am I doing wrong?

Micropaleontology

If you run (System/getenv) do you see "FOO", or maybe "foo" or ":foo" as any of the keys? I notice that (env.core/env :pwd) returns the value referenced by the "PWD" key in my environment for example. – Kathleenkathlene

@Kathleenkathlene Well I can pick up environment variables like PATH with environ, it's just the ones defined under my defproject :profiles that it doesn't seem to see. No, I don't see any variation on foo. – Micropaleontology

If environ can get other env vars, this is not an environ problem, it is a leiningen one. Most likely you aren't adding the env vars correctly. – Kathleenkathlene

@Kathleenkathlene That's just what I thought, but I'm pretty sure I am. Compare to the accepted answer here. – Micropaleontology

Answer 1

OK, it was a case of reading the docs more thoroughly. :) To access environment variables specified in the project map you need the lein-environ plugin. Add it like this:

:plugins [[lein-environ "0.4.0"]]

That worked. It's easy to miss that in the docs though.

Micropaleontology