How to read config variable in Phoenix / Elixir?

elixir phoenix-framework
Alex Craft picture Alex Craft · Mar 1, 2016 · Viewed 19.1k times · Source

I'd like to set the title of my app in my/config/config.exs file:

config :my, My.Endpoint,
  url: [host: "localhost"],
  root: Path.dirname(__DIR__),
  secret_key_base: "secret",
  title: "My App"

How can I read title later to use it in template? Something like:

<div>
  Title of my app is <%= ??? %>
</div>

I tried conn.title and it says there's no such key. But, when I try conn.secret_key_base it works. Why?

Answer

Tiago Engel picture Tiago Engel · Mar 2, 2016

The get_env function is part of the Application module from the Elixir/Erlang core.

This function returns the value for a specific key in the app's environment. Considering your configuration, you would access the title property this way:

Application.get_env(:my, My.Endpoint)[:title]

The third parameter is for passing a default value when the config key doesn't exist.

Related questions

How can I schedule code to run every few hours in Elixir or Phoenix framework?

So let's say I want to send a bunch of emails or recreate sitemap or whatever every 4 hours, how would I do that in Phoenix or just with Elixir?

Read More
How to Log something in Controller when Phoenix Server is running?

I'm trying to print some debug information from one of my Controllers in my Phoenix app when the server is running. defmodule PhoenixApp.TopicController do use PhoenixApp.Web, :controller def index(conn, _params) do log("this text") # ... end end

Read More
How to generate a random url safe string with Elixir

I need to be able to generate random url safe strings so I could use those in links (like in an activation link sent to a user's email), so how can I generate it? Is there a way to do …

Read More