Configuration in runtime about cors_plug HOT 9 CLOSED

Of course, you can recompile. My point is changing the configuration of the app using environment variables or another kind of runtime configuration. So, I compile once my project but I execute it in different environments, production and staging. The binary is exactly the same, the configuration is different. I'd like to change the CORS origin depending on the environment.

I don't know how to do this in your library. Maybe you get some ideas from Michal Muskala's post: http://michal.muskala.eu/2017/07/30/configuring-elixir-libraries.html#recommendations-for-library-authors

Thank you for your time

from cors_plug.

Right, it sounds like functions would be the best way to go for you @alexcastano, can you confirm?

from cors_plug.

Hey @alexcastano can you provide an example please? You should be able to use environment variables as long as you recompile (which might be the culprit here).

See also http://blog.plataformatec.com.br/2016/05/how-to-config-environment-variables-with-elixir-and-exrm/

from cors_plug.

If you find a solution you like, I can submit a pull request to implement it :)

from cors_plug.

You can just use function config for your issue, for instance:

defmodule Api
  def origins do
    ~r/http:\/\/localhost:\d{1,4}$|#{Application.get_env(:api, :allowed_origins)}/
  end
end

plug CORSPlug, origin: &Api.origins/0

This way the function Application.get_env will be called in runtime each time, not during compilation, so your settings will be loaded properly.

I assumed you use erlang release variables like:

config :api, allowed_origins: "${ALLOWED_ORIGINS}"

from cors_plug.

I tried this but I didn't work for me. This is the error I have in the logs:

{"could not start kernel pid",application_controller,"error in config file \"/opt/app/var/sys.config\" (119): syntax error before: Fun"}

In that line I have:

{cors_plug,
     [{origin,#Fun<Elixir.Api.Cors.origins.0>},

I use distillery and docker to deploy. I found this issue in bitwalker/exrm#230. It seems not possible to add a function in config.

Any suggestion?

from cors_plug.

I believe your issue is a dupe of #46. Try a named function whose reference you pass instead of (what I assume is) an anonymous function.

from cors_plug.

Hi @mschae, it was not an anonymous function, but I was using config.exs and Mix.Config does not support function arguments. Using just the keyword, without Mix.Configas the argument for the plug works.

Thank you for your time.

from cors_plug.

Thanks for this thread, pointed me in the right direction. Indeed, defining origins using an anonymous function resolved the issue of not being able to correctly set the origins when dependent on runtime.exs -

# runtime.exs
import Config

if config_env() == :prod do
  config :my_app,
    allowed_origins: String.split(System.get_env("ALLOWED_ORIGINS") || "*", " ", trim: true)
end

# endpoint.ex
defmodule MyApp.Endpoint do
  plug CORSPlug, origin: &__MODULE__.allowed_origins/0

  def allowed_origins(), do: Application.get_env(:my_app, :allowed_origins)
end

from cors_plug.