Custom Plug

[wet reef]

I have a route where I want to implement a plug that will check my auth before GraphQL processing. My problem is that the plug is not being called.

My pipeline looks like this:

pipeline :api do
    plug :accepts, ["json"]
    plug DxAppRcWeb.CheckAuth

    forward "/", Absinthe.Plug, schema: DxAppRcWeb.Schema
  end

The plug looks like this:

defmodule DxAppRcWeb.CheckAuth do
  import Plug.Conn

  alias DxAppRc.Auth.MockCheckAuth

  def init(_default), do: IO.puts("Auth Plug Init")

  def call(conn, opts), do: check_auth(conn, opts)

  def check_auth(conn, _opts) do
    IO.puts("Calling Check Auth...")
    auth_token = conn |> get_req_header("authorization")
    IO.inspect(auth_token, label: "Auth Token")
    validate_auth_token(conn, auth_token)
  end
  #... More business logic
end

There is no output indicating that the Plug has been initialized or is being called per call. Any thoughts/suggestions?

[torn orchid]

hi, just refer mix phx.gen.auth, it creates a module (UserAuth, same as your CheckAuth) then import to router.ex. Then adds a call func as a argument in a scope pipe_through:

    pipe_through [:browser, :redirect_if_user_is_authenticated]```
You can use `:api` instead of `:browser` .
:redirect_if_user_is_authenticated -> It is the function you need to call

[stiff knoll]

You shouldn't really depend on the time when init is called as it is configurable (it can be ran at runtime or at compile time, depending on the configuration)

[wet reef]

I have no dependencies on init - I'm literally just seeing if it's getting called, and trying to meet the min interface

The docs say I need to include init, so I'm including it.

[stiff knoll]

Yes, you need to have init/1 function

[wet reef]

I'll take a look at this, but it should be very simple to just create a plug from scratch...

[torn orchid]

yep, I know It will generate too many modules.
so, I suggest that you create a new phoenix project, then try it mix.gen.auth, then look at 2 modules UserAuth.ex and Router.ex. That's enough for Plug

[true breach]

that plug definitely looks like it should produce at least some output when being called, so maybe it's really not being called. Since you're using it inside a pipeline block, my best guess is that you're not actually hitting a route that uses that pipeline?