Testing a controller that makes outside api calls

Questions & Help Questions
, ,
9

I like this idea of configuration through config.exs and test.exs.

Revising the example

Based on your feedback, the new set up for the controller would use the @endpoint attribute and it would return a url based on the environment that it’s in.

controller(revised)

defmodule MyAppWeb.Api.TweetController do
  use MyAppWeb, :controller
  action_fallback MyAppWeb.Api.FallbackController

  @endpoint Application.get_env(:myapp, :url)

  def index(conn, params) do
    with {:ok, result} <- TwitterClient(@endpoint).post_tweet("Elixir is awesome!") do
      render(conn, "show.json",  tweet: result)
    end
  end
end

How do I test this controller in my test controller?

test controller

defmodule MyAppWeb.Api.TweetControllerTest do
  use MyAppWeb.ConnCase

# I just need to put this here and it will work??
 setup do
    bypass = Bypass.open()
    {:ok, bypass: bypass}
  end

  describe "GET /tweet" do
    test "success, it sends a tweet", %{conn: conn, bypass: bypass} do
      # Is `bypass` being passed here the same bypass
     # that is in my config :myapp, TwitterClient, url: BYPASS_ENDPOINT
       Bypass.expect(bypass, fn conn ->
            conn
            |> Plug.Conn.put_resp_header("content-type", "application/json")
            |> Plug.Conn.resp(200, %{tweet: "Elixir is awesome"})
      end)
      # controller
      conn = get(conn, "/tweet")
      assert json_response(conn, 200) == %{tweet: "Elixir is awesome"}
    end
  end
  
end