Looking for better way to run elixir code

Question

New to elixir and I only have found 2 ways to run code. Wondering if there's a better way:

1. open interactive shell and run one or multiple functions inside a module by calling Module_name.function_name() which just runs that function

2. If I want to run the entire module then I open interactive shell and have to paste all the code from the module into the shell then hit enter

I'm sure it's obvious but I can't find any satisfactory answers anywhere. Just tried option #2 with this module and it returned this when it should return a list of reviews. Thanks.

defmodule KgbScrape do
  use HTTPoison.Base
  @endpoint "https://www.dealerrater.com/dealer/McKaig-Chevrolet-Buick-A-Dealer-For-The-People-dealer-reviews-23685/page"

  def build_urls() do
    page_num = ["1","2","3","4","5"]
    tail_url = ["/?filter=#link"]
    for page <- page_num, tail <- tail_url do
      urls_list = @endpoint <> page <> tail
    end
  end
  def fetch_pages(url) do
    url
    |> HTTPoison.get()
    |> response()
  end

  def process_pages(urls_list) when is_list(urls_list) do
    resp =
      urls_list
      |> Task.async_stream(fn url -> fetch_pages(url) end)
      |> Enum.map(fn {_, resp} -> resp end)

    Enum.map(resp, fn r ->
      r
      |> Floki.parse_document!()
      |> Floki.find(".review-entry")
      |> Map.new(fn entry ->
        [{"div", _, [date]}] = Floki.find(entry, "div.italic")
        [{"p", _, [content]}]  = Floki.find(entry, "p.review-content")
        {date, content}
      end)
    end)
  end

  def response({:ok, %{body: {:ok, %{"error" => error}}}}) do
    {:error, error}
  end
  def response({:ok, %{body: body}}), do: body
  def response({:error, error}), do: {:error, error}
end

and result is:

warning: redefining module KgbScrape (current version loaded from _build/dev/lib/kgbScrapeApp/ebin/Elixir.KgbScrape.beam)
  iex:7

warning: variable "urls_list" is unused (if the variable is not meant to be used, prefix it with an underscore)
  iex:15: KgbScrape.build_urls/0

{:module, KgbScrape,
 <<70, 79, 82, 49, 0, 0, 68, 252, 66, 69, 65, 77, 65, 116, 85, 56, 0, 0,
   5, 107, 0, 0, 0, 103, 16, 69, 108, 105, 120, 105, 114, 46, 75, 103,
   98, 83, 99, 114, 97, 112, 101, 8, 95, 95, 105, 110, 102, ...>>,
 {:response, 1}}

Answer 1

Create a mix project and use iex -S mix as described in the documentation to load all the modules in the project.

The outcome you see is the result of module compilation. To use the module one must explicitly call a function, like KgbScrape.process_pages(["url1", "url2, ...]).

Also, one might create an escript with mix escript.build and run the resulting executable.

Answer 2

I've never used Elixir, but according to the getting started documentation, you can use the elixir command:

After getting familiar with the basics of the language you may want to try writing simple programs. This can be accomplished by putting the following Elixir code into a file:

IO.puts("Hello world from Elixir")

Save it as simple.exs and execute it with elixir:

$ elixir simple.exs
Hello world from Elixir