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Ueberauth OAuth2 Authentication for Elixir project with LINE Messenger

Hello Elixir fellows!
Released yesterday first version of the ueberauth_line package for oauth authetication for your elixir project.
Installation and using is pretty straightforward, you can use any of other Ueberauth tutorials, like Ueberauth for Facebook.

Tricky thing in using LINE OAuth is setting up LINE Channel and handling errors because they are now really readable (they put error codes in the URL, so keep an eye on your browser address bar).
Be sure you went every step described here in the LINE web login settings very carefully.

Please note that LINE doesn’t provide user email address so we need to mimic it with the LINE user ID and if you need an email for user you’ll need to implement additional step of adding an email.

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Add Facebook Open Graph tags to Phoenix Framework web page

Hi there,

This is very easy:

1. Create a function in LayoutView `web/views/layout_view.ex`:

    def ogtags(assigns) do
        if assigns[:ogtags] do
          for {key, value} <- assigns[:ogtags] do
              raw("\t\n")
          end
        else
          raw("\t\n")
        end
    end

Here I was using `content_tag` function but it created closed `</meta>` tag which I don’t really like.
In the else clause you can put some default OG tags, I put only `fb:app_id` fir the start.

2. Add this function to the app layout template `web/templates/layout/app.html.eex`:

<%= ogtags(assigns) %>

Where `assigns` is the map which contains almost everything you need to render the view.

3. Update your controller function with OG tags tuple and pass it to template like this:

  def show(conn, %{"token" => token}) do
    dream = Repo.get_by!(Dream, token: token)
    dream = Repo.preload dream, :user

    ogtags = %{
        "fb:app_id": "430839153628230",
        "og:type": "article",
        "og:site_name": "InstaDreams",
        "og:title": dream.title,
        "og:description": dream.body || dream.title,
        "og:audio": InstadreamsPhoenix.Router.Helpers.url(conn) <> "/uploads/dreams/#{dream.user.user_id}/#{dream.audio_filename}.mp3",
    }

    render(conn, "show.html", dream: dream, ogtags: ogtags)
  end

I guess the code here is self-explanatory (I used code from my pet-project www.instadreams.com).
If you have some thought how we can improve the code above feel free to post a comment here 🙂