VK Strategy for Überauth.

Setup

Create an VK application for you to use.

Register a new application at: VK devs and get the client_id and client_secret.

Include the provider in your configuration for Ueberauth

config :ueberauth, Ueberauth,
  providers: [
    vk: { Ueberauth.Strategy.VK, [] }
  ]

Then include the configuration for github.

config :ueberauth, Ueberauth.Strategy.VK.OAuth,
  client_id: System.get_env("VK_CLIENT_ID"),
  client_secret: System.get_env("VK_CLIENT_SECRET"),

If you haven’t already, create a pipeline and setup routes for your callback handler

pipeline :auth do
  Ueberauth.plug "/auth"
end
scope "/auth" do
  pipe_through [:browser, :auth]
  get "/:provider/callback", AuthController, :callback
end

Create an endpoint for the callback where you will handle the Ueberauth.Auth struct

defmodule MyApp.AuthController do
  use MyApp.Web, :controller

  def callback_phase(%{ assigns: %{ ueberauth_failure: fails } } = conn, _params) do
    # do things with the failure
  end
  def callback_phase(%{ assigns: %{ ueberauth_auth: auth } } = conn, params) do
    # do things with the auth
  end
end

You can edit the behaviour of the Strategy by including some options when you register your provider.

You can customize multiple fields, such as default_scope, default_display, default_state, profile_fields, uid_field

config :ueberauth, Ueberauth,
  providers: [
    vk: { Ueberauth.Strategy.VK, [
      default_scope: "email,friends,video,offline",
      default_display: "popup",
      default_state: "secret-state-value",
      uid_field: :email
    ] }
  ]

Default is empty (“”) which “Grants read-only access to public information (includes public user profile info, public repository info, and gists)”