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access_token(client_id, client_secret, redirect_uri, code)

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access_token(client_id(), client_secret(), String.t(), String.t()) :: resp()

Exchange an authorization code for an access token.

If you are implementing user authentication, the code is generated from a Facebook endpoint which is outside of the Graph API. Please see the Manually Build a Login Flow documentation for more details.


iex> Facebook.access_token("client_id", "client_secret", "redirect_uri", "code")
{:ok, %{
  "access_token" => access_token,
  "expires_in" => 5183976,
  "token_type" => "bearer"

See: https://developers.facebook.com/docs/facebook-login/manually-build-a-login-flow#confirm