Trying to verify google idToken using Joken & JokenJwks

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1

Hi
I am trying to verify and validate idToken jwt from google oauth to sign in and create a user.
I am using Joken and JokenJwks

my_strategy.ex

  defmodule MyApp.MyStrategy do
    use JokenJwks.DefaultStrategyTemplate
  
    def init_opts(opts) do
      url = "https://www.googleapis.com/oauth2/v3/certs"                                                                                  
      Keyword.merge(opts, jwks_url: url)
    end
end

google_token.ex

defmodule MyApp.GoogleToken do
     use Joken.Config
     
     add_hook(JokenJwks, strategy: MyApp.MyStrategy)
     
     #@impl true
     def token_config do
       # validate from the token
       default_claims()                                                                                                                    
      |> add_claim("iss", nil, &(&1 == "https://accounts.google.com"))
      |> add_claim("aud", nil, &(&1 == "client_app_id"))
    end
  end

application.ex

def start(_type, _args) do
       # List all child processes to be supervised
      children = [
       # other code,,,,
        {MyApp.MyStrategy, time_interval: 60_000},                                                                                        
      ]
  # other code..
   
end

in iex session

token = "idToken"
token_config = GoogleToken.token_config()

then I called

GoogleToken.verify_and_validate(token_configs, token)

and got an error

(FunctionClauseError) no function clause matching in Joken.verify/3 
Attempted function clauses (showing 3 out of 3):
    
        def verify(bearer_token, nil, hooks) when is_binary(bearer_token) and is_list(hooks)
        def verify(bearer_token, signer, hooks) when is_binary(bearer_token) and is_atom(signer)
        def verify(bearer_token, signer = %Joken.Signer{}, hooks) when is_binary(bearer_token)
    
    (joken) lib/joken.ex:242: Joken.verify/3
    (joken) lib/joken.ex:296: Joken.verify_and_validate/5

What am I missing?

2

Hey, let’s see if I can help.

You don’t need to pass the configuration for verify_and_validate of your module. All you need is

GoogleToken.verify_and_validate(token).

You pass the config as a first parameter when you use Joken.verify_and_validate directly.

Hope it helps.

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