Access token for server use.

[rinkusarumpllc]

the google sign in is working perfect in my Unity Iphone build however I want the access token as well so that I can send it over to the server and my server can check whether it is valid or not and fetch the detail from that access token.
All I have is the tokenID, AuthCode(Coming empty each time I'm sign in).
Is there a way to get the access token?

[PolestarWorkshop]

It's very easy to achieve.
Make POST (not GET) request from Unity to https://www.googleapis.com/oauth2/v4/token and pass these minimum set of parameters:
"client_id": Your Client ID (From Google API Credentials)
"client_secret": Your Secret (Also, from Google API credentials)
"grant_type", "authorization_code"
"code": Your authcode

grant_type, write exactly "authorization_code" if you want to get access token with your auth code.
If everything is correct, you receive something like:

{
  "access_token": "ya29.GlsVBofNLrM6iVT8B5BrSZAdx-sBvOkTbJpkljddEy__tgOdJJpZKppjq4oygggoXPTNfRxpEcBtLgptbCFEGUT0zf1z_oWYUPoGR8iJErmDwp7bkx5q8Ki4TA4f5P", 
  "token_type": "Bearer", 
  "expires_in": 3600, 
  "refresh_token": "1/LVAAPG2tlF5rl5aNUhu433Y7IT7Hen5ghsaA9tO9KBuP8"
}

[PolestarWorkshop]

If AuthCode is empty, add RequestAuthCode = true, in GoogleSignIn.Configuration instance init.

[rinkusarumpllc]

I've client_id from the firebase google configuration file but this client secret from where should i get this.
Are you talking about this : https://stackoverflow.com/questions/37418372/firebase-where-is-my-account-secret-in-the-new-console

[rinkusarumpllc]

This is what I'm getting.

[timnlupo]

Hi everyone, I'm calling the link like above but I am getting a malformed error. The call returns a 400 with the following
{ "error": "invalid_grant", "error_description": "Malformed auth code." }
Any ideas of what could be wrong?

[PolestarWorkshop]

This is what I'm getting.

I'm sorry for long delayed answer. You're making wrong request. I think you made request for auth code and access token from diffirient ip addresses. If you receive auth code from Unity, make request for access token from unity too.
Try this:

    IEnumerator GetAccessToken(string authcode)
    {
        WWWForm form = new WWWForm();
        form.AddField("client_id", "");
        form.AddField("client_secret", "");
        form.AddField("grant_type", "authorization_code");
        form.AddField("code", authcode);

        UnityWebRequest www = UnityWebRequest.Post("https://www.googleapis.com/oauth2/v4/token", form);
        yield return www.SendWebRequest();

        if (www.isNetworkError || www.isHttpError)
        {
            Debug.Log(www.error);
        }
        else
        {
			
			//Access token response
            Debug.Log(www.downloadHandler.text);

        }
    }

[FrankNine]

Thanks @PolestarWorkshop for sharing the solution.

I stumble upon some issues while implementing the solution and I would like to share here.
If you get 400 Generic Http Exception while posting to https://www.googleapis.com/oauth2/v4/token, make sure to check www.downloadHandler.text for detail error message from Google. I encountered two 400 errors.

The first one is malformated json, which is caused by this UnityWebRequest issue https://forum.unity.com/threads/unitywebrequest-post-url-jsondata-sending-broken-json.414708. There is a workaround in replies. I am using Unity 2017.4.23, not sure if later Unity fixes this or not. Maybe you can use BestHttp or cURL to avoid it all together.

The second 400 error is invalid_grant. I was only adding RequestAuthCode, after I added RequestEmail as well, the issue goes away.

[amaher-developer]

guys how i get code with out make login like in example
https://serving.photos.photobox.com/9186655920ac946b0e47102b0fae760342467b4b1efe4c5806bc6172fe8479cf6b930f17.jpg