get Firebase Access token (oAuth2)

[waleedmakarem]

Can i use the library to get Firebase Access token (oAuth2) . I have firebase ServiceAccount json data. below is my running java code that works using

private static final String firebaseMessagingScope = "https://www.googleapis.com/auth/firebase.messaging";

public void getAccessTokenfromFile(Context mcontext, AccessTokenCallback callback) {
    new Thread(new Runnable() {
        @Override
        public void run() {
            try {
                InputStream stream = mcontext.getAssets().open("serviceaccount.json");
                GoogleCredentials googleCredentials = GoogleCredentials.fromStream(stream).createScoped(firebaseMessagingScope);
                googleCredentials.refresh();
                final String token = googleCredentials.getAccessToken().getTokenValue();
                // Handle the token here
                callback.onAccessTokenReceived();
            } catch (Exception e) {
                callback.onAccessTokenError(e.getMessage());
            }
        }
    }).start();

}

my service account file as below data headers:

<title></title> <style type="text/css"> p.p1 {margin: 0.0px 0.0px 0.0px 0.0px; font: 13.0px '.AppleSystemUIFont'} table.t1 {border-collapse: collapse} td.td1 {border-style: solid; border-width: 1.0px 1.0px 1.0px 1.0px; border-color: #9a9a9a #9a9a9a #9a9a9a #9a9a9a; padding: 1.0px 5.0px 1.0px 5.0px} </style>

type

project_id
private_key_id
private_key
client_email
client_id
auth_uri
token_uri
auth_provider_x509_cert_url
client_x509_cert_url
universe_domain