public String getSignResponseFromServer()

in Fido/app/src/main/java/com/fido/example/fido2apiexample/GAEService.java [298:335]
31 lines of code
5 McCabe index (conditional complexity)

    public String getSignResponseFromServer(AuthenticatorAssertionResponse response) {
        Log.d(TAG, "getSignResponseFromServer");
        try {
            if (fido2Service == null) {
                return null;
            }
            JSONObject responseJson = new JSONObject();
            String clientDataJSON = new String(response.getClientDataJSON(), "UTF-8");
            String authenticatorData = BaseEncoding.base64().encode(response.getAuthenticatorData());
            String credentialId = BaseEncoding.base64Url().encode(response.getKeyHandle());
            String signature = BaseEncoding.base64().encode(response.getSignature());
            responseJson.put(KEY_CLIENT_DATA_JSON, clientDataJSON);
            responseJson.put(KEY_AUTHENTICATOR_DATA, authenticatorData);
            responseJson.put(KEY_CREDENTIAL_ID, credentialId);
            responseJson.put(KEY_SIGNATURE, signature);

            // insert sessionId for the authenticated credential ID into result data in JSON format,
            // and pass it back to server.
            String sessionId = sessionIds.get(BaseEncoding.base64Url().encode(response.getKeyHandle()));
            responseJson.put(KEY_SESSION_ID, sessionId);

            List<String> signResponseContent =
                    fido2Service.processSignResponse(responseJson.toString()).execute().getItems();
            if (signResponseContent == null || signResponseContent.isEmpty()) {
                Log.i(TAG, "signResponseContent is null or empty");
            } else {
                Log.i(TAG, "signResponseContent " + signResponseContent.get(0));
                JSONObject credential = new JSONObject(signResponseContent.get(0));
                // return string value of the authenticated credential
                return credential.toString();
            }

        } catch (IOException | JSONException e) {
            Log.e(TAG, "Error processing sign response", e);
        }

        return null;
    }