Question

I’m doing authentication of android app against an app engine server, basically following this post: http://blog.notdot.net/2010/05/Authenticating-against-App-Engine-from-an-Android-app.

It appears that the cookie that I get at the end of the process is no good – I’m getting 401, so I tried copying the cookie and testing it in the browser, and still getting 401. When copying the browser cookie to the android app, the request works.

How could I be getting an invalid cookie? I’ve even tried invalidating the tokens, but still getting the same result…

Answer 1

For some reason this worked: I changed the URL for the initial cookie request from https to http, then changed it back.

But in the end I decided to change my implementation and go with loopj as alistair suggested. The result is far more elegant. This is my login activity (note that I’m connecting the client to a persistent cookie storage given by loopj api):

public class AccountList extends ListActivity {
    protected AccountManager accountManager;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        accountManager = AccountManager.get(getApplicationContext());
        Account[] accounts = accountManager.getAccountsByType("com.google");
        this.setListAdapter(new ArrayAdapter<Account>(this, R.layout.list_item, accounts));   
    }

    @Override
    protected void onListItemClick(ListView l, View v, int position, long id) {
        Account account = (Account)getListView().getItemAtPosition(position);
        accountManager.invalidateAuthToken("com.google", null);
        accountManager.getAuthToken(account, "ah", null, this, new GetAuthTokenCallback(), null);
    }

    private class GetAuthTokenCallback implements AccountManagerCallback<Bundle> {
        public void run(AccountManagerFuture<Bundle> result) {
            AsyncHttpClient client = new AsyncHttpClient();
            PersistentCookieStore myCookieStore = new PersistentCookieStore(getBaseContext());
            client.setCookieStore(myCookieStore);
            try {
                Bundle bundle;
                bundle = result.getResult();
                Intent intent = (Intent)bundle.get(AccountManager.KEY_INTENT);
                if(intent != null) {
                    // User input required
                    startActivity(intent);
                } else {
                    String token = bundle.getString(AccountManager.KEY_AUTHTOKEN);
                    String url = "http://myapp.appspot.com/_ah/login?continue=http://localhost/&auth=" + token;
                    client.post(url, new AsyncHttpResponseHandler());
                    Intent backToMainActivity = new Intent(getApplicationContext(), MainActivity.class);
                    startActivity(backToMainActivity);
                }
            } catch (OperationCanceledException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (AuthenticatorException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }
}

Because loopj gives persistent cookie storage, all I have to do in another activity is to initialize a client and connect it with the persistent cookie storage. This gives the new client all of the cookies I got from the login activity. Initialization looks something like this:

AsyncHttpClient client = new AsyncHttpClient();
client.setCookieStore(new PersistentCookieStore(this));

BTW & FYI: The loopj library uses the SharedPreferences API in order to store the cookies, and wraps it nicely as PersistentCookieStore.