loginActions.js

function loginSuccess (router) {
  return (dispatch, getState) => {
    const state = getState();
    console.log('test');

    let nextPath = state.router.query ? state.router.query.next : '/home';
    // TODO: Swap these two, when React 0.14 is released.
    // dispatch(transitionTo(state.router.query.next));
    router.transitionTo(nextPath);
  };
}

export function login (email, password, router) {
  return {
    types: [LOGIN, LOGIN_SUCCESS, LOGIN_ERROR],
    payload: {
      promise: authenticate(email, password),
      onSuccessAction: loginSuccess(router)
    }
  };
}