缓存服务人员的帖子请求

Question

如何缓存POST请求？我能够缓存所有GET请求，但无法缓存POST。我正在为我的应用程序实现脱机功能。

我尝试了以下代码，但是没有运气

self.addEventListener('fetch', function(event) {
  event.respondWith(caches.match(event.request).then(function(response) {console.log('fetch' +response);
    // caches.match() always resolves
    // but in case of success response will have value
    if (response !== undefined) {
      return response;
    } else {
      return fetch(event.request).then(function (response) {
        // response may be used only once
        // we need to save clone to put one copy in cache
        // and serve second one
        let responseClone = response.clone();

        caches.open('v1').then(function (cache) {
          cache.put(event.request, responseClone);
        });
        return response;
      }).catch(function () {
        return caches.match('/sw-test/gallery/myLittleVader.jpg');
      });
    }
  }));
});