从 Google Cloud Datastore 中删除实体

Question

I'm having trouble deleting entities from the Google Cloud Datastore using node.js. I suspect I'm missing something really basic because this should not be hard.

I get the keys only as per this documentation :

const query = datastore.createQuery('coin').select('__key__');

Run the query:

const [keys] = await datastore.runQuery(query);

Delete the resulting entities by key as per this documentation :

datastore.delete(keys);

But I get "InvalidKey: A key should contain at least a kind."

If I do console.log(keys) right after running the query there is indeed an array of what appear to be key results with a valid kind:

 [
  {
    [Symbol(KEY)]: Key {
      namespace: undefined,
      id: '5083500323536896',
      kind: 'coin',
      path: [Getter]
    }
  },
  {
    [Symbol(KEY)]: Key {
      namespace: undefined,
      id: '5130717650485248',
      kind: 'coin',
      path: [Getter]
    }
  },
etc...

Is the above not the array.delete() is expecting?

Answer 1

Thanks to this post I realized the results of a keys only query are not an array of keys, but are rather an array of keys stored under a symbol property. It's obvious now when I look at the output, but it was so unexpected I didn't think of it.

So in order to run delete() on an array of keys I need to extract just the key from each result like this:

const justTheKeys = keys.map(function(res) {
     return res[datastore.KEY];
});

Then I can finally delete the entities:

datastore.delete(justTheKeys);