如何列出Cloud Firestore文档中的子集合 [英] How to list subcollections in a Cloud Firestore document

问题描述

假设我将此最小数据库存储在Cloud Firestore中。我怎样才能检索 subCollection1 和 subCollection2 的名称？

Say I have this minimal database stored in Cloud Firestore. How could I retrieve the names of subCollection1 and subCollection2?

rootCollection {
    aDocument: {
        someField: { value: 1 },
        anotherField: { value: 2 }
        subCollection1: ...,
        subCollection2: ...,
    }
}

我希望能够只读取 aDocument 中的ID，但只有当我 get（）该文件。

I would expect to be able to just read the ids off of aDocument, but only the fields show up when I get() the document.

rootRef.doc('aDocument').get()
  .then(doc =>

    // only logs [ "someField", "anotherField" ], no collections
    console.log( Object.keys(doc.data()) )
  )

推荐答案

在节点中.js你将在'ListCollectionIds'方法之后

In Node.js you'll be after the 'ListCollectionIds' method

var firestore = require('firestore.v1beta1');

var client = firestore.v1beta1({
  // optional auth parameters.
});

// Iterate over all elements.
var formattedParent = client.anyPathPath("[PROJECT]", "[DATABASE]", "[DOCUMENT]", "[ANY_PATH]");

client.listCollectionIds({parent: formattedParent}).then(function(responses) {
    var resources = responses[0];
    for (var i = 0; i < resources.length; ++i) {
        // doThingsWith(resources[i])
    }
})
.catch(function(err) {
    console.error(err);
});

客户端SDK（Web，iOS，Android）目前不支持此功能。

This is not currently supported in the client SDKs (Web, iOS, Android).

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