Question

我正在尝试从可调用的Google Cloud Function返回QuerySnapshot。

下面是细节，但我的核心问题是，我应该期望能够做到这一点还是这是一个错误？

import * as admin from 'firebase-admin';
import * as functions from 'firebase-functions';
import * as firestore from '@google-cloud/firestore';

export const callableTest = functions.https.onCall(
    async (data: Map<string, any>, context: functions.https.CallableContext):
        Promise<firestore.QuerySnapshot> => {
        const db = admin.firestore();
        return db.collection('test')
            .get();

        // I also tried this
        //return db.collection('test').get().then(querySnapshot => {
        //    return querySnapshot;
        //});
    });

test集合可以包含任意数量的文档。在这种情况下，有两个文档。

这是我的客户端HTML页面，但我也在Flutter和Node中尝试了同样的结果。

<!DOCTYPE html>
<html>
    <head>
      <script src="https://www.gstatic.com/firebasejs/5.7.3/firebase.js"></script>
      <script>
        // Initialize Firebase
        var config = {
          apiKey: "### API KEY ###",
          authDomain: "<project-id>.firebaseapp.com",
          databaseURL: "https://<project-id>.firebaseio.com",
          projectId: "<project-id>",
          storageBucket: "<project-id>.appspot.com",
          messagingSenderId: "<sender-id>"
        };
        firebase.initializeApp(config);

        var testClientCall = firebase.functions().httpsCallable('callableTest');
        testClientCall ({}).then(function(result) {
          // Read result of the Cloud Function.
          console.log("Cloud Function result:");
          console.log(result);
        });
      </script>
    </head>
    <body></body>
</html>

这是返回的结果，它看起来像QuerySnapshot ，但不包含任何DocumentSnapshots（_docs属性），即使{{ 1}}属性指示应该有两个文档。

_size

起初，我认为序列化可能是一个问题，但是如果我修改云函数以仅返回单个{"data":{"_query":{"_firestore":{"_clientPool":{"concurrentOperationLimit":100,"clientFactory":{},"activeClients":{}},"_settings":{"projectId":"<project-id>","firebaseVersion":"6.4.0","libName":"gccl","libVersion":"0.19.0 fire/6.4.0"},"_settingsFrozen":false,"_clientInitialized":{"domain":{"domain":null,"_events":{"error":{}},"_eventsCount":1,"_maxListeners":null,"members":[]}},"_serializer":{"createReference":{},"timestampsInSnapshots":false},"_referencePath":{"segments":[],"projectId":"project-id","databaseId":"(default)"},"_lastSuccessfulRequest":1547738645649,"_validator":{"isFunction":{},"isOptionalFunction":{},"isInteger":{},"isOptionalInteger":{},"isNumber":{},"isOptionalNumber":{},"isObject":{},"isOptionalObject":{},"isString":{},"isOptionalString":{},"isBoolean":{},"isOptionalBoolean":{},"isArrayElement":{},"isOptionalArrayElement":{},"isDeletePrecondition":{},"isOptionalDeletePrecondition":{},"isDocument":{},"isOptionalDocument":{},"isDocumentReference":{},"isOptionalDocumentReference":{},"isFieldPath":{},"isOptionalFieldPath":{},"isFieldValue":{},"isOptionalFieldValue":{},"isFieldOrder":{},"isOptionalFieldOrder":{},"isQueryComparison":{},"isOptionalQueryComparison":{},"isQueryValue":{},"isOptionalQueryValue":{},"isResourcePath":{},"isOptionalResourcePath":{},"isSetOptions":{},"isOptionalSetOptions":{},"isReadOptions":{},"isOptionalReadOptions":{},"isUpdateMap":{},"isOptionalUpdateMap":{},"isUpdatePrecondition":{},"isOptionalUpdatePrecondition":{}},"_preferTransactions":true},"_path":{"segments":["test"],"projectId":"project-id","databaseId":"(default)"},"_fieldFilters":[],"_fieldOrders":[],"_queryOptions":{},"_validator":{"isFunction":{},"isOptionalFunction":{},"isInteger":{},"isOptionalInteger":{},"isNumber":{},"isOptionalNumber":{},"isObject":{},"isOptionalObject":{},"isString":{},"isOptionalString":{},"isBoolean":{},"isOptionalBoolean":{},"isArrayElement":{},"isOptionalArrayElement":{},"isDeletePrecondition":{},"isOptionalDeletePrecondition":{},"isDocument":{},"isOptionalDocument":{},"isDocumentReference":{},"isOptionalDocumentReference":{},"isFieldPath":{},"isOptionalFieldPath":{},"isFieldValue":{},"isOptionalFieldValue":{},"isFieldOrder":{},"isOptionalFieldOrder":{},"isQueryComparison":{},"isOptionalQueryComparison":{},"isQueryValue":{},"isOptionalQueryValue":{},"isResourcePath":{},"isOptionalResourcePath":{},"isSetOptions":{},"isOptionalSetOptions":{},"isReadOptions":{},"isOptionalReadOptions":{},"isUpdateMap":{},"isOptionalUpdateMap":{},"isUpdatePrecondition":{},"isOptionalUpdatePrecondition":{}},"_serializer":{"createReference":{},"timestampsInSnapshots":false}},"_readTime":{"_seconds":1547738645,"_nanoseconds":638303000},"_size":2,"_materializedDocs":null,"_materializedChanges":null,"_docs":{},"_changes":{},"_validator":{"isFunction":{},"isOptionalFunction":{},"isInteger":{},"isOptionalInteger":{},"isNumber":{},"isOptionalNumber":{},"isObject":{},"isOptionalObject":{},"isString":{},"isOptionalString":{},"isBoolean":{},"isOptionalBoolean":{},"isArrayElement":{},"isOptionalArrayElement":{},"isDeletePrecondition":{},"isOptionalDeletePrecondition":{},"isDocument":{},"isOptionalDocument":{},"isDocumentReference":{},"isOptionalDocumentReference":{},"isFieldPath":{},"isOptionalFieldPath":{},"isFieldValue":{},"isOptionalFieldValue":{},"isFieldOrder":{},"isOptionalFieldOrder":{},"isQueryComparison":{},"isOptionalQueryComparison":{},"isQueryValue":{},"isOptionalQueryValue":{},"isResourcePath":{},"isOptionalResourcePath":{},"isSetOptions":{},"isOptionalSetOptions":{},"isReadOptions":{},"isOptionalReadOptions":{},"isUpdateMap":{},"isOptionalUpdateMap":{},"isUpdatePrecondition":{},"isOptionalUpdatePrecondition":{}}}}，则会返回预期的数据。

Answer 1

这是序列化的问题。您正在尝试返回一个不打算直接序列化的复杂对象。相反，您应该迭代查询快照中的文档，构建要返回的任何对象（数组？），然后返回该对象。像这样：

const querySnapshot = await db.collection('test').get();
return querySnapshot.docs.map(doc => doc.data());

从可调用的云函数返回QuerySnapshot

1 个答案: