Introduction

Retrieving multiple documents from a Firestore query typically involves processing a query snapshot. The readQuerySnapshot function streamlines this process by transforming a query snapshot into an easily manageable array of document data objects, each including the document ID.

Key Features

  • Simplified Data Extraction: Converts query snapshots into an array of data objects with document IDs.
  • Excludes Non-Existent Documents: Automatically filters out documents that do not exist, ensuring data integrity.
  • Type Safety with Generics: Supports generic typing for document data, enhancing type safety and reducing errors.

Utilization

Preparing for Query Snapshot Reads

Import readQuerySnapshot to handle Firestore query snapshot processing:

import { firestore } from 'firebase-admin'
import { readQuerySnapshot } from 'path-to-your-utilities'

// Assuming 'querySnapshot' is obtained from a Firestore query
const querySnapshot: firestore.QuerySnapshot = firestore()
  .collection('path/to/collection')
  .get()

Extracting Data Array from a Query Snapshot

Use readQuerySnapshot to process the query snapshot into an array of document data objects:

// Process the query snapshot
const documentsArray = readQuerySnapshot(querySnapshot)

// 'documentsArray' contains an array of objects, each with document data and ID

Handling Empty or Non-Existent Documents

readQuerySnapshot ensures that only existing documents are included in the returned array, skipping any documents that are not found in the database.

Best Practices

  • Utilize readQuerySnapshot for batch data retrieval from Firestore to ensure consistent data handling.
  • Leverage the generic typing feature to maintain type safety across your Firestore data processing.
  • Always verify the returned array, especially in cases where the query might return no documents.

Be mindful of Firestore’s performance and rate limits when handling large query snapshots. Optimize your queries to fetch only necessary data.