Angular 5中Firestore写入问题：Stripe checkout数据存错库

Let's walk through fixing your Cloud Function — there are several Firestore API mismatches and path errors in your current code that are preventing data from being saved to Firestore correctly. Here's the corrected implementation:

const functions = require('firebase-functions');
const admin = require('firebase-admin');
admin.initializeApp(); // No need to pass config if using the default service account
const db = admin.firestore();
const stripe = require('stripe')(functions.config().stripe.testkey);

// Trigger on writes to a payment document under payments/{userId}/{paymentId}
exports.stripeCharge = functions.firestore
  .document('payments/{userId}/{paymentId}')
  .onWrite(async (change, context) => {
    // Get the payment data from the Firestore document
    const payment = change.after.data();
    const userId = context.params.userId;
    const paymentId = context.params.paymentId;

    // Exit if payment doesn't exist or has already been charged
    if (!payment || payment.charge) return null;

    try {
      // Fetch the customer data (adjust this path if your customer data lives elsewhere)
      const customerDoc = await db.collection('payments').doc(userId).get();
      if (!customerDoc.exists) {
        throw new Error(`Customer document for userId ${userId} not found`);
      }
      const customer = customerDoc.data();

      const amount = payment.amount;
      const idempotency_key = paymentId;
      const source = payment.token.id; // Fixed typo: was payment.testkey.id, should match your frontend token field
      const currency = 'php';

      // Create Stripe charge
      const charge = await stripe.charges.create(
        { amount, currency, source },
        { idempotency_key }
      );

      // Update the payment document in Firestore with the charge data
      await db
        .collection('payments')
        .doc(userId)
        .collection('payments') // Matches your original database structure
        .doc(paymentId)
        .update({ charge: charge });

      return null;
    } catch (error) {
      // Handle errors (you could also write the error to Firestore for debugging)
      console.error('Stripe charge error:', error);
      throw error;
    }
  });

Key Fixes Explained: #

• Trigger Path Correction
  Changed the trigger to payments/{userId}/{paymentId} to mirror your original Realtime Database hierarchy in Firestore. This ensures we listen to writes on individual payment documents under each user's subcollection.

• Firestore API Replacements
  Swapped Realtime Database-specific methods like event.data.val() with Firestore's change.after.data() (to fetch updated document data) and context.params (to access wildcard values like userId/paymentId). Replaced once('value') with Firestore's get() for document reads, and used data() instead of val() to extract content.

• Variable Paths Instead of Literals
  Fixed paths like doc('{userId}') to doc(userId) — your original code was using hardcoded strings instead of the actual parameter values.

• Correct Update Method
  Replaced the invalid .field('charge').set(charge) with .update({ charge: charge }) (or use .set({ charge }, { merge: true }) if preferred) to properly save the Stripe charge data to the payment document.

• Typo & Readability Fixes
  Corrected payment.testkey.id to payment.token.id (matching your original database's token object structure) and rewrote promise chains to use async/await for cleaner, easier-to-debug code.

Matching Firestore Structure #

Your Firestore setup will now match your original Realtime Database structure:

payments (collection)
  └── {userId} (document)
      └── payments (subcollection)
          └── {paymentId} (document)
              ├── amount: number
              ├── token: object
              └── charge: object

内容的提问来源于stack exchange，提问作者ziggy