I have this code:

import { defineString } from 'firebase-functions/params'
import { onMessagePublished } from 'firebase-functions/v2/pubsub'
import { firestore } from '~/providers'

const topic = defineString('TRANSCODER_TOPIC')

export const onTranscoder = onMessagePublished(topic.value(), async (event) => {
  const {
    job: { name, state },
  } = event.data.message.json

  const queryRef = firestore.collection('videos').where('transcoder.job', '==', name).limit(1)
  const snapshot = await queryRef.get()
  const ready = state === 'SUCCEEDED'

  await firestore.collection('videos').doc(snapshot.docs[0].id).set({ transcoder: { ready } }, { merge: true })
})

When I deploy it, I get several errors, which, not surprisingly, do not tell me the specific line causing the issue—typical of Google’s error messages.

If I follow the suggestion and change the code to:

export const onTranscoder = onMessagePublished(topic, async (event) => {

I get an error because onMessagePublished requires a string.

Am I going crazy? How can I resolve this?

Google is forcing everyone to migrate to Firebase Functions V2 but fails to provide complete migration documentation, missing APIs, etc.