I want to aggregate firestore data but I want to go with netlify lambda for the serverless functions. I want to do something like

onst functions = require('firebase-functions');
const admin = require('firebase-admin');
admin.initializeApp();

exports.aggregateComments = functions.firestore
    .document('posts/{postId}/comments/{commentId}')
    .onWrite(event => {

    const commentId = event.params.commentId; 
    const postId = event.params.postId;
    
    // ref to the parent document
    const docRef = admin.firestore().collection('posts').doc(postId)
    
    // get all comments and aggregate
    return docRef.collection('comments').orderBy('createdAt', 'desc')
         .get()
         .then(querySnapshot => {

            // get the total comment count
            const commentCount = querySnapshot.size

            const recentComments = []

            // add data from the 5 most recent comments to the array
            querySnapshot.forEach(doc => {
                recentComments.push( doc.data() )
            });

            recentComments.splice(5)

            // record last comment timestamp
            const lastActivity = recentComments[0].createdAt

            // data to update on the document
            const data = { commentCount, recentComments, lastActivity }
            
            // run update
            return docRef.update(data)
         })
         .catch(err => console.log(err) )
});

but I can't get it to work on netlify lambda. Is there anyway I can use this function in netlify lambda?

CodePudding user response：

You cannot deploy Firebase Cloud Functions to any other provider. Other environments might be totally different and may not have all the credentials/env variables required.

If you want to listen for realtime updates outside of GCP, you can try using Firestore's onSnapshot() but you'll need a server that runs always. The listener will stop once you serverless functions terminates.