Handle Promises in a Batch write in Firebase cloud function

Question

I am using following function in my firebase functions, but i am unable to handle promises correctly.

export const addNewMember_v0 = functions.https.onCall( async (data, context) => {
    if(context.auth){
        const memberName = data.memberName;
        const phone = data.phone;

        try {
            const querySnapshot = await db.collectionGroup('memberPrivate')
                .where('phone', '==', phone).get();
            if (querySnapshot === null) {
                const batch = db.batch();
                const memberDoc = db.collection('members').doc();
                const memberPrivateDoc = memberDoc.collection("memberPrivate").doc("info");

                batch.set(
                    memberDoc,
                    {'memberName':memberName},
                );

                batch.set(
                    memberPrivateDoc,
                    {'memberName':memberName}
                );

                Promise.resolve(batch.commit());
                return {available: true,  phone: phone, success: true};

            } else {
                return {available: false,  phone: phone, success: false};
            }
        }
        catch(error) {
            console.log(error);
            return {error: error, success: false};
        }        
    } else {
        return {error: "Not Authenticated", success: false};
    }
});

When i am deploying this code using firebase deploy, i am getting this error: Promises must be handled appropriately

What should i change to handle promises correctly?

I read many docs about how to handle Promises, but i haven't been able to do it. If you could help, it would be really great.

Does this answer your question? [What could this be about? \[TsLint Error: "Promises must be handled appropriately"\]](https://stackoverflow.com/questions/43980188/what-could-this-be-about-tslint-error-promises-must-be-handled-appropriately) — machineghost, Apr 15 '20 at 00:16
Not sure why you're calling Promise.resolve(). That doesn't fit at all here. Your function also needs to return a promise that resolves with the data to send to the caller. — Doug Stevenson, Apr 15 '20 at 00:28

score 0 · Answer 1 · answered Apr 15 '20 at 00:36

0

batch.commit appears to be an asynchronous function, so change

Promise.resolve(batch.commit());

to

await batch.commit();

answered Apr 15 '20 at 00:36

robdonn

250
3
11

score 0 · Accepted Answer · answered Apr 15 '20 at 00:49

I solved it by using following

try{
    if(condition){
        const fetchPromises: Promise<any>[] = [];

        fetchPromises.push(batch.commit());
        fetchPromises.push(Promise.resolve({available: true,  phone: phone, success: true}));
        return Promise.all(fetchPromises);
    }
}

Handle Promises in a Batch write in Firebase cloud function

2 Answers2