Trouble with promise in firebase functions - node.js

Question

This code either runs once or a max of 100 times. I have a dummy data file with 6000 records as this is the average that it will have to handle.
Currently using the Blaze plan.
The code was working somewhat, I set up a new project and now I get this issue.
export const uploadPatrons = functions.storage
.object()
.onFinalize((object, context) => {
let patronPromise: any[];
patronPromise = [];
if (object.name === 'patrons/upload.csv') {
admin
.storage()
.bucket()
.file('/patrons/upload.csv')
.download({})
.then(data => {
Papa.parse(data.toString(), {
header: true,
skipEmptyLines: true,
complete: result => {
result.data.forEach(x => {
x.inside = false;
x.arrived = false;
x.img = false;
x.arrivedTime = null;
const newPromise = admin
.firestore()
.collection('patrons')
.add({ ...x })
.then(doc => {
console.log(doc);
})
.catch(err => {
console.log(err);
});
patronPromise.push(newPromise);
});
}
});
})
.catch(err => {
console.log(err);
});
}
return Promise.all(patronPromise)
.catch(err => {
console.log(err);
});
});
All it has to do is read the file from the storage, parse it and add each record to the firebase collection
Function returned undefined, expected Promise or value
This is the error I get in the logs

Answer 1

Because of your first promise may be shutdown even it not finish. So try to follow the rule promise/always-return
export const uploadPatrons = functions.storage
.object()
.onFinalize((object, context) => {
if (object.name === 'patrons/upload.csv') {
return admin.storage().bucket()
.file('/patrons/upload.csv')
.download({})
.then(data => {
let patronPromise: any[];
patronPromise = [];
Papa.parse(data.toString(), {
header: true,
skipEmptyLines: true,
complete: result => {
result.data.forEach(x => {
x.inside = false;
x.arrived = false;
x.img = false;
x.arrivedTime = null;
const newPromise = admin.firestore()
.collection('patrons')
.add({
...x
})
patronPromise.push(newPromise);
});
}
});
return Promise.all(patronPromise)
})
.then(result=>{
//return Promise.resolve or something
})
.catch(err=>{
console.log(err)
})
}
else{
//also return if it's nothing
}
});

Answer 2

You're ignoring the promise that admin.storage().bucket().file('/patrons/upload.csv').download({}) returns, which means that the function may get aborted.
I think it should be closer to this:
export const uploadPatrons = functions.storage
.object()
.onFinalize((object, context) => {
let patronPromise: any[];
patronPromise = [];
if (object.name === 'patrons/upload.csv') {
return admin.storage().bucket()
.file('/patrons/upload.csv')
.download({})
.then(data => {
Papa.parse(data.toString(), {
header: true,
skipEmptyLines: true,
complete: result => {
result.data.forEach(x => {
x.inside = false;
x.arrived = false;
x.img = false;
x.arrivedTime = null;
const newPromise = admin.firestore()
.collection('patrons')
.add({
...x
})
patronPromise.push(newPromise);
});
// TODO: return the Promise.all(patronPromise) here
}
});
})
}
});