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ViewsFirebase undefined error when array is empty
Hi so I have this function that counts how many time a name appears in a list:
fire.firestore()
.collection("eventLikes")
.doc(eventID)
.onSnapshot((docSnapshot) => {
//}
// if(docSnapshot.data().ActivityLikes.length === 0) {
const nameCounts = docSnapshot.data().ActivityLikes.reduce((acc, cur) => {
acc[cur.name] = (acc[cur.name] || 0) + 1;
return acc;
}, {});
docSnapshot.data() is empty at the start and docSnapshot.data().ActivityLikes.length is sometimes empty so [] in firebase. But in NextJs i keep gettin this error:
How should i go about fixing this error?
·
Juan Pablo Isaza
1 answers
Answer question0
If the document doesn't exist then .data() returns undefined. You should if that exists first:
if (docSnapshot.exists) {
// process data
} else {
console.log("Document does not exists")
}
·
Juan Pablo Isaza
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