What is the solution for breaking a querySnapshot in Firestore?

Is there a way to exit a querysnapshot loop prematurely?

I attempted using a for loop, but I keep encountering the following error message.

How can this error be resolved or is there an alternative method to break out of a snapshot loop?

code

  return query.get()
    .then((snapshot) => {
      for(const doc of snapshot) {
        let data = doc.data()
        if (data.age == 16) {
            break;
        }
  }

error

Type 'QuerySnapshot' must have a 'Symbol.iterator' method that returns an iterator.

typescriptfirebasegoogle-cloud-platformgoogle-cloud-firestore

Answer №1

To access all the documents in a QuerySnapshot, you can utilize the docs property.

One approach is to use a for loop:

  return query.get()
    .then((snapshot) => {
      const snapshotsArray = snapshot.docs;
      for (var i = 0; i < snapshotsArray.length; i++) {
        const data = snapshotsArray[i].data()
        if (data.age == 16) {
            break;
        }
      }
    });

Alternatively, you can employ a for-of loop:

  return query.get()
    .then((snapshot) => {
      const snapshotsArray = snapshot.docs;
      for (const snap of snapshotsArray) {
        const data = snap.data()
        if (data.age == 16) {
            break;
        }
      }
    });

Answer №2

Documentation states that QuerySnapshot<T> does not function as an iterator/async iterator, thus limiting its usage. It appears that the only method available for iterating over it is via the forEach function, which lacks support for "early breaking".

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