Helper for batching operations in Firestore

FirestoreBatcher.js

export class FirestoreBatcher {
  batches = [];
  index = 0;

  constructor(firestore) {
    this.firestore = firestore;
  }

  getNext() {
    if (this.index++ % 500 === 0) {
      this.batches.push(this.firestore.batch());
    }

    return this.batches[this.batches.length - 1];
  }

  async commit() {
    await Promise.all(this.batches.map(batch => batch.commit()));
  }

  delete(ref) {
    this.getNext().delete(ref);
  }

  set(ref, data) {
    this.getNext().set(ref, data);
  }

  update(ref, data) {
    this.getNext().update(ref, data);
  }
}

Usage:

const batch = new FirestoreBatcher(firebase.firestore());

batch.set(
  firebase
    .firestore()
    .collection("users")
    .doc(USER_ID),
  { name: "Charles" }
);

await batch.commit();