Firebase 9 - Firestore Method Cheat Sheet
5 min read
jdgamble555 on (last modified on )
Mutations
// add doc
await setDoc(doc(db, "pathname"), data);
// upsert doc
await setDoc(doc(db, "pathname"), data, { merge: true });
// update doc
await updateDoc(doc(db, "pathname"), data);
// add item to array
await updateDoc(doc(db, "pathname"), { arrayname: arrayUnion("new value") });
// remove item from array
await updateDoc(doc(db, "pathname"), { arrayname: arrayRemove("old value") });
// increment a number
await updateDoc(doc(db, "pathname"), { counter: increment(1) });
// decrement a number
await updateDoc(doc(db, "pathname"), { counter: increment(-1) });
// delete a doc
await deleteDoc(doc(db, "pathname"));
// create an id
const id = doc(collection(db, 'id')).id;Queries
// get a doc
const docSnap = await getDoc(doc(db, "pathname"));
const data = docSnap.exists() ? { ...docSnap.data(), id: docSnap.id } : null;
// get multiple docs
const querySnap = await getDocs(query(collection(db, "pathname"), ...filters));
for (const doc of querySnap.docs) {
const data = doc.exists() ? { ...doc.data(), id: doc.id } : null;
...
}
// get collection Group multiple docs
const querySnap = await getDocs(query(collectionGroup(db, "pathname"), ...filters);
for (const doc of querySnap.docs) {
const data = doc.exists() ? { ...doc.data(), id: doc.id } : null;
...
}
// filters
where(field, comparison, value)
orderBy(field, "desc|asc")
limit(1)
// cursors using field or docSnap
startAt()
startAFter()
endAt()
endBefore()
// comparisons
"<", "<=", "==", ">", ">=", "!="
// array comparisons
"array-contains", "array-contains-any", "in", "not-in"Realtime Queries
// get a doc
const unsub = onSnapshot(doc(db, "pathname"), doc => {
const data = doc.exists() ? { ...doc.data(), id: doc.id } : null;
...
});
// get multiple docs (query is optional)
const unsub = onSnapshot(query(collection(db, "pathname"), ...filters), querySnap => {
for (const doc of querySnap.docs) {
const data = doc.exists() ? { ...doc.data(), id: doc.id } : null;
...
}
...
});
Batches and Transactions
// execute a transaction
const txData = await runTransaction(db, async (transaction) => {
const docRef = doc(db, "pathname");
const docSnap = await transaction.get(docRef);
const data = docSnap.exists() ? { ...doc.data(), id: doc.id } : null;
const new_data = { ... };
// await not necessary due to tx
transaction.update(docRef, new_data);
// return new data
return { ... };
});
// batch writes
const batch = writeBatch(db);
const docRef = doc(db, "pathname");
const docRef2 = doc(db, "pathname2");
const docRef3 = doc(db, "pathname3");
batch.set(docRef, { ... });
batch.update(docRef2, { ... });
batch.delete(docRef3);
await batch.commit();Note
All the above methods should be used within try / catch blocks for error checking. All of the unsub methods should be called within your framework's onDestroy methods to prevent memory leaks.
RXFire / Angular Fire
// get a doc
const unsub = docData(doc(db, "pathname"), { idField: 'id' })
.subscribe(doc => {
});
// get multiple docs
const unsub = collectionData(query(collection(db, "pathname"), ...filters), { idField: 'id'})
.subscribe(docs => {
});
// get a doc snap
const unsub = docSnapshots(doc(db, "pathname"), { idField: 'id' })
.subscribe(doc => {
});
// get a collection snap
const unsub = collectionChanges(query(collection(db, "pathname"), ...filters), { idField: 'id'})
.subscribe(docs => {
});J
firebase
cloud-firestore