Getting all documents from one collection in Firestore

The example in the other answer is unnecessarily complex. This would be more straightforward, if all you want to do is return the raw data objects for each document in a query or collection:

async getMarker() {
    const snapshot = await firebase.firestore().collection('events').get()
    return snapshot.docs.map(doc => doc.data());
}

if you want include Id

async getMarkers() {
  const events = await firebase.firestore().collection('events')
  events.get().then((querySnapshot) => {
      const tempDoc = querySnapshot.docs.map((doc) => {
        return { id: doc.id, ...doc.data() }
      })
      console.log(tempDoc)
    })
}

Same way with array

async getMarkers() {
  const events = await firebase.firestore().collection('events')
  events.get().then((querySnapshot) => {
      const tempDoc = []
      querySnapshot.forEach((doc) => {
         tempDoc.push({ id: doc.id, ...doc.data() })
      })
      console.log(tempDoc)
   })
 }