firestore-add-data.js

//  Add a first document with a generated ID.
db.collection("users").add({
  first: "Ada",
  last: "Lovelace",
  born: 1815
})
.then((docRef) => {
  console.log("Document written with ID: ", docRef.id);
})
.catch((error) => {
  console.error("Error adding document: ", error);
});

//  Add a second document with a generated ID.
db.collection("users").add({
  first: "Alan",
  middle: "Mathison",
  last: "Turing",
  born: 1912
})
.then((docRef) => {
   console.log("Document written with ID: ", docRef.id);
})
.catch((error) => {
  console.error("Error adding document: ", error);
});