Google Firestore listen for real time updates

user_8133633 0
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I have the following code that log to console all my document data. The problem is that I only receive updates as the function runs. I like to know how to setup a listener that log to console when data changes

const db = firebase.firestore();
const todoRef = db.collection("todo");

const list = (date) => {
    console.log(date);
    return todoRef
      .where("owner", "==", firebase.auth().currentUser.uid)
      .where("date", "==", date)
      .get()
      .then((querySnapshot) => {
        const data = [];
        querySnapshot.forEach((doc) => {
          const d = {
            id: doc.id,
            ...doc.data(),
          };
          data.push(d);
        });
        return data;
      });
  };

console.log("database stuff", list("2021 - 07 - 12"));
google-cloud-firestore firebase react-native javascript
1 Answers

There's a listen to multiple documents section in the documentation.

db.collection("cities").where("state", "==", "CA")
    .onSnapshot((querySnapshot) => {
        var cities = [];
        querySnapshot.forEach((doc) => {
            cities.push(doc.data().name);
        });
        console.log("Current cities in CA: ", cities.join(", "));
    });

You just need to use onSnapshot instead of get.

user_131306970
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