Promise async, await, try, catch Example

jspromise1_async, await, try, catch.js

// https://firebase.google.com/docs/firestore/quickstart

async function main() {
  try {
    const doc = await db.doc("user/" + uid).get()

    if (doc.exists) {
      console.log("User data:", doc.data());
      // use fetched data, for example in setState()
    } else {
      console.warn("No user data.");
    }
  }
  catch(error) {
    console.log("Error getting user data:", error);
  }
}

// ...

main();