从集合中获取所有文档

Question

我想从一个集合中得到所有的文件，然后用它们，得到他们的身份证。这里我的集合如何是用户集合，它只是一个集合和多个文档。我试了一下，但不起作用：

let userRef = admin.firestore().collection('users');
      return userRef.get().then(querySnapshot => {
        let docs = querySnapshot.docs;
        for (let doc of docs) {
           console.log(doc.id);
        }
        return true;
      });

更新

let savedRef = await admin.firestore().collection('saved');
        return savedRef.get().then(querySnapshot => {
          console.log(querySnapshot);
          let docs = querySnapshot.docs;
          for (let doc of docs) {
             console.log(doc.id);
          }
          return true;
        });

Answer 1

是的，QuerySnapshot可以很容易地迭代自己并得到您想要的内容。这就是我通常迭代Firestore查询快照的方式：

//I like to separate DB instance for re-utilization
var db = admin.firestore()

//Also a good practice to separate reference instance
var usersReference = db.collection("users");

//Get them
usersReference.get().then((querySnapshot) => {

    //querySnapshot is "iteratable" itself
    querySnapshot.forEach((userDoc) => {

        //userDoc contains all metadata of Firestore object, such as reference and id
        console.log(userDoc.id)

        //If you want to get doc data
        var userDocData = userDoc.data()
        console.dir(userDocData)

    })

})