Query firestore database for document id

Question

I want to query a firestore database for document id. Currently I have the following code:

db.collection(\'books\').where(\'id\', \'==\', \'fK3ddutEpD2qQqRMX         


        

Answer 1

Try this:

db.collection('books').doc('fK3ddutEpD2qQqRMXNW5').get()

(The first query is looking for an explicit user-set field called 'id', which probably isn't what you want.)

Answer 2

You can use the __name__ key word to use your document ID in a query.

Instead of this db.collection('books').doc('fK3ddutEpD2qQqRMXNW5').get() you can write

db.collection('books').where('__name__', '==' ,'fK3ddutEpD2qQqRMXNW5').get().

In this case you should get an array of length 1 back.

The firebase docs mention this feature in the rules documentation. https://firebase.google.com/docs/reference/rules/rules.firestore.Resource

Answer 3

I am a bit late, but there is actually a way to do this

db.collection('books').where(firebase.firestore.FieldPath.documentId(), '==', 'fK3ddutEpD2qQqRMXNW5').get()

This might be useful when you're dealing with firebase security rules and only want to query for the records you're allowed to access.

Answer 4

Just to clear confusion here

Remember, You should use async/await to fetch data whether fetching full collection or a single doc.

async function someFunction(){
 await db.collection('books').doc('fK3ddutEpD2qQqRMXNW5').get();
}

Answer 5

From Firestore docs for Get a document.

var docRef = db.collection("cities").doc("SF");

docRef.get().then(function(doc) {
    if (doc.exists) {
        console.log("Document data:", doc.data());
    } else {
        // doc.data() will be undefined in this case
        console.log("No such document!");
    }
}).catch(function(error) {
    console.log("Error getting document:", error);
});

Answer 6

You can get a document by its id following this pattern:

firebase
  .firestore()
  .collection("Your collection")
  .doc("documentId")
  .get()
  .then((docRef) => { console.log(docRef.data()) })
  .catch((error) => { })