Firestore query for same value in multiple fields

Question

Is it possible to query data in cloud firestore for same value in either of multiple fields of a document.

Example like this

await firestore()
      .collection('chats')
      .where('ownerUserId', '==', user.uid)
      .where('chatUserId', '==', user.uid)
      .orderBy('createdAt', 'desc')
      .get()

or to be more precise, something like this

await firestore()
      .collection('chats')
      .where('ownerUserId', '==', user.uid || 'chatUserId', '==', user.uid)
      // .where('chatUserId', '==', user.uid)
      .orderBy('createdAt', 'desc')
      .get()

Answer 1

For an OR condition we've to do multiple queries like this:

//We define an async function that takes user uid and return chats
async function getChatsByUserOrOwner(userId) {
      const chatsRef=firestore().collection('chats')
      const ownerChats = chatsRef.where('ownerUserId', '==', userId).orderBy('createdAt', 'desc').get();
      const userChats = chatsRef.where('chatUserId', '==', userId).orderBy('createdAt', 'desc').get();  
      const [ownerChatsSnapshot, userChatsSnapshot] = await Promise.all([
              ownerChats,
              userChats
            ]);
      const ownerChatsList = ownerChatsSnapshot.docs;
      const userChatsList = userChatsSnapshot.docs;
      const allChats = ownerChatsList.concat(userChatsList);
      return allChats;
  }

Now we'll call this function to get required result:

//We call the asychronous function
getChatsByUserOrOwner(user.uid).then(result => {
    result.forEach(docSnapshot => {
        console.log(docSnapshot.data());
    });
});