swift - 过去 7 天最喜欢的商品？

Question

我正在为我的应用使用 Firestore，并且希望能够获得过去 7 天内发布的最受欢迎的项目。在理想的情况下，调用看起来像这样:

        let calendar = Calendar.current
        let components = calendar.dateComponents([.year, .month, .day], from: Date())
        let start = calendar.date(from: components)!
        let startDate = calendar.date(byAdding: .day, value: -7, to: start)!
        let startDateStamp: Timestamp = Timestamp(date: startDate)

        let mostLiked = colRef
        .whereField("isReported", isEqualTo: false)
        .whereField("timestamp", isGreaterThanOrEqualTo: startDateStamp)
        .order(by: "likeCount", descending: true)
        .limit(to: 1)

        mostLiked.getDocuments { (snapshot, error) in
            if let error = error { return }
            guard let snap = snapshot else { return }

            for document in snap.documents {
                let data = document.data()
                print(data)
            }
        }

但这显然是不允许的。

我最终得到:

        let calendar = Calendar.current
        let components = calendar.dateComponents([.year, .month, .day], from: Date())
        let start = calendar.date(from: components)!
        let startDate = calendar.date(byAdding: .day, value: -7, to: start)!
        let startDateStamp: Timestamp = Timestamp(date: startDate)

        let mostLiked = colRef
        .whereField("isReported", isEqualTo: false)
        .whereField("timestamp", isGreaterThanOrEqualTo: startDateStamp)
        .order(by: "timestamp", descending: true)

        mostLiked.getDocuments { (snapshot, error) in
            if let error = error { return }
            guard let snap = snapshot else { return }

            for document in snap.documents {
                let data = document.data()
                ...
                 data handling code to fill struct - newTopItem
                ...

                if self.topLikedArray.isEmpty {
                    self.topLikedArray.append(newTopItem)
                } else {
                    if likeCount > self.topLikedArray[0].likeCount! {
                        self.topLikedArray.removeAll()
                        self.topLikedArray.append(newTopItem)
                    }
                }
            }
           print("Top Item: \(self.topLikedArray)")
        }

它会获取过去 7 天内的所有内容，我必须手动排序才能获得最大 LikeCount，这对我来说似乎有点笨拙，更不用说它带来的可扩展性问题，因为我无法将结果限制为只是1.有更好的方法吗？

Answer 1

    let mostLiked = bleatsRef
        .whereField("isReported", isEqualTo: false)
        .whereField("timestamp", isGreaterThanOrEqualTo: startDateStamp)
        .order(by: "likeCount", descending: true)
        .limit(1)

    mostLiked.getDocuments { (snapshot, error) in
        guard
            error == nil, 
            let snap = snapshot 
            else { return }

        print("The most liked document is: \(snap.documents.first)")
    }