SwiftyJSON Performance vấn đề

Question

Tôi đang gặp vấn đề hiệu suất nghiêm trọng phân tích cú pháp JSON với SwiftyJson từ API của chúng tôi và đưa vào các dữ liệu cốt lõi.

Các dữ liệu sẽ được tải về với Alamofire, mà công trình độc đáo nhưng phân tích cú pháp JSON với SwiftyJson là đau đớn chậm. Để xem nếu thư viện thực sự là vấn đề tôi viết lại phân tích cú pháp json ở một trong nhiều nơi dữ liệu được phân tích cú pháp. Trong đoạn code dưới đây tôi phân tích các giờ mở cửa của một trong khoảng 400 điểm du lịch.

Thấy sự khác biệt trong các ảnh chụp màn hình, 7,7 giây đến 185 ms:

Các Swifty cách:

let openDescription:String = json["OpeningHours"]["OpeningHoursGenericExceptions"].string! 
    let monOpen:[String] = json["OpeningHours"]["Monday"]["From"].string!.componentsSeparatedByString(":") 
    let monClose:[String] = json["OpeningHours"]["Monday"]["To"].string!.componentsSeparatedByString(":") 
    let tueOpen:[String] = json["OpeningHours"]["Tuesday"]["From"].string!.componentsSeparatedByString(":") 
    let tueClose:[String] = json["OpeningHours"]["Tuesday"]["To"].string!.componentsSeparatedByString(":") 
    let wedOpen:[String] = json["OpeningHours"]["Wednesday"]["From"].string!.componentsSeparatedByString(":") 
    let wedClose:[String] = json["OpeningHours"]["Wednesday"]["To"].string!.componentsSeparatedByString(":") 
    let thuOpen:[String] = json["OpeningHours"]["Thursday"]["From"].string!.componentsSeparatedByString(":") 
    let thuClose:[String] = json["OpeningHours"]["Thursday"]["To"].string!.componentsSeparatedByString(":") 
    let friOpen:[String] = json["OpeningHours"]["Friday"]["From"].string!.componentsSeparatedByString(":") 
    let friClose:[String] = json["OpeningHours"]["Friday"]["To"].string!.componentsSeparatedByString(":") 
    let satOpen:[String] = json["OpeningHours"]["Saturday"]["From"].string!.componentsSeparatedByString(":") 
    let satClose:[String] = json["OpeningHours"]["Saturday"]["To"].string!.componentsSeparatedByString(":") 
    let sunOpen:[String] = json["OpeningHours"]["Sunday"]["From"].string!.componentsSeparatedByString(":") 
    let sunClose:[String] = json["OpeningHours"]["Sunday"]["To"].string!.componentsSeparatedByString(":") 

Cách mẹ đẻ:

var monOpen:[String] = [] 
    var monClose:[String] = [] 
    var tueOpen:[String] = [] 
    var tueClose:[String] = [] 
    var wedOpen:[String] = [] 
    var wedClose:[String] = [] 
    var thuOpen:[String] = [] 
    var thuClose:[String] = [] 
    var friOpen:[String] = [] 
    var friClose:[String] = [] 
    var satOpen:[String] = [] 
    var satClose:[String] = [] 
    var sunOpen:[String] = [] 
    var sunClose:[String] = [] 
    var openDescription:String = "" 

    if let attractionsArray = orgJson as? NSArray{ 
     if let attraction = attractionsArray[0] as? NSDictionary{ 
      if let openHours = attraction["OpeningHours"] as? NSDictionary{ 
       if let day = openHours["Monday"] as? NSDictionary{ 
        if let open = day["From"] as? String{ 
         monOpen = open.componentsSeparatedByString(":") 
        } 
        if let close = day["To"] as? String{ 
         monClose = close.componentsSeparatedByString(":") 
        } 
       } 
       if let day = openHours["Tuesday"] as? NSDictionary{ 
        if let open = day["From"] as? String{ 
         tueOpen = open.componentsSeparatedByString(":") 
        } 
        if let close = day["To"] as? String{ 
         tueClose = close.componentsSeparatedByString(":") 
        } 
       } 
       if let day = openHours["Wednesday"] as? NSDictionary{ 
        if let open = day["From"] as? String{ 
         wedOpen = open.componentsSeparatedByString(":") 
        } 
        if let close = day["To"] as? String{ 
         wedClose = close.componentsSeparatedByString(":") 
        } 
       } 
       if let day = openHours["Thursday"] as? NSDictionary{ 
        if let open = day["From"] as? String{ 
         thuOpen = open.componentsSeparatedByString(":") 
        } 
        if let close = day["To"] as? String{ 
         thuClose = close.componentsSeparatedByString(":") 
        } 
       } 
       if let day = openHours["Friday"] as? NSDictionary{ 
        if let open = day["From"] as? String{ 
         friOpen = open.componentsSeparatedByString(":") 
        } 
        if let close = day["To"] as? String{ 
         friClose = close.componentsSeparatedByString(":") 
        } 
       } 
       if let day = openHours["Saturday"] as? NSDictionary{ 
        if let open = day["From"] as? String{ 
         satOpen = open.componentsSeparatedByString(":") 
        } 
        if let close = day["To"] as? String{ 
         satClose = close.componentsSeparatedByString(":") 
        } 
       } 
       if let day = openHours["Sunday"] as? NSDictionary{ 
        if let open = day["From"] as? String{ 
         sunOpen = open.componentsSeparatedByString(":") 
        } 
        if let close = day["To"] as? String{ 
         sunClose = close.componentsSeparatedByString(":") 
        } 
       } 
       if let desc = openHours["OpeningHoursGenericExceptions"] as? String{ 
        openDescription = desc 
       } 
      } 
     } 
    } 

Đây chỉ là một phần của dữ liệu được phân tích cú pháp để hiệu suất thực sự đáng chú ý trong ứng dụng.

Tôi đoán câu hỏi là, đã i sử dụng không đúng cách hoặc SwiftyJSON được này để được mong đợi?

Answer 1

Trước hết, "cách tự nhiên" của bạn không phải là tương đương với "Swifty cách".

Phiên bản SwiftyJSON có 45 subscript quyền truy cập, nhưng cách gốc chỉ có 23 subscript quyền truy cập.

Để thực hiện "cách bản địa" tương đương, nó phải là một cái gì đó như:

let openDescription = attraction["OpeningHours"]!["OpeningHoursGenericExceptions"] as String 
let monOpen = (attraction["OpeningHours"]!["Monday"]!!["From"] as String).componentsSeparatedByString(":") 
let monClose = (attraction["OpeningHours"]!["Monday"]!!["To"] as String).componentsSeparatedByString(":") 
let tueOpen = (attraction["OpeningHours"]!["Tuesday"]!!["From"] as String).componentsSeparatedByString(":") 
let tueClose = (attraction["OpeningHours"]!["Tuesday"]!!["To"]! as String).componentsSeparatedByString(":") 
// ... 

hoặc "Swifty cách" nên được như:

let openHours = json[0]["OpeningHours"] 
var day:JSON 

day = openHours["Monday"] 
if let open = day["From"].string { 
    monOpen = open.componentsSeparatedByString(":") 
} 
if let close = day["To"].string { 
    monClose = close.componentsSeparatedByString(":") 
} 
day = openHours["Tuesday"] 
if let open = day["From"].string { 
    tueOpen = open.componentsSeparatedByString(":") 
} 
if let close = day["To"].string { 
    tueClose = close.componentsSeparatedByString(":") 
} 
// ... 

---

Dù sao, Có, SwiftyJSON là chậm. Hãy đo:

import Foundation 
import XCTest 

let orgJson:AnyObject = [ 
    [ 
     "OpeningHours": [ 
      "OpeningHoursGenericExceptions": "test", 
      "Monday": ["From":"1:2:3","To":"1:2:3"], 
      "Tuesday": ["From":"1:2:3","To":"1:2:3"], 
      "Wednesday": ["From":"1:2:3","To":"1:2:3"], 
      "Thursday": ["From":"1:2:3","To":"1:2:3"], 
      "Friday": ["From":"1:2:3","To":"1:2:3"], 
      "Saturday": ["From":"1:2:3","To":"1:2:3"], 
      "Sunday": ["From":"1:2:3","To":"1:2:3"], 
     ] 
    ] 
] 
let json = JSON(orgJson) 

class JSONTestTests: XCTestCase { 

    func testNativeSubscript() { 
     measureBlock {() -> Void in 

      for _ in 0 ..< 400 { 
       autoreleasepool { 
        if let attraction = orgJson[0] as? NSDictionary { 
         let openDescription = attraction["OpeningHours"]!["OpeningHoursGenericExceptions"] as String 
         let monOpen = (attraction["OpeningHours"]!["Monday"]!!["From"] as String).componentsSeparatedByString(":") 
         let monClose = (attraction["OpeningHours"]!["Monday"]!!["To"] as String).componentsSeparatedByString(":") 
         let tueOpen = (attraction["OpeningHours"]!["Tuesday"]!!["From"] as String).componentsSeparatedByString(":") 
         let tueClose = (attraction["OpeningHours"]!["Tuesday"]!!["To"] as String).componentsSeparatedByString(":") 
         let wedOpen = (attraction["OpeningHours"]!["Wednesday"]!!["From"] as String).componentsSeparatedByString(":") 
         let wedClose = (attraction["OpeningHours"]!["Wednesday"]!!["To"] as String).componentsSeparatedByString(":") 
         let thuOpen = (attraction["OpeningHours"]!["Thursday"]!!["From"] as String).componentsSeparatedByString(":") 
         let thuClose = (attraction["OpeningHours"]!["Thursday"]!!["To"] as String).componentsSeparatedByString(":") 
         let friOpen = (attraction["OpeningHours"]!["Friday"]!!["From"] as String).componentsSeparatedByString(":") 
         let friClose = (attraction["OpeningHours"]!["Friday"]!!["To"] as String).componentsSeparatedByString(":") 
         let satOpen = (attraction["OpeningHours"]!["Saturday"]!!["From"] as String).componentsSeparatedByString(":") 
         let satClose = (attraction["OpeningHours"]!["Saturday"]!!["To"] as String).componentsSeparatedByString(":") 
         let sunOpen = (attraction["OpeningHours"]!["Sunday"]!!["From"] as String).componentsSeparatedByString(":") 
         let sunClose = (attraction["OpeningHours"]!["Sunday"]!!["To"] as String).componentsSeparatedByString(":") 
         XCTAssertEqual(monOpen, ["1","2","3"], "") 
         XCTAssertEqual(openDescription, "test") 
        } 
       } 
      } 
     } 
    } 

    func testJSONSubscript() { 
     measureBlock {() -> Void in 
      for _ in 0 ..< 400 { 
       autoreleasepool { 
        let attraction = json[0] 
        let openDescription:String = attraction["OpeningHours"]["OpeningHoursGenericExceptions"].string! 
        let monOpen:[String] = attraction["OpeningHours"]["Monday"]["From"].string!.componentsSeparatedByString(":") 
        let monClose:[String] = attraction["OpeningHours"]["Monday"]["To"].string!.componentsSeparatedByString(":") 
        let tueOpen:[String] = attraction["OpeningHours"]["Tuesday"]["From"].string!.componentsSeparatedByString(":") 
        let tueClose:[String] = attraction["OpeningHours"]["Tuesday"]["To"].string!.componentsSeparatedByString(":") 
        let wedOpen:[String] = attraction["OpeningHours"]["Wednesday"]["From"].string!.componentsSeparatedByString(":") 
        let wedClose:[String] = attraction["OpeningHours"]["Wednesday"]["To"].string!.componentsSeparatedByString(":") 
        let thuOpen:[String] = attraction["OpeningHours"]["Thursday"]["From"].string!.componentsSeparatedByString(":") 
        let thuClose:[String] = attraction["OpeningHours"]["Thursday"]["To"].string!.componentsSeparatedByString(":") 
        let friOpen:[String] = attraction["OpeningHours"]["Friday"]["From"].string!.componentsSeparatedByString(":") 
        let friClose:[String] = attraction["OpeningHours"]["Friday"]["To"].string!.componentsSeparatedByString(":") 
        let satOpen:[String] = attraction["OpeningHours"]["Saturday"]["From"].string!.componentsSeparatedByString(":") 
        let satClose:[String] = attraction["OpeningHours"]["Saturday"]["To"].string!.componentsSeparatedByString(":") 
        let sunOpen:[String] = attraction["OpeningHours"]["Sunday"]["From"].string!.componentsSeparatedByString(":") 
        let sunClose:[String] = attraction["OpeningHours"]["Sunday"]["To"].string!.componentsSeparatedByString(":") 
        XCTAssertEqual(monOpen, ["1","2","3"], "") 
       } 
      } 
     } 
    } 

    func testNativeBinding() { 
     measureBlock {() -> Void in 
      for _ in 0 ..< 400 { 
       autoreleasepool { 
        var monOpen:[String] = [] 
        var monClose:[String] = [] 
        var tueOpen:[String] = [] 
        var tueClose:[String] = [] 
        var wedOpen:[String] = [] 
        var wedClose:[String] = [] 
        var thuOpen:[String] = [] 
        var thuClose:[String] = [] 
        var friOpen:[String] = [] 
        var friClose:[String] = [] 
        var satOpen:[String] = [] 
        var satClose:[String] = [] 
        var sunOpen:[String] = [] 
        var sunClose:[String] = [] 
        var openDescription:String = "" 

        if let attractionsArray = orgJson as? NSArray{ 
         if let attraction = attractionsArray[0] as? NSDictionary{ 
          if let openHours = attraction["OpeningHours"] as? NSDictionary{ 
           if let day = openHours["Monday"] as? NSDictionary{ 
            if let open = day["From"] as? String{ 
             monOpen = open.componentsSeparatedByString(":") 
            } 
            if let close = day["To"] as? String{ 
             monClose = close.componentsSeparatedByString(":") 
            } 
           } 
           if let day = openHours["Tuesday"] as? NSDictionary{ 
            if let open = day["From"] as? String{ 
             tueOpen = open.componentsSeparatedByString(":") 
            } 
            if let close = day["To"] as? String{ 
             tueClose = close.componentsSeparatedByString(":") 
            } 
           } 
           if let day = openHours["Wednesday"] as? NSDictionary{ 
            if let open = day["From"] as? String{ 
             wedOpen = open.componentsSeparatedByString(":") 
            } 
            if let close = day["To"] as? String{ 
             wedClose = close.componentsSeparatedByString(":") 
            } 
           } 
           if let day = openHours["Thursday"] as? NSDictionary{ 
            if let open = day["From"] as? String{ 
             thuOpen = open.componentsSeparatedByString(":") 
            } 
            if let close = day["To"] as? String{ 
             thuClose = close.componentsSeparatedByString(":") 
            } 
           } 
           if let day = openHours["Friday"] as? NSDictionary{ 
            if let open = day["From"] as? String{ 
             friOpen = open.componentsSeparatedByString(":") 
            } 
            if let close = day["To"] as? String{ 
             friClose = close.componentsSeparatedByString(":") 
            } 
           } 
           if let day = openHours["Saturday"] as? NSDictionary{ 
            if let open = day["From"] as? String{ 
             satOpen = open.componentsSeparatedByString(":") 
            } 
            if let close = day["To"] as? String{ 
             satClose = close.componentsSeparatedByString(":") 
            } 
           } 
           if let day = openHours["Sunday"] as? NSDictionary{ 
            if let open = day["From"] as? String{ 
             sunOpen = open.componentsSeparatedByString(":") 
            } 
            if let close = day["To"] as? String{ 
             sunClose = close.componentsSeparatedByString(":") 
            } 
           } 
           if let desc = openHours["OpeningHoursGenericExceptions"] as? String{ 
            openDescription = desc 
           } 
          } 
         } 
        } 
        XCTAssertEqual(monOpen, ["1","2","3"], "") 
       } 
      } 
     } 
    } 
    func testJSONBinding() { 
     measureBlock {() -> Void in 
      for _ in 0 ..< 400 { 
       autoreleasepool { 
        var monOpen:[String] = [] 
        var monClose:[String] = [] 
        var tueOpen:[String] = [] 
        var tueClose:[String] = [] 
        var wedOpen:[String] = [] 
        var wedClose:[String] = [] 
        var thuOpen:[String] = [] 
        var thuClose:[String] = [] 
        var friOpen:[String] = [] 
        var friClose:[String] = [] 
        var satOpen:[String] = [] 
        var satClose:[String] = [] 
        var sunOpen:[String] = [] 
        var sunClose:[String] = [] 
        var openDescription:String = "" 

        let openHours = json[0]["OpeningHours"] 
        var day:JSON 

        day = openHours["Monday"] 
        if let open = day["From"].string { 
         monOpen = open.componentsSeparatedByString(":") 
        } 
        if let close = day["To"].string { 
         monClose 
          = close.componentsSeparatedByString(":") 
        } 
        day = openHours["Tuesday"] 
        if let open = day["From"].string { 
         tueOpen = open.componentsSeparatedByString(":") 
        } 
        if let close = day["To"].string { 
         tueClose = close.componentsSeparatedByString(":") 
        } 
        day = openHours["WednesDay"] 
        if let open = day["From"].string { 
         wedOpen = open.componentsSeparatedByString(":") 
        } 
        if let close = day["To"].string { 
         wedClose = close.componentsSeparatedByString(":") 
        } 
        day = openHours["Thursday"] 
        if let open = day["From"].string { 
         thuOpen = open.componentsSeparatedByString(":") 
        } 
        if let close = day["To"].string { 
         thuClose = close.componentsSeparatedByString(":") 
        } 
        day = openHours["Friday"] 
        if let open = day["From"].string { 
         friOpen = open.componentsSeparatedByString(":") 
        } 
        if let close = day["To"].string { 
         friClose = close.componentsSeparatedByString(":") 
        } 
        day = openHours["Saturday"] 
        if let open = day["From"].string { 
         satOpen = open.componentsSeparatedByString(":") 
        } 
        if let close = day["To"].string { 
         satClose = close.componentsSeparatedByString(":") 
        } 
        day = openHours["Sunday"] 
        if let open = day["From"].string { 
         sunOpen = open.componentsSeparatedByString(":") 
        } 
        if let close = day["To"].string { 
         sunClose = close.componentsSeparatedByString(":") 
        } 
        XCTAssertEqual(monOpen, ["1","2","3"], "") 
       } 
      } 
     } 
    } 

} 

Đầu ra:

<unknown>:0: Test Case '-[JSONTestTests.JSONTestTests testJSONBinding]' measured [Time, seconds] average: 0.804, relative standard deviation: 5.592%, values: [0.835687, 0.814827, 0.819685, 0.841900, 0.764961, 0.845202, 0.691442, 0.779255, 0.818213, 0.830698], performanceMetricID:com.apple.XCTPerformanceMetric_WallClockTime, baselineName: "", baselineAverage: , maxPercentRegression: 10.000%, maxPercentRelativeStandardDeviation: 10.000%, maxRegression: 0.100, maxStandardDeviation: 0.100 
<unknown>:0: Test Case '-[JSONTestTests.JSONTestTests testJSONSubscript]' measured [Time, seconds] average: 4.247, relative standard deviation: 3.496%, values: [4.019640, 4.004123, 4.146146, 4.194535, 4.487171, 4.300971, 4.310613, 4.408405, 4.318354, 4.279362], performanceMetricID:com.apple.XCTPerformanceMetric_WallClockTime, baselineName: "", baselineAverage: , maxPercentRegression: 10.000%, maxPercentRelativeStandardDeviation: 10.000%, maxRegression: 0.100, maxStandardDeviation: 0.100 
<unknown>:0: Test Case '-[JSONTestTests.JSONTestTests testNativeBinding]' measured [Time, seconds] average: 0.223, relative standard deviation: 2.773%, values: [0.221099, 0.227395, 0.218860, 0.225989, 0.227128, 0.222370, 0.229956, 0.214535, 0.210818, 0.229868], performanceMetricID:com.apple.XCTPerformanceMetric_WallClockTime, baselineName: "", baselineAverage: , maxPercentRegression: 10.000%, maxPercentRelativeStandardDeviation: 10.000%, maxRegression: 0.100, maxStandardDeviation: 0.100 
<unknown>:0: Test Case '-[JSONTestTests.JSONTestTests testNativeSubscript]' measured [Time, seconds] average: 0.362, relative standard deviation: 17.528%, values: [0.346285, 0.316185, 0.333650, 0.339416, 0.330243, 0.354034, 0.378730, 0.269519, 0.486904, 0.467607], performanceMetricID:com.apple.XCTPerformanceMetric_WallClockTime, baselineName: "", baselineAverage: , maxPercentRegression: 10.000%, maxPercentRelativeStandardDeviation: 10.000%, maxRegression: 0.100, maxStandardDeviation: 0.100 

• SwiftyJSON của bạn: 4,247
• bạn Quê quán: 0,223
• SwiftyJSON My: 0,804
• My Quê quán: 0,362

---

Bằng cách này, nếu tôi là bạn, tôi sẽ làm một cái gì đó như:

if let hours = orgJson[0]?["OpeningHours"] as? NSDictionary { 
    let openDescription = hours["OpeningHoursGenericExceptions"] as? String ?? "" 
    let monOpen = hours["Monday"]?["From"]??.componentsSeparatedByString?(":") as? [String] ?? [] 
    let monClose = hours["Monday"]?["To"]??.componentsSeparatedByString?(":") as? [String] ?? [] 
    let tueOpen = hours["Tuesday"]?["From"]??.componentsSeparatedByString?(":") as? [String] ?? [] 
    let tueClose = hours["Tuesday"]?["To"]??.componentsSeparatedByString?(":") as? [String] ?? [] 
    let wedOpen = hours["Wednesday"]?["From"]??.componentsSeparatedByString?(":") as? [String] ?? [] 
    let wedClose = hours["Wednesday"]?["To"]??.componentsSeparatedByString?(":") as? [String] ?? [] 
    let thuOpen = hours["Thursday"]?["From"]??.componentsSeparatedByString?(":") as? [String] ?? [] 
    let thuClose = hours["Thursday"]?["To"]??.componentsSeparatedByString?(":") as? [String] ?? [] 
    let friOpen = hours["Friday"]?["From"]??.componentsSeparatedByString?(":") as? [String] ?? [] 
    let friClose = hours["Friday"]?["To"]??.componentsSeparatedByString?(":") as? [String] ?? [] 
    let satOpen = hours["Saturday"]?["From"]??.componentsSeparatedByString?(":") as? [String] ?? [] 
    let satClose = hours["Saturday"]?["To"]??.componentsSeparatedByString?(":") as? [String] ?? [] 
    let sunOpen = hours["Sunday"]?["From"]??.componentsSeparatedByString?(":") as? [String] ?? [] 
    let sunClose = hours["Sunday"]?["To"]??.componentsSeparatedByString?(":") as? [String] ?? [] 

    // ... 
} 

Đó là lý nhanh chóng, an toàn, không quá phức tạp.

---

Tại sao SwiftyJSON chậm?

On subscript truy cập, SwiftyJSON làm:

1. kiểm tra chính là String
2. subscript lại với self[key:sub]
3. kiểm tra các đối tượng cơ bản là NSDictionary
4. subscript tiềm ẩn NSDictionary với phím
cung cấp
5. xây dựng JSON đối tượng với kết quả
6. return

lẽ trình biên dịch tối ưu hóa một số bước, nhưng "chậm hơn so với bản địa" có phần không thể tránh khỏi :)