为啥以这种方式使用 Alamofire 时没有发现任何价值？

Posted 2023-02-24

【中文标题】为啥以这种方式使用 Alamofire 时没有发现任何价值？

【英文标题】：Why is there no value found when using Alamofire this way?为什么以这种方式使用 Alamofire 时没有发现任何价值？

【发布时间】：2019-04-10 15:03:01

【问题描述】：

我正在使用 Alamofire 在 Yummly.com 上进行呼叫，该呼叫应将包含多个食谱的数组发回给我。进行 API 调用时，一切正常。但是当我尝试将这些多重响应添加到一个值中时，这条消息会出现问题：

valueNotFound(Swift.Int, Swift.DecodingError.Context(codingPath: [CodingKeys(stringValue: "matches", intValue: nil), _JSONKey(stringValue: "Index 5", intValue: 5), CodingKeys(stringValue: " totalTimeInSeconds", intValue: nil)], debugDescription: "预期的 Int 值，但发现为 null。"，underlyingError: nil))

struct RecipeSearchResult: Decodable 
  let name: String?
  let ingredients: String?
  let image: URL?
  let rating: Int?
  let timer: Int?


struct SearchRecipesRoot: Decodable 
  let matches: [Matches]


struct Matches: Decodable 
  let recipeName: String
  let smallImageUrls: [URL]
  let ingredients: [String]
  let id: String
  let totalTimeInSeconds: Int
  let rating: Int


func searchRecipes(from userIngredients: String) 
    let urlSearchParameter = "&q=\(userIngredients)&requirePictures=true"
    let searchURL = URL(
      string: "https://api.yummly.com/v1/api/recipes?" + urlAPIParameter + urlSearchParameter)!

    Alamofire.request(searchURL, method: .get).responseJSON 
      (response) in
      guard response.result.isSuccess else 
        print("☠️ \(String(describing: response.result.error)) ☠️")
        return
      
      do 
        let responseJSON = try JSONDecoder().decode(SearchRecipesRoot.self, from: response.data!)
        for result in responseJSON.matches 
          let recipiesSearchResult = RecipeSearchResult(
            name: result.recipeName,
            ingredients: result.ingredients.joined(separator: "\n"),
            image: result.smallImageUrls[0],
            rating: result.rating,
            timer: result.totalTimeInSeconds
          )
          print(recipiesSearchResult)
        
      
      catch 
        print(error)
      
    
  

这是与找到的食谱一样重复的 JSON 响应：

    "criteria": 
        "q": "pasta tomatoes cheese salmon",
        "requirePictures": true,
        "allowedIngredient": null,
        "excludedIngredient": null
    ,
    "matches": [
        
            "imageUrlsBySize": 
                "90": "https://lh3.googleusercontent.com/7lLNUgFrzS0rHdWGYKhv4qnVg2mPkafkZzSqUWYrFCOJpV4xq_KwU5HuB8KGHdn40G-s-RQQISyaCyPdJWCxpA=s90-c"
            ,
            "sourceDisplayName": "The Washington Post",
            "ingredients": [
                "dried pasta",
                "olive oil",
                "vidalia onion",
                "garlic",
                "tomatoes",
                "cream cheese",
                "smoked salmon",
                "freshly ground black pepper",
                "basil leaves",
                "parmesan cheese"
            ],
            "id": "Tomato-and-Smoked-Salmon-Pasta-2161877",
            "smallImageUrls": [
                "https://lh3.googleusercontent.com/R1P8lKMQZz__M77Pav5ptnX2gdzxqY1wj6xzIaxHNuFFT6xe3QQ5E-nxgEROOJ2S0GUjpNruHrsNk-c0G9fO=s90"
            ],
            "recipeName": "Tomato and Smoked Salmon Pasta",
            "totalTimeInSeconds": 2100,
            "attributes": 
                "course": [
                    "Main Dishes"
                ]
            ,
            "flavors": 
                "piquant": 0,
                "meaty": 0.16666666666666666,
                "bitter": 0.3333333333333333,
                "sweet": 0.16666666666666666,
                "sour": 0.3333333333333333,
                "salty": 0.8333333333333334
            ,
            "rating": 3
        ,

【问题讨论】：

请edit您的问题包括您收到的 JSON 响应并导致错误。

您是否保证从 API 接收到 Matches 结构中的所有数据？如果没有，请将其设为可选。似乎您没有收到至少一个食谱的 totalTimeInSeconds。

【参考方案1】：

问题来自“计时器：result.totalTimeInSeconds”，它在某一时刻返回为零，这使得 API 调用返回“ValueNotFound”结果。

timer: result.totalTimeInSeconds ?? 0