如何在 swift 4 中使用 Graphql 获取 json 值数组？

Question

我正在使用 graphql 通过 Apollo 获取 API 值。我已成功下载 schema.json 并从 grpahql 获取值。但我无法获取 json 值的 values 数组。

这是我的示例回复：

 {
  "data": {
  "team_Dashboard": {
  "activeMission": "Food Mission",
  "currentMissionChallenges": [
   {
    "id": "123",
    "title": "Challenge",
    "estTime": "5",
    "location": "Anywhere",
    "maxPts": "30",
    "status": "Not yet started"
   },
   {
    "id": "1234",
    "title": " II Challenge",
    "estTime": "5",
    "location": "Anywhere",
    "maxPts": "70",
    "status": "Not yet started"
    }
   ]
  }
 }
}

Graphql 查询：

query teamDashboard($teamId: ID!) {
  team_Dashboard(teamId: $teamId) {
   activeMission
   currentMissionChallenges
 }
}

Graphql 架构响应：

missionDeadLine: String
currentMissionChallenges: [JSON]

当我在我的 Graphql 查询中添加 currentMissionChallenges([JSON]) 时，会从服务器获取错误响应。但是当我从 Graphql 查询中删除 currentMissionChallenges 时，会从服务器获取成功响应和值。

问题是 currentMissionChallenges 是 [JSON] 格式。当我更改我的 graphql 查询 This is graphql Response

 query teamDashboard($teamId: ID!) {
  team_Dashboard(teamId: $teamId) {
   activeMission
   currentMissionChallenges {
        id
        title
        estTime
        location
        maxPts
        status
    }
  }
}

dashBord.grpahql 中显示以下错误

Field "currentMissionChallenges" must not have a selection since type "[JSON]" has no subfields.

如何从 graphql 获取 json 数组值。获取 Json 值有什么问题？请帮帮我！

Answer 1

The best thing about GraphQL is we can use the query as model

因为响应与查询相同，所以我们可以将响应分配给查询类型的变量。

让我用一个例子来解释：-

假设如果我需要查询我的个人资料数据，

Profile.graphql

query MyProfile{
    player {
        me {
            id
            secret
            name
            email
            state
            country
            timezone
            picture
            pictureType
            audio
            rank
        }
    }
    countries{
        value
        viewValue
    }
}

一旦我们构建了应用程序，它就会在 API.swift 中创建 MyProfileQuery。在 viewController 中，我们可以使用如下响应 -

var myProfileData: MyProfileQuery.Data.Player.Me? // Declaring the valiable of player Type

ApolloClientManager.sharedInstance
                .fetchQuery(MyProfileQuery(), showLoader: true,
                            viewController: self) { (response) in // Fetching response using Apollo Client Manager
                if let allData = response {
                    if let profiledata = allData.player?.me {
                        self.myProfileData = profiledata // Assigning response into the variable declared
                        self.myEdittingProfileData = profiledata
                        self.updateUI()
                    }
                    if let countryData = allData.countries {
                        self.allCountrydata = countryData
                        self.getPickerDataForState(comppletion: {
                            self.openTimeZonePicker(completion: {
                                print("got timeZone Data")
                            })
                        })
                    }
                }

            }

现在我们可以使用对 myProfileData 变量的响应 如下-

现在我们可以访问我们在查询中提到的所有值，如下所示

print("player id is-          \(myProfileData?.id)")
print("player name is-        \(myProfileData?.name)")
print("player email is-       \(myProfileData?.email)")
print("player state is-       \(myProfileData?.state)")
print("player rank is-        \(myProfileData?.rank)")
print("player pictureType is- \(myProfileData?.pictureType)")

// player id is-          10
// player name is-        jordan
// player email is-       jordan@domain.com
// player state is-       Ohio
// player rank is-        101
// player pictureType is- custome
// 

希望对你有所帮助???

Answer 2

我建议你使用自定义标量。

import Apollo
public typealias JSON = [String: Any]

extension Dictionary: JSONDecodable {
public init(jsonValue value: JSONValue) throws {

    if let array = value as? NSArray {
        self.init()
        if var dict = self as? [String: JSONDecodable & JSONEncodable] {
            dict["data"] = array as! [[String: Any]]
            self = dict as! Dictionary<Key, Value>
            return
        }
    }

    guard let dictionary = value as? Dictionary else {

        throw JSONDecodingError.couldNotConvert(value: value, to: Dictionary.self)
    }
    self = dictionary
}

}

var currentMissionChallanges = [JSON]()
func getTeamDashboard(id:String) {
     let query = TeamDashboardQuery(id:id)
     apollo.fetch(query:query) { [weak self] result, error in 
          if let dashboards = result.data?.team_dashboard {
             if let array = dashboards!["currentMissionChallanges"] as? 
[JSON] {
self?.currentMissionChallanges = array
}
          }
     }
}