`keyNotFound`在iOS上使用Swift从Gmail API响应创建对象时出错

我正在使用Alamofire通过消息ID从Gmail API获取电子邮件：

     AF.request("https://www.googleapis.com/gmail/v1/users/me/messages/\(id)?format=full", headers: headers)
            .responseJSON { [self] response in
                do {
                    let json = try JSON(data: response.data!)

                    if let rawString = json.rawString() {
                        let email = try Email(rawString)
                    } else {
                        print("json.rawString is nil")
                    }
                    emailFetchGroup.leave()
                }
                catch {
                    print(error)
                    emailFetchGroup.leave()
                }
            }

我有一个类，

Email

，我正试图通过JSON响应创建它：

// This file was generated from JSON Schema using quicktype, do not modify it directly.
// To parse the JSON, add this file to your project and do:
//
//   let email = try Email(json)

import Foundation

// MARK: - Email
class Email: Codable {
    let sizeEstimate: Int
    let historyID, threadID: String
    let payload: Payload
    let internalDate, snippet, id: String
    let labelIDS: [String]

    enum CodingKeys: String, CodingKey {
        case sizeEstimate
        case historyID = "historyId"
        case threadID = "threadId"
        case payload, internalDate, snippet, id
        case labelIDS = "labelIds"
    }

    init(sizeEstimate: Int, historyID: String, threadID: String, payload: Payload, internalDate: String, snippet: String, id: String, labelIDS: [String]) {
        self.sizeEstimate = sizeEstimate
        self.historyID = historyID
        self.threadID = threadID
        self.payload = payload
        self.internalDate = internalDate
        self.snippet = snippet
        self.id = id
        self.labelIDS = labelIDS
    }
}

// MARK: Email convenience initializers and mutators

extension Email {
    convenience init(data: Data) throws {
        let me = try newJSONDecoder().decode(Email.self, from: data)
        self.init(sizeEstimate: me.sizeEstimate, historyID: me.historyID, threadID: me.threadID, payload: me.payload, internalDate: me.internalDate, snippet: me.snippet, id: me.id, labelIDS: me.labelIDS)
    }

    convenience init(_ json: String, using encoding: String.Encoding = .utf8) throws {
        guard let data = json.data(using: encoding) else {
            throw NSError(domain: "JSONDecoding", code: 0, userInfo: nil)
        }
        try self.init(data: data)
    }

    convenience init(fromURL url: URL) throws {
        try self.init(data: try Data(contentsOf: url))
    }

    func with(
        sizeEstimate: Int? = nil,
        historyID: String? = nil,
        threadID: String? = nil,
        payload: Payload? = nil,
        internalDate: String? = nil,
        snippet: String? = nil,
        id: String? = nil,
        labelIDS: [String]? = nil
    ) -> Email {
        return Email(
            sizeEstimate: sizeEstimate ?? self.sizeEstimate,
            historyID: historyID ?? self.historyID,
            threadID: threadID ?? self.threadID,
            payload: payload ?? self.payload,
            internalDate: internalDate ?? self.internalDate,
            snippet: snippet ?? self.snippet,
            id: id ?? self.id,
            labelIDS: labelIDS ?? self.labelIDS
        )
    }

    func jsonData() throws -> Data {
        return try newJSONEncoder().encode(self)
    }

    func jsonString(encoding: String.Encoding = .utf8) throws -> String? {
        return String(data: try self.jsonData(), encoding: encoding)
    }
}

// MARK: - Payload
class Payload: Codable {
    let mimeType: String
    let headers: [Header]
    let body: Body
    let partID, filename: String

    enum CodingKeys: String, CodingKey {
        case mimeType, headers, body
        case partID = "partId"
        case filename
    }

    init(mimeType: String, headers: [Header], body: Body, partID: String, filename: String) {
        self.mimeType = mimeType
        self.headers = headers
        self.body = body
        self.partID = partID
        self.filename = filename
    }
}

// MARK: Payload convenience initializers and mutators

extension Payload {
    convenience init(data: Data) throws {
        let me = try newJSONDecoder().decode(Payload.self, from: data)
        self.init(mimeType: me.mimeType, headers: me.headers, body: me.body, partID: me.partID, filename: me.filename)
    }

    convenience init(_ json: String, using encoding: String.Encoding = .utf8) throws {
        guard let data = json.data(using: encoding) else {
            throw NSError(domain: "JSONDecoding", code: 0, userInfo: nil)
        }
        try self.init(data: data)
    }

    convenience init(fromURL url: URL) throws {
        try self.init(data: try Data(contentsOf: url))
    }

    func with(
        mimeType: String? = nil,
        headers: [Header]? = nil,
        body: Body? = nil,
        partID: String? = nil,
        filename: String? = nil
    ) -> Payload {
        return Payload(
            mimeType: mimeType ?? self.mimeType,
            headers: headers ?? self.headers,
            body: body ?? self.body,
            partID: partID ?? self.partID,
            filename: filename ?? self.filename
        )
    }

    func jsonData() throws -> Data {
        return try newJSONEncoder().encode(self)
    }

    func jsonString(encoding: String.Encoding = .utf8) throws -> String? {
        return String(data: try self.jsonData(), encoding: encoding)
    }
}

// MARK: - Body
class Body: Codable {
    let size: Int
    let attachmentID: String

    enum CodingKeys: String, CodingKey {
        case size
        case attachmentID = "attachmentId"
    }

    init(size: Int, attachmentID: String) {
        self.size = size
        self.attachmentID = attachmentID
    }
}

// MARK: Body convenience initializers and mutators

extension Body {
    convenience init(data: Data) throws {
        let me = try newJSONDecoder().decode(Body.self, from: data)
        self.init(size: me.size, attachmentID: me.attachmentID)
    }

    convenience init(_ json: String, using encoding: String.Encoding = .utf8) throws {
        guard let data = json.data(using: encoding) else {
            throw NSError(domain: "JSONDecoding", code: 0, userInfo: nil)
        }
        try self.init(data: data)
    }

    convenience init(fromURL url: URL) throws {
        try self.init(data: try Data(contentsOf: url))
    }

    func with(
        size: Int? = nil,
        attachmentID: String? = nil
    ) -> Body {
        return Body(
            size: size ?? self.size,
            attachmentID: attachmentID ?? self.attachmentID
        )
    }

    func jsonData() throws -> Data {
        return try newJSONEncoder().encode(self)
    }

    func jsonString(encoding: String.Encoding = .utf8) throws -> String? {
        return String(data: try self.jsonData(), encoding: encoding)
    }
}

// MARK: - Header
class Header: Codable {
    let name, value: String

    init(name: String, value: String) {
        self.name = name
        self.value = value
    }
}

// MARK: Header convenience initializers and mutators

extension Header {
    convenience init(data: Data) throws {
        let me = try newJSONDecoder().decode(Header.self, from: data)
        self.init(name: me.name, value: me.value)
    }

    convenience init(_ json: String, using encoding: String.Encoding = .utf8) throws {
        guard let data = json.data(using: encoding) else {
            throw NSError(domain: "JSONDecoding", code: 0, userInfo: nil)
        }
        try self.init(data: data)
    }

    convenience init(fromURL url: URL) throws {
        try self.init(data: try Data(contentsOf: url))
    }

    func with(
        name: String? = nil,
        value: String? = nil
    ) -> Header {
        return Header(
            name: name ?? self.name,
            value: value ?? self.value
        )
    }

    func jsonData() throws -> Data {
        return try newJSONEncoder().encode(self)
    }

    func jsonString(encoding: String.Encoding = .utf8) throws -> String? {
        return String(data: try self.jsonData(), encoding: encoding)
    }
}

// MARK: - Helper functions for creating encoders and decoders

func newJSONDecoder() -> JSONDecoder {
    let decoder = JSONDecoder()
    if #available(iOS 10.0, OSX 10.12, tvOS 10.0, watchOS 3.0, *) {
        decoder.dateDecodingStrategy = .iso8601
    }
    return decoder
}

func newJSONEncoder() -> JSONEncoder {
    let encoder = JSONEncoder()
    if #available(iOS 10.0, OSX 10.12, tvOS 10.0, watchOS 3.0, *) {
        encoder.dateEncodingStrategy = .iso8601
    }
    return encoder
}

这几乎是完美的；除了

attachmentID

参数之外-当我尝试创建电子邮件时，我收到以下错误：

keyNotFound(CodingKeys(stringValue: "attachmentId", intValue: nil), Swift.DecodingError.Context(codingPath: [CodingKeys(stringValue: "payload", intValue: nil), CodingKeys(stringValue: "body", intValue: nil)], debugDescription: "No value associated with key CodingKeys(stringValue: \"attachmentId\", intValue: nil) (\"attachmentId\").", underlyingError: nil))

在这件事上我有点不知所措；因此，感谢您的帮助-我需要做些什么来确保这一财产得到分配

编辑我忘记包含JSON响应；详情如下:

{
  "snippet" : "",
  "id" : "1758550e1d57a61e",
  "internalDate" : "1604259323000",
  "sizeEstimate" : 1811162,
  "threadId" : "1758549a183c08f0",
  "payload" : {
    "partId" : "",
    "mimeType" : "video\/mp4",
    "filename" : "nicholasarner@gmail.com-2020_11_01_11_35_23-WDYT?.mp4",
    "body" : {
      "size" : 1322930,
      "attachmentId" : "ANGjdJ_nEZvNaV972a1H9osO7Ze3WH-F5hlf8cSEQjgM9NmI8XzsKsfhAF_zV7addIHsIEgm8nmlPGID8pICD5ew8399hocuXwvfGVx_Pl3Z7f1jwgmrm1_UD6k1daGkaXFFy7kbfiiRRidy42IoKT9r3FoS4tb7mVmv7ctrQE9KvCjV2Op3MCkzvrjM494iG06yJtQhM5Zt697BG-kythaCjacFJ5cTh4c-qdCN60JIUL3sR95AWnoEvSBMVr_i6iPKIP67gpddw27MkMmqICA8jkJXXSGhGaZek2hJu886ik_3VCvqlQ4c2uypWVYNOfWMPvjVuNmlW-_MH41cSo_mqd2DaxBVkXut70bu24y2-aY50ljhVZRqhV6CSoUlbBiPEe_VxToATBy_vFLF8TZRlOGg5Jq0kleymZvRgg"
    },
    "headers" : [
      {
        "name" : "Return-Path",
        "value" : "<nicholasarner@gmail.com>"
      },
      {
        "name" : "Received",
        "value" : "from iPhone ([2601:645:4200:3950:441:1411:7e85:db6d])        by smtp.gmail.com with ESMTPSA id u124sm12113464pfc.21.2020.11.01.11.35.24        for <nicholasarner@gmail.com>        (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128\/128);        Sun, 01 Nov 2020 11:37:51 -0800 (PST)"
      },
      {
        "name" : "Date",
        "value" : "Sun, 1 Nov 2020 11:35:23 -0800"
      },
      {
        "name" : "From",
        "value" : "nicholasarner@gmail.com"
      },
      {
        "name" : "To",
        "value" : "Nick Arner <nicholasarner@gmail.com>"
      },
      {
        "name" : "Message-ID",
        "value" : "<d5ff6514-1c55-4d98-a4d3-43a776d7b05d@iPhone>"
      },
      {
        "name" : "In-Reply-To",
        "value" : "<CAD1H43XCrKQD3omFV2ggf_e2kLm_v4234p2oHvvKGd-bJ4PZeQ@mail.gmail.com>"
      },
      {
        "name" : "Subject",
        "value" : "Re: tett"
      },
      {
        "name" : "MIME-Version",
        "value" : "1.0"
      },
      {
        "name" : "Content-Type",
        "value" : "video\/mp4"
      },
      {
        "name" : "Content-Transfer-Encoding",
        "value" : "base64"
      },
      {
        "name" : "Content-Disposition",
        "value" : "attachment; filename=\"nicholasarner@gmail.com-2020_11_01_11_35_23-WDYT?.mp4\""
      }
    ]
  },
  "historyId" : "11441245",
  "labelIds" : [
    "IMPORTANT",
    "SENT",
    "INBOX"
  ]
}

{
“代码段”：“，
“id”：“1758550e1d57a61e”，
“内部日期”：“1604259323000”，
“sizeEstimate”：1811162，
“线程ID”：“1758549a183c08f0”，
“有效载荷”：{
“第三方”：“，
“mimeType”：“视频\/mp4”，
“文件名”：”nicholasarner@gmail.com-2020年11月01日11月35日23-WDYT？.mp4“，
“正文”：{
“大小”：1322930，
“附件”："在中国，一个中国的一个ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZmpvvunmlw-_MH41cSo_mqd2DaxBVkXut70bu24y2-AY50LJHVZRQHV6C管道VxToaby_vFLF8TZRlOGg5Jq0kleymZvRgg“
},
“标题”：[
{
“名称”：“返回路径”，
“值”：”
},
{
“姓名”：“已收到”，
“值”：“来自iPhone（[2601:645:4200:3950:441:1411:7e85:db6d]），由smtp.gmail.com提供，ESMTPSA id为u124sm12113464pfc.21.2020.11.01.11.35.24（版本=TLS1_2密码=ECDHE-ECDSA-AES128-GCM-SHA256位=128\/128）；Sun，2020年11月1日11:37:51-0800（太平洋标准时间）”
},
{
“姓名”：“日期”，
“价值”：“太阳，2020年11月1日11:35:23-0800”
},
{
“姓名”：“发件人”，
“值”：nicholasarner@gmail.com"
},
{
“姓名”：“收件人”，
“价值”：“尼克·阿纳”
},
{
“名称”：“消息ID”，
“值”：”
},
{
“姓名”：“回复”，
“值”：”
},
{
“名称”：“主题”，
“值”：“Re:tett”
},
{
“名称”：“MIME版本”，
“值”：“1.0”
},
{
“名称”：“内容类型”，
“值”：“视频\/mp4”
},
{
“名称”：“内容传输编码”，
“值”：“base64”
},
{
“名称”：“内容处置”，
“值”：“附件；文件名=\”nicholasarner@gmail.com-2020年11月01日11月35日23-WDYT？.mp4“
}
]
},
“历史ID”：“11441245”，
“labelIds”：[
“重要”，
“已发送”，
“收件箱”
]
}

错误清楚地表明，

body

JSON对象中没有键

attachmentId

，它在

payload

JSON对象中。您能在问题中包含您的原始JSON的有效示例吗？@gcharita是的，我的错误；我刚刚在问题中添加了JSON输出-谢谢！这不是原始JSON。请打印

json.rawString（）

并将其添加到您的问题中。@gcharita感谢您的耐心；刚刚添加了

rawString（）

output！除了您将响应从

Data

转换为

String

只是为了再次将其转换回

Data

进行解码之外，您的代码在我这端正确运行。