Given that, per his description, “metadata” can be anything, creating a struct
doesn’t really help.
Jon Shier
> On Jun 18, 2017, at 9:00 PM, somu subscribe <somu.subscr...@gmail.com> wrote:
>
> Create a struct for Metadata and conform to Coding
>
> Code:
>
> let string = """
> {
> "id": "4yq6txdpfadhbaqnwp3",
> "email": "john....@example.com <mailto:john....@example.com>",
> "name":"John Doe",
> "metadata": {
> "link_id": "linked-id",
> "buy_count": 4
> }
> }
> """
>
> let data = string.data(using: .utf8)! //Force unwrapping just for ease of
> explanation, use guard instead
>
> struct User: Codable {
>
> //Struct to handle the nested JSON
> struct Metadata : Codable {
> var linkID : String
> var buyCount : Int
>
> //Customisation, if you want if you want your properties to be
> different from the JSON key
> private enum CodingKeys : String, CodingKey {
> case linkID = "link_id"
> case buyCount = "buy_count"
> }
> }
>
> var id: String
> var email : String
> var name : String
> var metadata : Metadata
> }
>
> let decoder = JSONDecoder()
>
> do {
> let user = try decoder.decode(User.self, from: data)
> print(user)
> }
> catch {
> print("error:\(error)")
> }
>
> Reference:
>
> https://developer.apple.com/videos/play/wwdc2017/212/
> <https://developer.apple.com/videos/play/wwdc2017/212/>
>
>
> Regards,
> Muthu
>
>
>
>> On 19 Jun 2017, at 3:29 AM, Jon Shier via swift-users <swift-users@swift.org
>> <mailto:swift-users@swift.org>> wrote:
>>
>> The more I use Codable, the less suited to networking it becomes. In
>> reading a variety of blog posts about implementing custom Decodable support
>> from JSON, I kept running across the same pattern. Basically, users had
>> started implementing their own decoding protocols which wrap Decodable
>> types, and have a type that represents the JSON representation and then
>> their real type, with an initializer connecting the two. But apparently this
>> is Apple’s official solution, which is rather terrible since it would be
>> completely unnecessary if the Decodable APIs were more flexible or we could
>> access keys by key path rather than nesting full containers. I can’t image
>> how much code I would have to add to decode the nasty JSON APIs I’ve used
>> Argo to parse before. Every type would need an underlying raw representation
>> that, at the very least, would need custom keys, lest I pollute even those
>> models with the terrible keys the JSON actually has. Not to mention the
>> various transforms I needed. Once I hit any reasonably complex API, Argo is
>> far far simpler to implement in fewer lines of code.
>> In trying to make Argo’s JSON enum Decodable itself, I can’t seem to
>> find a way to access the Any representation of the raw JSON. In fact, it
>> appears there’s no way to represent an Any value in Codable at all, which
>> makes Codable rather useless for the scenarios like the one that prompted
>> this thread. Without such an ability it’s impossible to actually use Codable
>> with all of the JSON out there, where other solutions work just fine. Argo’s
>> JSON type is decodable by Argo, so you can use it to represent a blob of
>> JSON just fine. Other existing JSON frameworks have similar solutions.
>>
>>
>>
>> Jon
>>
>>> On Jun 18, 2017, at 3:21 AM, Rien via swift-users <swift-users@swift.org
>>> <mailto:swift-users@swift.org>> wrote:
>>>
>>> Dang, hit send too soon. Sorry.
>>>
>>> This does not address your question, so please ignore… (foot in mouth)!
>>>
>>> Regards,
>>> Rien
>>>
>>> Site: http://balancingrock.nl <http://balancingrock.nl/>
>>> Blog: http://swiftrien.blogspot.com <http://swiftrien.blogspot.com/>
>>> Github: http://github.com/Balancingrock <http://github.com/Balancingrock>
>>> Project: http://swiftfire.nl <http://swiftfire.nl/> - An HTTP(S) web server
>>> framework in Swift
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>> On 18 Jun 2017, at 09:19, Rien <r...@balancingrock.nl
>>>> <mailto:r...@balancingrock.nl>> wrote:
>>>>
>>>> Are you looking for a general purpose JSON interpreter / API ?
>>>>
>>>> There are many of them around, and in fact I do have my own:
>>>> https://github.com/Balancingrock/VJson
>>>> <https://github.com/Balancingrock/VJson>
>>>>
>>>> With VJson I would write:
>>>>
>>>> let json = VJson.parse(… your json object…)
>>>>
>>>> and then access the metadata as:
>>>>
>>>> let buyCount = (json | ”metadata” | ”buy_count”)?.intValue
>>>>
>>>> or:
>>>>
>>>> var buyCount: Int &= json | “metadata” | “buy_count”
>>>>
>>>> To loop over the content of metadata:
>>>>
>>>> for item in (json | “metadata”) ?? [ ] {
>>>> print (item.nameValue)
>>>> switch item.type {
>>>> case .object: …
>>>> case .number: …
>>>> case .string: …
>>>> etc...
>>>> }
>>>> }
>>>>
>>>> Obviously I am plugging my own code here, but there are many others
>>>> around, I understand that SwiftyJSON is quite popular but I have not used
>>>> that myself.
>>>>
>>>> Regards,
>>>> Rien
>>>>
>>>> Site: http://balancingrock.nl <http://balancingrock.nl/>
>>>> Blog: http://swiftrien.blogspot.com <http://swiftrien.blogspot.com/>
>>>> Github: http://github.com/Balancingrock <http://github.com/Balancingrock>
>>>> Project: http://swiftfire.nl <http://swiftfire.nl/> - An HTTP(S) web
>>>> server framework in Swift
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>> On 18 Jun 2017, at 04:07, Chris Anderson via swift-users
>>>>> <swift-users@swift.org <mailto:swift-users@swift.org>> wrote:
>>>>>
>>>>> Say I have a JSON object such as:
>>>>>
>>>>> {
>>>>> "id": "4yq6txdpfadhbaqnwp3",
>>>>> "email": "john....@example.com <mailto:john....@example.com>",
>>>>> "name":"John Doe",
>>>>> "metadata": {
>>>>> "link_id": "linked-id",
>>>>> "buy_count": 4
>>>>> }
>>>>> }
>>>>>
>>>>> And with a struct of:
>>>>>
>>>>> struct User: Codable {
>>>>> var id: String
>>>>> var email: String
>>>>> var name: String
>>>>> }
>>>>>
>>>>> How can I decode the `metadata` field into a Dictionary?
>>>>>
>>>>> I’ve tried doing things such as, in my struct,
>>>>>
>>>>> var metadata: Dictionary
>>>>>
>>>>> or
>>>>>
>>>>> var metadata: [String: Any]
>>>>>
>>>>> But I get the error
>>>>>
>>>>> MyPlayground.playground:3:7: note: cannot automatically synthesize
>>>>> 'Encodable' because '<<error type>>' does not conform to 'Encodable'
>>>>> var metadata: Dictionary
>>>>>
>>>>> A meta or metadata field on many APIs (such as www.stripe.com
>>>>> <http://www.stripe.com/>) can contain whatever you want, and I still want
>>>>> to be able to process it on the Swift end. How can I store that meta data
>>>>> field into a Dictionary that I can parse apart manually after?
>>>>>
>>>>> Thanks!
>>>>>
>>>>> Chris Anderson
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> _______________________________________________
>>>>> swift-users mailing list
>>>>> swift-users@swift.org <mailto:swift-users@swift.org>
>>>>> https://lists.swift.org/mailman/listinfo/swift-users
>>>>
>>>
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>>> swift-users@swift.org <mailto:swift-users@swift.org>
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>>
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