JSON data couldn’t be read

Question

I am trying to replicate following GET request in my project:

curl -XGET 'https://api2.branch.io/v1/url?url=https://example.app.link/WgiqvsepqF&branch_key=key_live_kaFuWw8WvY7yn1d9yYiP8gokwqjV0Swt'

Here is my final code:

if let url = URL(string: "https://example.app.link/WgiqvsepqF&branch_key=key_live_kaFuWw8WvY7yn1d9yYiP8gokwqjV0Swt"){
            let urlRequest = URLRequest(url: url)
            URLSession.shared.dataTask(with: urlRequest) { (data, response, error) in
                if error == nil{
                    do{
                        if let dataReceived = data, let jsonData = try JSONSerialization.jsonObject(with: dataReceived, options: .mutableLeaves) as? [String : Any]{
                            print(jsonData)
                        }
                    } catch let error{
                        print(error.localizedDescription)
                    }
                }
                }.resume()
        }

I am getting following error:

The data couldn’t be read because it isn’t in the correct format.

I tried other Stackoverflow and Reddit solution but nothing seems to be working.

Answer 1

API call is returning data keys in wrong format. You are receiving the keys starting from '$' or '~' e.g. '$og_title', '~stage'. That's why it's showing you an error.

• You can use Codable to parse the API. For that first, you need to make a Model struct for your API Call.
• Change the variable names according to Swift Syntax. I've replaced '$' with 'l' and '~' with 'i'. You can customize the code according to your needs.

This is your API Call

let url = URL(string: "https://api2.branch.io/v1/url?url=https://example.app.link/WgiqvsepqF&branch_key=key_live_kaFuWw8WvY7yn1d9yYiP8gokwqjV0Swt")
let request = NSMutableURLRequest(url: url!)
request.httpMethod = "GET"

let session = URLSession.shared
let task = session.dataTask(with: request as URLRequest, completionHandler: { (data, response, error) in
    guard ((data) != nil), let _: URLResponse = response, error == nil else {
        print("error")
        return
    }
    if let dataString = NSString(data: data!, encoding: String.Encoding.utf8.rawValue) {
        print(dataString)
        do {
            //here dataResponse received from a network request
            let decoder = JSONDecoder()
            let model = try decoder.decode(ResponseData.self, from: data!) //Decode JSON Response Data
            // Access your json data from Swift Structs e.g. model.type
            print(model.data?.iurl)
        } catch let parsingError {
            print("Error", parsingError)
        }
    }
})
task.resume()

This is your Model Struct

struct ResponseData : Codable {

    let data : MyData?
    let type : Int?
    let tags : [String]?
    let campaign : String?
    let feature : String?
    let channel : String?
    let stage : String?

    enum CodingKeys: String, CodingKey {

        case data = "data"
        case type = "type"
        case tags = "tags"
        case campaign = "campaign"
        case feature = "feature"
        case channel = "channel"
        case stage = "stage"
    }            
}

struct MyData : Codable {
    let custom_array : [Int]?
    let log_title : String?
    let custom_boolean : Bool?
    let custom_integer : Int?
    let icreation_source : Int?
    let log_description : String?
    let log_image_url : String?
    let istage : String?
    let custom_string : String?
    let ifeature : String?
    let url : String?
    let custom_object : Custom_object?
    let iurl : String?
    let ldesktop_url : String?
    let itags : [String]?
    let lcanonical_identifier : String?
    let lone_time_use : Bool?
    let iid : String?
    let icampaign : String?
    let ichannel : String?

    enum CodingKeys: String, CodingKey {

        case custom_array = "custom_array"
        case log_title = "$og_title"
        case custom_boolean = "custom_boolean"
        case custom_integer = "custom_integer"
        case icreation_source = "~creation_source"
        case log_description = "$og_description"
        case log_image_url = "$og_image_url"
        case istage = "~stage"
        case custom_string = "custom_string"
        case ifeature = "~feature"
        case url = "url"
        case custom_object = "custom_object"
        case iurl = "+url"
        case ldesktop_url = "$desktop_url"
        case itags = "~tags"
        case lcanonical_identifier = "$canonical_identifier"
        case lone_time_use = "$one_time_use"
        case iid = "~id"
        case icampaign = "~campaign"
        case ichannel = "~channel"
    }

}

struct Custom_object : Codable {
    let random : String?

    enum CodingKeys: String, CodingKey {

        case random = "random"
    }

}

Answer 2

The decoding code is correct.

The link is wrong, it should be https://api2.branch.io/v1/url?url=https://example.app.link/WgiqvsepqF&branch_key=key_live_kaFuWw8WvY7yn1d9yYiP8gokwqjV0Swt and not https://example.app.link/WgiqvsepqF&branch_key=key_live_kaFuWw8WvY7yn1d9yYiP8gokwqjV0Swt

Only decoding:

import UIKit

var json = """
{

    "data": {
        "custom_array": [
            1,
            2,
            3,
            4,
            5,
            6
        ],
        "$og_title": "Title from Deep Link",
        "custom_boolean": true,
        "custom_integer": 1243,
        "~creation_source": 0,
        "$og_description": "Description from Deep Link",
        "$og_image_url": "http://www.lorempixel.com/400/400/",
        "~stage": "new user",
        "custom_string": "everything",
        "~feature": "onboarding",
        "url": "https://example.app.link/WgiqvsepqF",
        "custom_object": {
            "random": "dictionary"
        },
        "+url": "https://example.app.link/WgiqvsepqF",
        "$desktop_url": "http://www.example.com",
        "~tags": [
            "one",
            "two",
            "three"
        ],
        "$canonical_identifier": "content/123",
        "$one_time_use": false,
        "~id": "423196192848102356",
        "~campaign": "new product",
        "~channel": "facebook"
    },
    "type": 0,
    "tags": [
        "one",
        "two",
        "three"
    ],
    "campaign": "new product",
    "feature": "onboarding",
    "channel": "facebook",
    "stage": "new user"

}
"""

let data = json.data(using: .utf8)!
do {
  if let jsonData = try JSONSerialization.jsonObject(with: data, options: .mutableLeaves) as? [String : Any] {
    print(jsonData)
}
} catch let error {
  print(error)
}