Asynchronous json retrieval

Question

Cotherstone OP

Created 3w

Replies 1

Boosts 0

Participants 2

Hello,

I am getting an error message "Cannot convert value of type 'URLSessionDataTask' to expected argument type 'Data'" for the last line of this code. Please can you tell me what the problem is? Thank you

 struct Item : Codable {
    var id: String
    var name: String
    var country: String
    var type: String
    var overallrecsit: String
    var dlastupd: String
    var doverallrecsit: String
}
 
    let url = URL(string:"https://www.TEST_URL.com/api_ios.php")
 
    let json = try? JSONDecoder().decode(Item.self, from: URLSession.shared.dataTask(with: url!))

Answered by darkpaw in 828158022

You're passing a data task into the method, rather than the data that it needs. The error message is quite explicit about that.

Try something like this:

 let url = URL(string: "https://www.TEST_URL.com/api_ios.php")!
let config = URLSessionConfiguration.default
config.requestCachePolicy = .reloadIgnoringLocalAndRemoteCacheData
 
let session = URLSession.init(configuration: config)
session.dataTask(with: url) {(data, response, error) in
  do {
    if let json = data {
      if let decodedData = try? JSONDecoder().decode(Item.self, from: json) {
...
      }
    }
  }
}.resume()

Boost

Answer 1

darkpaw OP

3w

Accepted Answer

You're passing a data task into the method, rather than the data that it needs. The error message is quite explicit about that.

Try something like this:

 let url = URL(string: "https://www.TEST_URL.com/api_ios.php")!
let config = URLSessionConfiguration.default
config.requestCachePolicy = .reloadIgnoringLocalAndRemoteCacheData
 
let session = URLSession.init(configuration: config)
session.dataTask(with: url) {(data, response, error) in
  do {
    if let json = data {
      if let decodedData = try? JSONDecoder().decode(Item.self, from: json) {
...
      }
    }
  }
}.resume()

0

	struct Item : Codable {
	var id: String
	var name: String
	var country: String
	var type: String
	var overallrecsit: String
	var dlastupd: String
	var doverallrecsit: String
	}

	let url = URL(string:"https://www.TEST_URL.com/api_ios.php")

	let json = try? JSONDecoder().decode(Item.self, from: URLSession.shared.dataTask(with: url!))

	let url = URL(string: "https://www.TEST_URL.com/api_ios.php")!
	let config = URLSessionConfiguration.default
	config.requestCachePolicy = .reloadIgnoringLocalAndRemoteCacheData

	let session = URLSession.init(configuration: config)
	session.dataTask(with: url) {(data, response, error) in
	do {
	if let json = data {
	if let decodedData = try? JSONDecoder().decode(Item.self, from: json) {
	...
	}
	}
	}
	}.resume()