Sending an HTTP POST request to an API using Swift

Using Swift
3

Simple example used in an async function to post JSON content from a message which is Codable:

      let url = URL(string: address)!
      var request = URLRequest(url: url)
      request.setValue("application/json", forHTTPHeaderField: "Content-Type")
      request.httpMethod = "POST"
      let encoder = JSONEncoder()
      let data = try encoder.encode(message)
      request.httpBody = data

      let (responseData, response) = try await URLSession.shared.upload(for: request, from: data, delegate: self)
      // etc...