Swift String escaping when serializing to JSON using Codable - ios

Question

I'm trying to serialize my object as following:
import Foundation
struct User: Codable {
let username: String
let profileURL: String
}
let user = User(username: "John", profileURL: "http://google.com")
let json = try? JSONEncoder().encode(user)
if let data = json, let str = String(data: data, encoding: .utf8) {
print(str)
}
However on macOS I'm getting the following:
{"profileURL":"http:\/\/google.com","username":"John"}
(note escaped '/' character).
While on Linux machines I'm getting:
{"username":"John","profileURL":"http://google.com"}
How can I make JSONEncoder return the unescaped?
I need the string in JSON to be strictly unescaped.

Answer 1

For iOS 13+ / macOS 10.15+
You can use .withoutEscapingSlashes option to json decoder to avoid escaping slashes
let user = User(username: "John", profileURL: "http://google.com")
let jsonEncoder = JSONEncoder()
jsonEncoder.outputFormatting = .withoutEscapingSlashes
let json = try? jsonEncoder.encode(user)
if let data = json, let str = String(data: data, encoding: .utf8) {
print(str)
}
Console O/P
{"profileURL":"http://google.com","username":"John"}
NOTE: As mention by Martin R in comments \/ is a valid JSON escape sequence.

Answer 2

I ended up using replacingOccurrences(of:with:), which may not be the best solution, but it resolves the issue:
import Foundation
struct User: Codable {
let username: String
let profileURL: String
}
let user = User(username: "John", profileURL: "http://google.com")
let json = try? JSONEncoder().encode(user)
if let data = json, let str = String(data: data, encoding: .utf8)?.replacingOccurrences(of: "\\/", with: "/") {
print(str)
dump(str)
}

Answer 3

I got it. The thing was that it didn't contain any \ character. It is just the property of swift that it will always return such a string on a console. The workaround is to j-son parse it.
Still, you can be used below solution of replacing '\/' with "/" string
let newString = str.replacingOccurrences(of: "\\/", with: "/")
print(newString)

Answer 4

While playing around JSONEncoder/JSONDecoder,
I found that the URL type is lossy on encode -> decode.
Initializes with a string, relative to another URL.
init?(string: String, relativeTo: URL?)
Might be help this apple document: https://developer.apple.com/documentation/foundation/url
using the PropertyList version, however:
let url = URL(string: "../", relativeTo: URL(string: "http://google.com"))!
let url2 = PropertyListDecoder().decode([URL].self, from: PropertyListEncoder().encode([User]))
Other way
let url = URL(string: "../", relativeTo: URL(string: "http://google.com"))!
let url2 = JSONDecoder().decode([URL].self, from: JSONEncoder().encode([User]))
Hope will helpful to you!!

Answer 5

Actually you cannot do that since in macOS and Linux are a bit different escaping systems. On linux // is allowed, macOS - not(it uses NSSerialization). So, you can just add percent encoding on your string, which guarantees you equal strings on macOS and linux, right string posting to a server and right validating. On adding percent escaping set CharacterSet.urlHostAllowed. Could be done like this:
init(name: String, profile: String){
username = name
if let percentedString = profile.addingPercentEncoding(withAllowedCharacters: CharacterSet.urlHostAllowed){
profileURL = percentedString
}else{
profileURL = ""
}
}
In the same manner, you can removePercentEncoding
AND YOU DONT NEED MODIFY SERVER SIDE!!!