Well, my question is simple. I want to do the same as this answer but for encode: How to decode a property with type of JSON dictionary in Swift 4 decodable protocol
That solution works fine with decode, but I also need encode a Dictionary<String, Any>
I can't realize how to write the extension for KeyedEncodingContainer and the other extensions, and what methods to write.
You can do that by adapting the Decodable code snippet from that question's answer
extension KeyedEncodingContainerProtocol where Key == JSONCodingKeys {
mutating func encodeJSONDictionary(_ value: Dictionary<String, Any>) throws {
try value.forEach({ (key, value) in
let key = JSONCodingKeys(key: key)
switch value {
case let value as Bool:
try encode(value, forKey: key)
case let value as Int:
try encode(value, forKey: key)
case let value as String:
try encode(value, forKey: key)
case let value as Double:
try encode(value, forKey: key)
case let value as Dictionary<String, Any>:
try encode(value, forKey: key)
case let value as Array<Any>:
try encode(value, forKey: key)
case Optional<Any>.none:
try encodeNil(forKey: key)
default:
throw EncodingError.invalidValue(value, EncodingError.Context(codingPath: codingPath + [key], debugDescription: "Invalid JSON value"))
}
})
}
}
extension KeyedEncodingContainerProtocol {
mutating func encode(_ value: Dictionary<String, Any>, forKey key: Key) throws {
var container = self.nestedContainer(keyedBy: JSONCodingKeys.self, forKey: key)
try container.encodeJSONDictionary(value)
}
mutating func encodeIfPresent(_ value: Dictionary<String, Any>?, forKey key: Key) throws {
if let value = value {
try encode(value, forKey: key)
}
}
mutating func encode(_ value: Array<Any>, forKey key: Key) throws {
var container = self.nestedUnkeyedContainer(forKey: key)
try container.encodeJSONArray(value)
}
mutating func encodeIfPresent(_ value: Array<Any>?, forKey key: Key) throws {
if let value = value {
try encode(value, forKey: key)
}
}
}
extension UnkeyedEncodingContainer {
mutating func encodeJSONArray(_ value: Array<Any>) throws {
try value.enumerated().forEach({ (index, value) in
switch value {
case let value as Bool:
try encode(value)
case let value as Int:
try encode(value)
case let value as String:
try encode(value)
case let value as Double:
try encode(value)
case let value as Dictionary<String, Any>:
try encode(value)
case let value as Array<Any>:
try encode(value)
case Optional<Any>.none:
try encodeNil()
default:
let keys = JSONCodingKeys(intValue: index).map({ [ $0 ] }) ?? []
throw EncodingError.invalidValue(value, EncodingError.Context(codingPath: codingPath + keys, debugDescription: "Invalid JSON value"))
}
})
}
mutating func encodeJSONDictionary(_ value: Dictionary<String, Any>) throws {
var nestedContainer = self.nestedContainer(keyedBy: JSONCodingKeys.self)
try nestedContainer.encodeJSONDictionary(value)
}
}
Here's a code snippet for that
However, this code snippet will fail in Swift 4.1 which should be released within the first half of 2018.
