how to deserialize a collection from an alamofire request - swift

Question

this is a pretty basic question of the syntax for deserializing responsejson collection in alamofire and swift
I have a GET service that returns an array of user objects e.g.
[
{"uname": "bob"},
{"uname": "jane"}
]
and here is my request
Alamofire.request(.GET, url , encoding:.JSON)
.responseJSON(options: .MutableContainers, completionHandler:{ (request, response, JSON, error) -> Void in
let result = JSON as? [Dictionary<String,String>]
if (response!.statusCode == 200 && error == nil){
//how should I deserialize the result here to return [String]
callback(success: true, errorMsg: nil, friends:friends)
}
else{
callback(success: false,errorMsg:error?.localizedDescription,friends:nil)
}
})
My question is how to deserialize the result, and am I correct to assume that the json result is a [Dictionary] and in order for me to change it to a [String] result, should I map it?
If I use the map syntax below I have a few questions
let friends = result?.map {
return $0["uname"] as String?
}
With the optional return value can I get it to return a [String] instead of a [String?] in a graceful way - isn't there a way to let map return only non null values somehow in a concise syntax?
Also is there a better syntax for map that lets me name the parameters instead of using $0?

Answer 1

I use Alamofire with SwiftyJSON to do the job and deserialise array of JSON objects to native objects. Here is an example of how I do it:
Alamofire.request(request)
.responseJSON(options: nil) { (request, response, json, error) -> Void in
if let requestError = error as NSError?{
callback!(nil, nil, requestError)
}
if let httpResponse = response as NSHTTPURLResponse?{
if(httpResponse.statusCode != 200){
callback!(nil, httpResponse, nil)
} else{
let jsonResult = JSON(json!) as JSON
var concerts = self.deserializeConcerts(jsonResult)
callback!(concerts, nil, nil)
}
}
}
Deserialize concerts looks like this:
class private func deserializeConcerts(concerts: SwiftyJSON.JSON) -> [ConcertModel]{
let concertsArray = concerts.object as! NSMutableArray
var concertObjs = [ConcertModel]()
for concert in concertsArray{
let concertObj = ConcertModel(concert: concert as! NSDictionary)
concertObjs.append(concertObj)
}
return concertObjs
}
And finally, ConcertModel initialiser just maps the values of the NSDictionary to the properties of the ConcertModel object.

Answer 2

Updated implementation for Alamofire 4.3
Alamofire.request(url, method: .get)
.responseJSON { response in
if response.data != nil {
let json = JSON(data: response.data!)
let name = json["data"][0]["name"].string
if name != nil {
print(name!)
}
}
}
That will parse this JSON input:
{
data: [
{ name: 'John' },
{ name: 'Dave' }
]
}