ObjectMapper + Firebase?

[Dodig]

Hi
How I can use ObjectMapper with Firebase?
Do you have any tutorials or samples?

[tristanhimmelman]

Sorry I have never used or heard of Firebase so I do not have any samples to tutorials for you.

[Dodig]

@tristanhimmelman if you don't know Firebase you can check this: Firebase features :wink:

Firebase Realtime Database
Data in your Firebase database is stored as JSON and synchronized in realtime to every connected client. When you build cross-platform apps with our Android, iOS, and JavaScript SDKs, all of your clients share one Firebase database and automatically receive updates with the newest data.

With Firebase we manage NSDictionary and NSArray that I need to map to internal classes.
Can I use ObjectMapper for that?

[fractalzombie]

I'm interesting the same thing.

[TofPlay]

Found it! 😀

Example with an Array of users

Json

Import this Json at https://<your db>.firebaseio.com/Users
Replace <your db> by your database

{
  "Users": [
    {
      "firstName": "Paul",
      "lastName": "Dumont"
    },
    {
      "firstName": "Jacque",
      "lastName": "Zero"
    },
    {
      "firstName": "Marc",
      "lastName": "Longshot"
    }
  ]
}

ObjectMapper class

import Foundation
import ObjectMapper

class User: Mappable {

  var firstName:String? = nil
  var lastName:String? = nil

  required init?(_ pMap: Map){
  }

  func mapping(pMap: Map) {
    self.firstName  <- pMap["firstName"]
    self.lastName   <- pMap["lastName"]
  }
}

View Controller

Replace <your db> by your database name

import UIKit
import Firebase
import ObjectMapper

class FirebaseViewController: UIViewController {

  override func viewDidLoad() {
      super.viewDidLoad()

      let lUsers = Firebase(url: "https://<your db>.firebaseio.com/Users")

      lUsers.observeEventType(.Value) {
        (pSnapshot:FDataSnapshot!) -> Void in

        if let lJsonArray = pSnapshot.value as? [[String : AnyObject]] {
          let lUsers = Mapper<User>().mapArray(lJsonArray)
          print("\(lUsers)")
        }
      }
   }
}

Debug view

[Dodig]

Thanks :smile:

[omarzl]

Maybe this is helpful to someone, I ended up creating a mix of many resources on the Internet.
This is the base class:

`
import UIKit
import Firebase

class FIRDataObject: NSObject {

var snapshot: FIRDataSnapshot!
var key: String { return snapshot.key }
var ref: FIRDatabaseReference { return snapshot.ref }

required init(_ snapshot: FIRDataSnapshot) {
    super.init()
    self.snapshot = snapshot
    for child in snapshot.children {
        if respondsToSelector(Selector(child.key)) {
            setValue(child.value, forKey: child.key)
        }
    }
    load()
}

func load(){

    // retrieve the properties via the class_copyPropertyList function
    var count: UInt32 = 0;
    let myClass: AnyClass = self.classForCoder;
    let properties = class_copyPropertyList(myClass, &count)

    // iterate each objc_property_t struct
    for i:UInt32 in 0..<count{
        let property = properties[Int(i)]

        // retrieve the property name by calling property_getName function
        let cname = property_getName(property)

        // covert the c string into a Swift string
        if let name = String.fromCString(cname){
            if let value=snapshot.value!.valueForKey(name){
                self.setValue(value, forKey: name)
            }
        }
    }
    // release objc_property_t structs
    free(properties);
}

func save(){
    var dicc=[String:AnyObject]()

    // retrieve the properties via the class_copyPropertyList function
    var count: UInt32 = 0;
    let myClass: AnyClass = self.classForCoder;
    let properties = class_copyPropertyList(myClass, &count)

    // iterate each objc_property_t struct
    for i:UInt32 in 0..<count{
        let property = properties[Int(i)]

        // retrieve the property name by calling property_getName function
        let cname = property_getName(property)

        // covert the c string into a Swift string
        if let name = String.fromCString(cname){

            let value=self.valueForKey(name)
            dicc[name]=value
        }
    }
    ref.setValue(dicc)

    // release objc_property_t structs
    free(properties);
}

}
protocol FIRDatabaseReferenceable {
var ref: FIRDatabaseReference { get }
}
extension FIRDatabaseReferenceable {
var ref: FIRDatabaseReference {
return FIRDatabase.database().reference()
}
}
`

you only need to inherit from it:

`
class User: FIRDataObject {

var name=""
var username=""
var amigos=[String:Bool]()

}
`

and an example of use:

ref.child("users").child(user.uid).observeSingleEventOfType(.Value, withBlock: { (snapshot) in let user=User(snapshot) user.username="Demo" user.amigos[user.key]=true user.save() })

[callam]

@omarzl nice code you got there

[Jasonchan91]

nice sharing

[choioi]

Very thanks !

[piv199]

@omarzl great way to deal with mapping

[Ankish]

Is there any way we can convert firebase snapshot object to raw json ? Then it could be easy to convert to this. Anythoughts ? Would like to if anyone has searlized snapshot object to JSON and using the mapper - are there any underlying implications of it ?