Can I declare an array to Firebase Remote config?

Question

I am a novice to Android and Firebase. Is it possible to declare an array inside the the Parameter key of Firebase Remote Config?

I want to provide some promotions to some specific models/mobile devices. So if I could declare an array of models(i,e, Samsung J5, Xiaomi Note2 etc) I could easily enable promotions on those models. Please help me.

Answer 1

The Remote Config has recently added the option to save a key-value list by saving it to a JSON format.

Sample usage:

1.Json stored in Remote Configs:

 [
      {
        "lesson": "1",
        "versionCode": 2
      },
      {
        "lesson": "2",
        "versionCode": 4
      },
      {
        "lesson": "3",
        "versionCode": 1
      }
 ]

2.Kotlin model

data class Lesson(val lesson: Int, val versionCode: Int)

3.Retrieve json

String object = FirebaseRemoteConfig.getInstance().getString("test_json");
Gson gson = new GsonBuilder().create();
List<Lesson> lessons = gson.fromJson(object, new TypeToken<List<Lesson>>(){}.getType());

Answer 2

All of the values in Firebase Remote Config are ultimately stored as strings. Booleans, numbers, etc, are all boiled down to strings. The SDK will just parse that string value when you ask for as some other type.

There are no "native" arrays in Remote Config. If you want a series of ordered values in a Remote Config parameter, you should represent it in a way that can be parsed from the string value (such as JSON or some simple delimited strings).

Answer 3

Same as Doug's answer, but with code.

This is in Swift, but you should still get the drift.

For arrays, use a delimited string eg

"iron,wood,gold" and split it into an array of string using .components(separatedBy: ",")

For dictionaries, use a "doubly" delimited string eg

"iron:50, wood:100, gold:2000"

convert it into a dictionary using

    var actualDictionary = [String: Int]()

    // Don't forget the space after the comma
    dictionaryString.components(separatedBy: ", ").forEach({ (entry) in
    let keyValueArray = entry.components(separatedBy: ":")
            return actualDictionary[keyValueArray[0]] = Int(keyValueArray[1])
    })

    return actualDictionary

Answer 4

I like N Kuria's answer, but that requires the whitespace in your json to be exact. If you want something a little more fault tolerant, here is code to read in an array of ints via JSONSerialization.

Let's say you had this array of ints in your json:

 { "array": [1, 5, 4, 3] }

func getArray() -> [Int] {

    let jsonString = "{\"array\": [1, 5, 4, 3]}"
    let array = [Int]()

    guard let data = jsonString.data(using: .utf8) else { return array }
    if let json = try? JSONSerialization.jsonObject(with: data, options: .mutableContainers) {
        guard let theArray = json as? [String: [Int]] else { return array }
        return theArray.first?.value ?? array

        // If you were reading in objects instead of ints, you would do
        // for (key, value) in theArray { /* append values to array */ }
    }

    return array
}

Alternatively, if you were reading in values of a class type, you could just enumerate the dictionary and append to an array with each iteration. (See the comment beneath the first return.)

Answer 5

Firebase stores arrays as objects with integers as key names. You can get an array returned from remote config if you use the Data Type JSON and use an object with sequential keys. For example...

Default Value:

{
  "0": "A",
  "1": "B",
  "2": "C",
  "3": "D",
}

Gets returned as ["A","B","C","D"]

Note they have to be sequential keys! So if the value was:

{
  "0": "A",
  "2": "B",
  "3": "C",
  "4": "D",
}

It would get returned as ["A", undefined, "B", "C","D"]

You can read more about Arrays in Firebase here => https://firebase.blog/posts/2014/04/best-practices-arrays-in-firebase

Answer 6

I would also recommend JSON - as you can have some sort of error detection in parsing the JSON. With splitting, you'll never know if that resulted into a correct array.