DataSnapshotDecoder

Use Swift's Decodable with Firebase Realtime Database's DataSnapshot.

Say you have:

import Foundation

struct CoolData: Decodable {
    let hasBindle: Bool
    let interestingItemCount: Int
}

then you can get your list of cool data by:

import FirebaseDatabase

let observer: DataSnapshot -> Void = { snapshot in
    let cools = try! DataSnapshotDecoder().decode([CoolData].self, from: snapshot)
    print("decoded cools! \(cools)")
}

Database.database().reference(withPath: "/cools").observe(.value, with: observer)

No need to round-trip through JSON or manually extract values from the DataSnapshot. All the goodness of Decodable direct from your Firebase Realtime Database. Nested objects, arrays, optionals, it's all there.

DataSnapshotDecoder is an example of a nontrivial, yet straightforward, custom implementation of Foundation.Decoder. If you're navigating that protocol, maybe this example is helpful!

Install

Using CocoaPods

You'll need CocoaPods 1.4 or greater because we depend on FirebaseDatabase, a static framework.

1. Add pod 'DataSnapshotDecoder to your Podfile.
2. Do a pod install.

Then you'll need to import DataSnapshotDecoder in any .swift files where you wish to use it.

Manually

Assuming you already have the FirebaseDatabase framework set up:

1. Download DataSnapshotDecoder.swift. (This is a single-file "library" so this is all you need!)
   • Or add this repository as a git submodule (or equivalent), if you prefer.
2. Drag DataSnapshotDecoder.swift into your Xcode project.

Contribute

Issues and/or pull requests are welcome! Also feel free to email us: hello@mindsea.com.

Fun facts

Need access to your database object's key and/or priority? No problem:

struct CoolKeyedData: Decodable {
    let key: String
    let hasBindle: Bool
    let priority: String?
    
    private enum CodingKeys: String, CodingKey {
        case key = ".key"
        case hasBindle
        case priority = ".priority"
    }
}