mortenbekditlevsen

//
//  UIDevice+DetectBlur.h
//  BlurTest
//
//  Created by Morten Ditlevsen on 28/01/15.
//  Copyright (c) 2015 Mojo Apps. All rights reserved.
//
 
#import <UIKit/UIKit.h>
 

mortenbekditlevsen

import Foundation

// Note: This code is inspired by the objc.io talk: https://talk.objc.io/episodes/S01E71-type-safe-file-paths-with-phantom-types

// Background: For a project, we were already using Firebase along with RxSwift.
// For this purpose we have a protocol, NetworkServiceType providing the API to the Firebase functionality. The reason for this is that we could potentially switch to a different technology in case we wanted to.
// In this playground I will just write dummy-implementations for NetworkServiceType, FirebaseService and for the RxSwift Observable since these are separate concerns.

// Dummy 'Observable'
enum Observable<T> {

mortenbekditlevsen

I am including parts of the IR code generated for i386 / iphone simulator (where the crash occurs) followed by corresponding parts fom x86_64 (non-crashing):

The crash was due to missing / garbage witness table data for the _JSONStringKeyedDictionaryEncodableMarker, so this is what I have been focusing on - skipping a few occurrances that I somehow don't think are relevant.


i386:
%T10Foundation36_JSONStringDictionaryEncodableMarker33_12768CA107A31EF2DCE034FD75B541C9LLP = type { [12 x i8], %swift.type*, i8** }

x64_64:
%T10Foundation36_JSONStringDictionaryEncodableMarker33_12768CA107A31EF2DCE034FD75B541C9LLP = type { [24 x i8], %swift.type*, i8** }

mortenbekditlevsen

import Foundation
import FirebaseDatabase
import Result

public typealias DecodeResult<T> = Result<T, DecodeError>

public enum DecodeError: Error {
    case noValuePresent
    case conversionError(Error)
}

mortenbekditlevsen

// Instead of this ...

ref.observeSingleEvent(of: .value) { snapshot in
    guard snapshot.exists() else {
        /* HANDLE ERROR */
    }
    guard let value = snapshot.value else {
        /* HANDLE ERROR */
    }
    guard let product = Product(usingMyCustomJSONConversion: value) else {

mortenbekditlevsen

public extension DatabaseQuery {
    func observeSingleEvent<T>(of type: DataEventType,
                               with block: @escaping (DecodeResult<T>) -> Void)
        where T: Decodable {
            observeSingleEvent(of: type) { snap in
                block(snap.decoded())
            }
    }

    func observe<T>(eventType: DataEventType,

mortenbekditlevsen

public extension DatabaseReference {
    func setValue<T>(_ value: T) throws where T: Encodable {
        let encoder = StructureEncoder()
        self.setValue(try encoder.encode(value))
    }
}

mortenbekditlevsen

struct Product: Decodable {
    let name: String
    let price: Decimal
}

let p = Product(name: "Coffee", price: 2.50)
try ref.setValue(p)

mortenbekditlevsen

// So from the Objc.io talk, we learn about a way of representing filesystem paths that can point to either files or directories.
// Internally, these are represented as an array of path elements. Let's do that too:
public struct Path<Element> {

    private var components: [String]

    fileprivate func append<T>(_ args: String ...) -> Path<T> {
        return Path<T>(components + args)
    }

mortenbekditlevsen

//
//  FirebaseService.swift
//  SwiftyFirebase
//
//  Created by Morten Bek Ditlevsen on 29/07/2018.
//  Copyright © 2018 Ka-ching. All rights reserved.
//

import FirebaseDatabase
import Foundation