Generic crud operations service for RxFirebaseFirestore

FirestoreService.swift

//
//  FirestoreService.swift
//  Valido-iOS
//
//  Created by Berk Akkerman on 25.06.2020.
//  Copyright © 2020 Ecospend. All rights reserved.
//

import Foundation
import RxSwift
import FirebaseFirestore
import RxFirebaseFirestore

class FirestoreService<T: Codable> {
    
    var collection: FirestoreCollection
    var collectionReference: CollectionReference
    
    init(collection: FirestoreCollection) {
        self.collection = collection
        self.collectionReference = Firestore.firestore().collection(collection.name)
    }
    
    func getAll() -> Observable<[T]> {
        
        return collectionReference
            .rx
            .getDocuments()
            .map { $0.documents.compactMap { $0.data().toCodable(type: T.self) } }
    }
    
    func get(id: String) -> Observable<T?> {
        
        return collectionReference
            .document(id)
            .rx
            .getDocument()
            .map { ($0.data()?.toCodable(type: T.self)) }
    }
    
    func add(item: T) -> Observable<DocumentReference> {
        
        if let itemToAdd = item.dictionary {
            return collectionReference
                .rx
                .addDocument(data: itemToAdd)
        }
        
        return Observable.from(optional: nil)
    }
    
    func update(id: String, item: T) -> Observable<Void> {
        
        if let updateItem = item.dictionary {
            return collectionReference
                .document(id)
                .rx
                .updateData(updateItem)
        }
        
        return Observable<Any>.from(optional: nil).mapToVoid()
    }
}