QueryGenie

A framework for creating and executing type-safe queries in Swift. Inspired by QueryKit and AlecrimCoreData.

Features

• Core Data Compatibility
• Realm Compatibility
• Automatic attribute generator for Realm.
• Complete Documentation

Usage

Attribute Creation

To use QueryGenie, you first need to add extensions to your model objects providing attributes for all queryable properties on your models. For Realm models, this can be done simply using the RealmGenerator. A generator for CoreData models is planned for future release.

An extension for a User model might look as follows:

extension User {
    static var name:Attribute<String> { return Attribute("name") }
    static var age:Attribute<Int> { return Attribute("age") }
}

Filtering

This allows us to create predicates using our model types.

let namePredicate: NSPredicate = User.name == "Kyle"
let agePredicate: NSPredicate = User.age > 25

These predicates can be used to filter, sort, and execute queries on Queryable entities.

For Realm:

let realm = try! Realm()
let users: Results<User> = realm.objects(User.self)
    .filter { $0.name == "Kyle" }
    .filter { $0.age > 25 }
    .sortedBy(ascending: true) { $0.name } 
    .sortedBy(ascending: false) { $0.age }

For CoreData:

let context = NSManagedObjectContext(concurrencyType: .mainQueue)
let users = Table<User>(context: context)
    .filter { $0.name == "Kyle" }
    .filter { $0.age > 25 }
    .sortedBy(ascending: true) { $0.name }
    .sortedBy(ascending: false) { $0.age }

This library support many other advanced querying capabilities including sum, min, max, average, any, none, and more. For more information, please check out the documentation.

Primary Keys

Model objects that have a primary key may provide an attribute for the primary key in an extension to support querying unique objects.

For Realm, if your object returns a value for primaryKey, all you need to do is make your object conform to UniqueIdentifiable and provide the value type of your primary key. This extension will be generated for you if you use RealmGenerator.

extension User: UniqueIdentifiable {
    public typealias UniqueIdentifierType = String
}

For CoreData, make your object conform to UniqueIdentifiable and provide a static attribute for the primaryKey with the name of the primary key property on your entity.

extension User: UniqueIdentifiable {

    static var primaryKey:Attribute<String> { return Attribute("id") }

}

Automatic Attribute Generation

A Command Line Tool to make automatic attribute generation easier is planned for future release.

QueryGenie provides a helper class to automatically generate attribute extensions for all of your Realm objects. A generator for CoreData is planned for future release.

To use the RealmGenerator, inlcude the QueryGenieRealmGenerator pod in a new test target in your Xcode project.

In that test target, you can create a test that will generate your extensions.

import XCTest

import QueryGenieRealmGenerator
import Realm

class GenerateAttributes: XCTestCase {

    func test_generateAttributes() {
        let path = "/Users/AnthonyMDev/MyProject/Models/QueryGenieExtensions"        
        let url = URL(fileURLWithPath: path, isDirectory: true)
        let config = RLMRealmConfiguration.init()
        config.deleteRealmIfMigrationNeeded = true
        try? RealmGenerator.generateAttributeFiles(for: RLMRealm(configuration: config).schema, destination: url)
    }

}

Installation

CocoaPods

CocoaPods is a dependency manager for Cocoa projects.

To integrate QueryGenie into your Xcode project using CocoaPods, specify it in your Podfile:

source 'https://github.com/CocoaPods/Specs.git'
platform :ios, '8.0'
use_frameworks!

pod 'QueryGenie/Realm', '~> 1.0' // For use with Realm models

pod 'QueryGenie/CoreData', '~> 1.0' // For use with CoreData models

Then, run the following command:

$ pod install