Firebase Remote Config + Kotlin = EasyFRC

Slide for: GDD Europe 2017 Extended – Milano

Android utility for handle Firebase Remote Config

Firebase Remote Config | What is it?
Change the behavior and appearance of your app without publishing an app update.
Feature:
It’s a cloud service
A simple key-value store
Customize your app for segments of your user base (ex: A/B tests)

Docs: https://firebase.google.com/docs/remote-config/ (+ 3min video)

Transcript

1. Firebase Remote Config + Kotlin = EasyFRC Android utility for handle Firebase Remote Config
2. Omar Miatello Personal profile google.com/+OmarMiatello Google+ Community: Kotlin for Android goo.gl/mUKF1w Slide on Google Presentation goo.gl/1S1Z1E Organizer Android Developer
3. Firebase Remote Config
4. Firebase Remote Config | What is it? Change the behavior and appearance of your app without publishing an app update. Feature: • It’s a cloud service • A simple key-value store • Customize your app for segments of your user base (ex: A/B tests) Docs: https://firebase.google.com/docs/remote-config/ (+ 3min video)
5. Firebase Remote Config | How it works? • Open Firebase console https://console.firebase.google.com • Choose or create a new project • Select “Remote Config” • Add/change/remove parameter • Publish!
6. Firebase Remote Config | API architecture • Singleton exposed to your app • Default Config bundled with your app • Active Config for keep consistency • Fetched Config synced with FRC console values
7. Let’s code! Java version
8. Firebase Remote Config | Configure project | 1/3 1) Add Firebase to your app Add the dependency for Remote Config to your app-level build.gradle file as part of this step: compile 'com.google.firebase:firebase-config:11.4.0' 2) Get the Remote Config singleton object mFirebaseRemoteConfig = FirebaseRemoteConfig.getInstance() 3) Set in-app default parameter values using a Map object or an XML resource file stored in your app's res/xml folder mFirebaseRemoteConfig.setDefaults(R.xml.remote_config_defaults);
9. Firebase Remote Config | Configure project | 2/3 Example of Default Config XML <?xml version="1.0" encoding="utf-8"?> <defaultsMap> <entry> <key>loading_phrase</key> <value>Fetching config…</value> </entry> <entry> <key>secretFeature1_enabled</key> <value>false</value> </entry> </defaultsMap>
10. Firebase Remote Config | Configure project | 3/3 4) Get parameter values to use in your app getBoolean(key) , getByteArray(key), getDouble(key), getLong(key), getString(key) mFirebaseRemoteConfig.getBoolean("secretFeature1_enabled"); 5) Fetch and activate values from the service (as needed) • To fetch parameter values from the Remote Config service, call the fetch() method. Any values that you set in the Remote Config service are fetched and cached in the Remote Config object. • To make fetched parameter values available to your app, call the activateFetched() method.
11. Make it easy… with Kotlin!
12. Kotlin: Properties Declaring Properties val secretFeature1_enabled: Boolean = false Properties: Getters and Setters val secretFeature1_enabled: Boolean get() = FirebaseRemoteConfig.getInstance().getBoolean("secretFeature1_enabled") From code if (secretFeature1_enabled) { // do something … }
13. Kotlin: Delegated Properties | 1/3 There are certain common kinds of properties, that, though we can implement them manually every time we need them, would be very nice to implement once and for all, and put into a library. class Example { val myProperty: String by MyDelegate() }
14. Kotlin: Delegated Properties | 2/3 Define getValue() in your MyDelegate class. class Example { val myProperty: String by MyDelegate() } class MyDelegate { operator fun getValue(thisRef: Any?, property: KProperty<*>): String { return "$thisRef, thank you for delegating '${property.name}' to me!" } }
15. Kotlin: Delegated Properties | 3/3 Providing a delegate (since Koltin 1.1) class Example { val myProperty: String by MyDelegate() } class MyDelegate { operator fun provideDelegate(thisRef: Any?, property: KProperty<*>): ReadOnlyProperty<Any?, T> { // init: check and create delegate } operator fun getValue(thisRef: Any?, property: KProperty<*>): String { return "$thisRef, thank you for delegating '${property.name}' to me!" } }
16. The Goal
17. The Goal Define a class with only properties and defaults object FRC { val signup_useHint by boolean(true) val secretFeature1_enabled by boolean(false) val logMaxLines by int(10) }
18. The Goal | Singleton Define a class with only properties and defaults object FRC { // it’s a singleton! val signup_useHint by boolean(true) val secretFeature1_enabled by boolean(false) val logMaxLines by int(10) }
19. The Goal | Declare config name once Define a class with only properties and defaults object FRC { val signup_useHint by boolean(true) // no need to declare string name! val secretFeature1_enabled by boolean(false) val logMaxLines by int(10) }
20. The Goal | Static type-safe Define a class with only properties and defaults object FRC { val signup_useHint by boolean(true) // it’s a type-safe! val secretFeature1_enabled by boolean(false) val logMaxLines by int(10) }
21. The Goal | Declare default Define a class with only properties and defaults object FRC { val signup_useHint by boolean(true) // has default! val secretFeature1_enabled by boolean(false) val logMaxLines by int(10) }
22. The Goal | Easy to use Define a class with only properties and defaults object FRC { val signup_useHint by boolean(true) val secretFeature1_enabled by boolean(false) val logMaxLines by int(10) } Easy to use in our code (with static type-safe) if (FRC.secretFeature1_enabled) { // do something ... }
23. Build EasyFRC
24. Build EasyFRC | Defaults for initialization abstract class EasyFRC { val _defaults = HashMap<String, Any?>() }
25. Build EasyFRC | Auto setup for Firebase Remote Config abstract class EasyFRC { val _defaults = HashMap<String, Any?>() val frc by lazy { FirebaseRemoteConfig.getInstance().apply { setDefaults(_defaults) activateFetched() fetch() } } }
26. Build EasyFRC | Our Delegate Class abstract class EasyFRC { val _defaults = HashMap<String, Any?>() val frc by lazy { FirebaseRemoteConfig.getInstance().apply { setDefaults(_defaults) activateFetched() fetch() } } class FRCDelegate<T>(val defaultValue: T, val getMethod: (String) -> T) { override fun getValue(thisRef: EasyFRC, property: KProperty<*>) = getMethod(property.name) } }
27. Build EasyFRC | Method for build Delegates | 1/2 abstract class EasyFRC { val _defaults = HashMap<String, Any?>() val frc by lazy { FirebaseRemoteConfig.getInstance().apply { setDefaults(_defaults) activateFetched() fetch() } } fun string(defaultValue: String? = null) = FRCDelegate(defaultValue) { frc.getString(it) } class FRCDelegate<T>(val defaultValue: T, val getMethod: (String) -> T) { override fun getValue(thisRef: EasyFRC, property: KProperty<*>) = getMethod(property.name) } }
28. Build EasyFRC | Method for build Delegates | 2/2 abstract class EasyFRC { // ... fun string(defaultValue: String? = null) = FRCDelegate(defaultValue) { frc.getString(it) } fun boolean(defaultValue: Boolean = false) = FRCDelegate(defaultValue) { frc.getBoolean(it) } // ... class FRCDelegate<T>(val defaultValue: T, val getMethod: (String) -> T) { override fun getValue(thisRef: EasyFRC, property: KProperty<*>) = getMethod(property.name) } }
29. Build EasyFRC | provideDelegate() with Kotlin 1.1 abstract class EasyFRC { // ... fun string(defaultValue: String? = null) = FRCDelegate(defaultValue) { frc.getString(it) } fun boolean(defaultValue: Boolean = false) = FRCDelegate(defaultValue) { frc.getBoolean(it) } // ... class FRCDelegate<T>(val defaultValue: T, val getMethod: (String) -> T) { override fun getValue(thisRef: EasyFRC, property: KProperty<*>) = getMethod(property.name) operator fun provideDelegate(thisRef: EasyFRC, property: KProperty<*>): FRCDelegate<T> { thisRef._defaults.put(property.name, defaultValue) return this } } }
30. Build EasyFRC | The result! object FRC : EasyFRC() { // Basic example val myBoolean by boolean(false) val myInt by int(1337) val myLong by long(134567890123456789) val myDouble by double(0.0) val myString by string("Ciao") val myByteArray by byteArray(ByteArray(0)) // Real world examples val signup_useHint by boolean(true) val secretFeature1_enabled by boolean(false) val secretFeature2_enabled by boolean(true) val cache_expireMax by long(TimeUnit.DAYS.toSeconds(7)) val logMaxLines by int(10) val logLevel by int(Log.INFO) }
31. Mission complete!
32. More complex example ... Added support for: devMode, custom keys, fetch() and fetchAndActivate() Full example: https://github.com/jacklt/jutils Import as dependency (with JitPack)! Gradle (v4 or later): implementation 'com.github.jacklt.jutils:easyfrc:1.0.1' or Gradle (before v4): compile 'com.github.jacklt.jutils:easyfrc:1.0.1'
33. Questions?
34. Let’s try it! https://github.com/jacklt/jutils Thanks!