Remote Config

Firebase Remote Config

什么是 Remote Config？

Firebase 远程配置是指在 Firebase 后台存储一些键值对，在 app 中向 Firebase 请求并使用这些键值对。当我们需要更改这些键值对时，在 Firebase 后台更改即可。当 app 下一次向 Firebase 请求时，获取到的就是我们更改后的值。这样就实现了动态更新 app 配置。

集成 Remote Config

集成Firebase

方式1：自动 Add Firebase using the Firebase Assistant
Tools > Firebase.

方式2：手动 Add Firebase using the Firebase console

下载 google-services.json 到 app 根目录
root-level (project-level) 添加 gms Gradle 插件

buildscript {

    repositories {
      // Make sure that you have the following two repositories
      google()  // Google's Maven repository
      mavenCentral()  // Maven Central repository
    }

    dependencies {
      ...

      // Add the dependency for the Google services Gradle plugin
      classpath 'com.google.gms:google-services:4.3.15'
    }
}
allprojects {
  ...
  repositories {
    // Make sure that you have the following two repositories
    google()  // Google's Maven repository
    mavenCentral()  // Maven Central repository
  }
}

module (app-level) 引入 GMS 插件

plugins {
    id 'com.android.application'

    // Add the Google services Gradle plugin
    id 'com.google.gms.google-services'
    ...
}

添加 sdk 到 module

dependencies {
  // ...

  // Import the Firebase BoM
  implementation platform('com.google.firebase:firebase-bom:32.0.0')

  // When using the BoM, you don't specify versions in Firebase library dependencies

  // Add the dependency for the Firebase SDK for Google Analytics
  implementation 'com.google.firebase:firebase-analytics-ktx'

  // TODO: Add the dependencies for any other Firebase products you want to use
  // See https://firebase.google.com/docs/android/setup#available-libraries
  // For example, add the dependencies for Firebase Authentication and Cloud Firestore
  implementation 'com.google.firebase:firebase-auth-ktx'
  implementation 'com.google.firebase:firebase-firestore-ktx'
}

引入Remote Config SDK

dependencies {
    // Import the BoM for the Firebase platform
    implementation platform('com.google.firebase:firebase-bom:32.0.0')

    // Add the dependencies for the Remote Config and Analytics libraries
    // When using the BoM, you don't specify versions in Firebase library dependencies
    implementation 'com.google.firebase:firebase-config-ktx'
    implementation 'com.google.firebase:firebase-analytics-ktx'
}

Get the Remote Config singleton object

val remoteConfig: FirebaseRemoteConfig = Firebase.remoteConfig
val configSettings = remoteConfigSettings {
    minimumFetchIntervalInSeconds = 3600 // 最小获取间隔时间，默认12h
}
remoteConfig.setConfigSettingsAsync(configSettings)

Set in-app default parameter values

xml 可参考 remote_config_defaults.xml

<?xml version="1.0" encoding="utf-8"?>
<defaultsMap>
    <entry>
        <key>key_test_remote_config</key>
        <value>here is client default value</value>
    </entry>
    <entry>
        <key>has_discount</key>
        <value>false</value>
    </entry>
    <entry>
        <key>main_color</key>
        <value>red</value>
    </entry>
</defaultsMap>

代码配置

remoteConfig.setDefaultsAsync(R.xml.remote_config_defaults)

Get parameter values to use in your app

Firebase 后台配置值

Parameter name 配置 key
Data Type 配置类型
Default value 配置 value
User in-app default 配置的话，就会从 remote_config_defaults.xml 获取默认值，否则走的是 Default value

Fetch and activate values

Firebase 拉取远程配置后，拉取的键值对默认在本地缓存 12 小时，12 小时后才去重新拉取。如果想要修改缓存时间，在 fetch 中添加时间参数即可，使用 firebaseRemoteConfig.fetch(0)，远程配置的值就会实时更新：

remoteConfig.fetchAndActivate()
    .addOnCompleteListener(this) { task ->
        if (task.isSuccessful) {
            val updated = task.result
            Log.d(TAG, "Config params updated: $updated")
            Toast.makeText(
                this,
                "Fetch and activate succeeded",
                Toast.LENGTH_SHORT,
            ).show()
        } else {
            Toast.makeText(
                this,
                "Fetch failed",
                Toast.LENGTH_SHORT,
            ).show()
        }
        displayWelcomeMessage()
    }

实时监听更新

remoteConfig.addOnConfigUpdateListener(object : ConfigUpdateListener {
    override fun onUpdate(configUpdate : ConfigUpdate) {
       Log.d(TAG, "Updated keys: " + configUpdate.updatedKeys);

       if (configUpdate.updatedKeys.contains("welcome_message")) {
           remoteConfig.activate().addOnCompleteListener {
               displayWelcomeMessage()
           }
       }
    }

    override fun onError(error : FirebaseRemoteConfigException) {
        Log.w(TAG, "Config update error with code: " + error.code, error)
    }
})

下次有新版本的 Remote Config 发布时，运行应用并监听更改的设备便会调用 ConfigUpdateListener。

默认值

Firebase Remote config 中没有配置的 key 的值，默认值
有 key 但没取到，也是默认值
不同类型的默认值

/** The static default string value for any given key. */
public static final String DEFAULT_VALUE_FOR_STRING = "";
/** The static default long value for any given key. */
public static final long DEFAULT_VALUE_FOR_LONG = 0L;
/** The static default double value for any given key. */
public static final double DEFAULT_VALUE_FOR_DOUBLE = 0D;
/** The static default boolean value for any given key. */
public static final boolean DEFAULT_VALUE_FOR_BOOLEAN = false;
/** The static default byte array value for any given key. */
public static final byte[] DEFAULT_VALUE_FOR_BYTE_ARRAY = new byte[0];