Setup configuration layer for the library. (#4853)

Author: visumickey

firebase-sessions/src/main/kotlin/com/google/firebase/sessions/SessionInitiator.kt

@@ -20,7 +20,6 @@ import android.app.Activity
 import android.app.Application.ActivityLifecycleCallbacks
 import android.os.Bundle
 import kotlin.time.Duration
-import kotlin.time.Duration.Companion.minutes
 
 /**
  * The [SessionInitiator] is responsible for calling the [initiateSessionStart] callback whenever a
@@ -34,7 +33,6 @@ internal class SessionInitiator(
   private val initiateSessionStart: () -> Unit
 ) {
   private var backgroundTime = elapsedRealtime()
-  private val sessionTimeout = 30.minutes // TODO(mrober): Get session timeout from settings
 
   init {
     initiateSessionStart()
@@ -46,6 +44,7 @@ internal class SessionInitiator(
 
   fun appForegrounded() {
     val interval = elapsedRealtime() - backgroundTime
+    val sessionTimeout = SessionsSettings().sessionRestartTimeout
     if (interval > sessionTimeout) {
       initiateSessionStart()
     }

firebase-sessions/src/main/kotlin/com/google/firebase/sessions/SessionsSettings.kt

@@ -0,0 +1,49 @@
+/*
+ * Copyright 2023 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.firebase.sessions
+
+import kotlin.time.Duration
+import kotlin.time.Duration.Companion.minutes
+
+/**
+ * [SessionsSettings] manages all the configs that are relevant to the sessions library.
+ *
+ * @hide
+ */
+internal class SessionsSettings {
+  // Setting to qualify if sessions service is enabled.
+  val sessionsEnabled: Boolean
+    get() {
+      return true
+    }
+
+  // Setting that provides the sessions sampling rate.
+  val samplingRate: Double
+    get() {
+      return 1.0
+    }
+
+  // Background timeout config value before which a new session is generated
+  val sessionRestartTimeout: Duration
+    get() = 30.minutes
+
+  // Update the settings for all the settings providers
+  fun updateSettings() {
+    // Placeholder to initiate settings update on different sources
+    // Expected sources: RemoteSettings, ManifestOverrides, SDK Defaults
+  }
+}

firebase-sessions/src/test/kotlin/com/google/firebase/sessions/SessionsSettingsTest.kt

@@ -0,0 +1,32 @@
+/*
+ * Copyright 2023 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.firebase.sessions
+
+import com.google.common.truth.Truth.assertThat
+import kotlin.time.Duration.Companion.minutes
+import org.junit.Test
+
+class SessionsSettingsTest {
+
+  @Test
+  fun sessionSettings_fetchDefaults() {
+    val sessionsSettings = SessionsSettings()
+    assertThat(sessionsSettings.sessionsEnabled).isTrue()
+    assertThat(sessionsSettings.samplingRate).isEqualTo(1.0)
+    assertThat(sessionsSettings.sessionRestartTimeout).isEqualTo(30.minutes)
+  }
+}