Fix #3322: Platform parameter singleton and Generic Interface (#3323)

* This PR introduces new Proto Classes which will be used to implement Platform Parameter project in Oppia-Android. This PR will is reffered as PR-1.1 in the Milestones

* Lint check correction

* Removing unnecessary spaces

* Changed the name of Parameter class to PlatformParameter and included the oneof type field in ParameterWithName

* Changed the names of all the other classes to include PlatformParameter in their name

* nit space change

* Reverting back to previous structure

* Suggested changes by Ben about spacing, renaming, docs and removing PlatformParameterMap

* Modifying BUILD.bazel to include platform_parameter.proto

* Changed the visibility in BUILD.bazel

* removed unnecessary visibility in BUILD.bazel

* Nit indentation change

* Suggested changes to remove the PlatformParameterWithName message and use only one PlatformParameter message everywhere

* Added a Singleton and Generic Interface to help with Providing Platform Parameters

* Added PlatformParameterSingletonTest and tweaked PlatformParameterSingleton

* Added new tests and tweaked the documentation to include KDBlocks

* Adding the dependency over PlatformParameter Proto Classes

* Using a default setter for platformParameterMap, and changed the tests to have a constant mockPlatformParameterMap instead of creating it again. Also changed the KDocs for generic interface

* Lint checks

* Renaming variables and changing KDocs

* Replaced the use of generic getter function to three separate functions for String/Int/Boolean type parameters. Also updated the tests accordingly

* Modified test cases to include check for double initialization of platformParameterMap and also to check that singleton returns null in case the wrong type of Parameter is asked

* Nit spacing changes

* using assertThat().isNotEqualTo() in place of current assert statements also correct lint checks

* Lint check

* Rearrange imports with ktlint

* KDoc changes, Renamed generic Interface to PlatformParameterValue and used PlatformParameter.newBuilder() instead of getDefaultInstance in the mockPlatformParameterMap

* Bazel changes for including PlatformParameter in the KDoc of PlatformParameterValue Interface

* Nit fix to prevent type inference warning

* Reverted auto generated changes

* Changed all the KDoc Format as suggested

* Changed the approach to have an PlatformParameterSingleton interface and its Impl. Also changed the tests accordingly

* Nit spacing changes

* Using mutableMap instead for PlatformParameterMap in Singleton

domain/BUILD.bazel

@@ -80,6 +80,7 @@ kt_android_library(
  "//domain/src/main/java/org/oppia/android/domain/util:retriever",
  "//model:exploration_checkpoint_java_proto_lite",
  "//model:onboarding_java_proto_lite",
+ "//model:platform_parameter_java_proto_lite",
  "//model:question_java_proto_lite",
  "//model:topic_java_proto_lite",
  "//third_party:androidx_work_work-runtime-ktx",

domain/src/main/java/org/oppia/android/domain/platformparameter/PlatformParameterSingletonImpl.kt

@@ -0,0 +1,55 @@
+package org.oppia.android.domain.platformparameter
+
+import org.oppia.android.app.model.PlatformParameter
+import org.oppia.android.util.platformparameter.PlatformParameterSingleton
+import org.oppia.android.util.platformparameter.PlatformParameterValue
+import javax.inject.Inject
+import javax.inject.Singleton
+
+/** Singleton which helps in storing and providing Platform Parameters at runtime. */
+@Singleton
+class PlatformParameterSingletonImpl @Inject constructor() : PlatformParameterSingleton {
+ private val platformParameterMap = mutableMapOf<String, PlatformParameter>()
+
+ override fun getPlatformParameterMap() = platformParameterMap
+
+ override fun setPlatformParameterMap(platformParameterMap: Map<String, PlatformParameter>) {
+ if (this.platformParameterMap.isEmpty()) this.platformParameterMap.putAll(platformParameterMap)
+ }
+
+ override fun getStringPlatformParameter(
+ platformParameterName: String
+ ): PlatformParameterValue<String>? {
+ if (platformParameterMap.isEmpty()) return null
+ val parameter = platformParameterMap[platformParameterName] ?: return null
+ if (!parameter.valueTypeCase.equals(PlatformParameter.ValueTypeCase.STRING)) return null
+ return object : PlatformParameterValue<String> {
+ override val value: String
+ get() = parameter.string
+ }
+ }
+
+ override fun getIntegerPlatformParameter(
+ platformParameterName: String
+ ): PlatformParameterValue<Int>? {
+ if (platformParameterMap.isEmpty()) return null
+ val parameter = platformParameterMap[platformParameterName] ?: return null
+ if (!parameter.valueTypeCase.equals(PlatformParameter.ValueTypeCase.INTEGER)) return null
+ return object : PlatformParameterValue<Int> {
+ override val value: Int
+ get() = parameter.integer
+ }
+ }
+
+ override fun getBooleanPlatformParameter(
+ platformParameterName: String
+ ): PlatformParameterValue<Boolean>? {
+ if (platformParameterMap.isEmpty()) return null
+ val parameter = platformParameterMap[platformParameterName] ?: return null
+ if (!parameter.valueTypeCase.equals(PlatformParameter.ValueTypeCase.BOOLEAN)) return null
+ return object : PlatformParameterValue<Boolean> {
+ override val value: Boolean
+ get() = parameter.boolean
+ }
+ }
+}

domain/src/test/java/org/oppia/android/domain/platformparameter/PlatformParameterSingletonTest.kt

@@ -0,0 +1,177 @@
+package org.oppia.android.domain.platformparameter
+
+import android.app.Application
+import androidx.test.core.app.ApplicationProvider
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import com.google.common.truth.Truth.assertThat
+import dagger.BindsInstance
+import dagger.Component
+import dagger.Module
+import dagger.Provides
+import org.junit.Before
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.oppia.android.app.model.PlatformParameter
+import org.oppia.android.util.platformparameter.PlatformParameterSingleton
+import org.oppia.android.util.platformparameter.PlatformParameterValue
+import org.robolectric.annotation.Config
+import org.robolectric.annotation.LooperMode
+import javax.inject.Inject
+import javax.inject.Singleton
+
+private const val STRING_PLATFORM_PARAMETER_NAME = "string_platform_parameter_name"
+private const val STRING_PLATFORM_PARAMETER_VALUE = "string_platform_parameter_value"
+
+private const val INTEGER_PLATFORM_PARAMETER_NAME = "integer_platform_parameter_name"
+private const val INTEGER_PLATFORM_PARAMETER_VALUE = 1
+
+private const val BOOLEAN_PLATFORM_PARAMETER_NAME = "boolean_platform_parameter_name"
+private const val BOOLEAN_PLATFORM_PARAMETER_VALUE = true
+
+private const val INCORRECT_PLATFORM_PARAMETER_NAME = "incorrect_platform_parameter_name"
+
+/**
+ * [PlatformParameterSingletonTest] verifies the working of [PlatformParameterSingleton] by testing
+ * the [PlatformParameterValue] received in different cases
+ */
+@RunWith(AndroidJUnit4::class)
+@LooperMode(LooperMode.Mode.PAUSED)
+@Config(application = PlatformParameterSingletonTest.TestApplication::class)
+class PlatformParameterSingletonTest {
+
+ @Inject
+ lateinit var platformParameterSingleton: PlatformParameterSingleton
+
+ private val mockPlatformParameterMap by lazy {
+ val stringPlatformParameter = PlatformParameter.newBuilder()
+ .setString(STRING_PLATFORM_PARAMETER_VALUE).build()
+ val integerPlatformParameter = PlatformParameter.newBuilder()
+ .setInteger(INTEGER_PLATFORM_PARAMETER_VALUE).build()
+ val booleanPlatformParameter = PlatformParameter.newBuilder()
+ .setBoolean(BOOLEAN_PLATFORM_PARAMETER_VALUE).build()
+
+ mapOf<String, PlatformParameter>(
+ STRING_PLATFORM_PARAMETER_NAME to stringPlatformParameter,
+ INTEGER_PLATFORM_PARAMETER_NAME to integerPlatformParameter,
+ BOOLEAN_PLATFORM_PARAMETER_NAME to booleanPlatformParameter,
+ )
+ }
+
+ @Before
+ fun setUp() {
+ setUpTestApplicationComponent()
+ }
+
+ @Test
+ fun testSingleton_initPlatformParameterMap_isEmpty() {
+ assertThat(platformParameterSingleton.getPlatformParameterMap()).isEmpty()
+ }
+
+ @Test
+ fun testSingleton_initPlatformParameterMap_isNotEmpty() {
+ assertThat(platformParameterSingleton.getPlatformParameterMap()).isEmpty()
+ platformParameterSingleton.setPlatformParameterMap(mockPlatformParameterMap)
+ assertThat(platformParameterSingleton.getPlatformParameterMap()).isNotEmpty()
+ }
+
+ @Test
+ fun testSingleton_initPlatformParameterMapTwice_checkIsNotUpdatedTwice() {
+ platformParameterSingleton.setPlatformParameterMap(mockPlatformParameterMap)
+ assertThat(platformParameterSingleton.getPlatformParameterMap()).isNotEmpty()
+
+ val emptyPlatformParameterMap = mapOf<String, PlatformParameter>()
+ platformParameterSingleton.setPlatformParameterMap(emptyPlatformParameterMap)
+
+ assertThat(
+ platformParameterSingleton.getPlatformParameterMap()
+ ).isNotEqualTo(emptyPlatformParameterMap)
+ assertThat(
+ platformParameterSingleton.getPlatformParameterMap()
+ ).isEqualTo(mockPlatformParameterMap)
+ }
+
+ @Test
+ fun testSingleton_initPlatformParameterMap_retrieveStringParameter_verifyItsValue() {
+ platformParameterSingleton.setPlatformParameterMap(mockPlatformParameterMap)
+ val stringPlatformParameter = platformParameterSingleton.getStringPlatformParameter(
+ STRING_PLATFORM_PARAMETER_NAME
+ )
+ assertThat(stringPlatformParameter?.value).isEqualTo(STRING_PLATFORM_PARAMETER_VALUE)
+ }
+
+ @Test
+ fun testSingleton_initPlatformParameterMap_retrieveIntegerParameter_verifyItsValue() {
+ platformParameterSingleton.setPlatformParameterMap(mockPlatformParameterMap)
+ val integerPlatformParameter = platformParameterSingleton.getIntegerPlatformParameter(
+ INTEGER_PLATFORM_PARAMETER_NAME
+ )
+ assertThat(integerPlatformParameter?.value).isEqualTo(INTEGER_PLATFORM_PARAMETER_VALUE)
+ }
+
+ @Test
+ fun testSingleton_initPlatformParameterMap_retrieveBooleanParameter_verifyItsValue() {
+ platformParameterSingleton.setPlatformParameterMap(mockPlatformParameterMap)
+ val booleanPlatformParameter = platformParameterSingleton.getBooleanPlatformParameter(
+ BOOLEAN_PLATFORM_PARAMETER_NAME
+ )
+ assertThat(booleanPlatformParameter?.value).isEqualTo(BOOLEAN_PLATFORM_PARAMETER_VALUE)
+ }
+
+ @Test
+ fun testSingleton_initPlatformParameterMap_retrieveIncorrectNamedParameter_verifyIsNull() {
+ platformParameterSingleton.setPlatformParameterMap(mockPlatformParameterMap)
+ val incorrectPlatformParameter = platformParameterSingleton.getStringPlatformParameter(
+ INCORRECT_PLATFORM_PARAMETER_NAME
+ )
+ assertThat(incorrectPlatformParameter).isNull()
+ }
+
+ @Test
+ fun testSingleton_initPlatformParameterMap_retrieveIncorrectTypeParameter_verifyIsNull() {
+ platformParameterSingleton.setPlatformParameterMap(mockPlatformParameterMap)
+ val incorrectPlatformParameter = platformParameterSingleton.getStringPlatformParameter(
+ BOOLEAN_PLATFORM_PARAMETER_NAME
+ )
+ assertThat(incorrectPlatformParameter).isNull()
+ }
+
+ private fun setUpTestApplicationComponent() {
+ ApplicationProvider.getApplicationContext<TestApplication>().inject(this)
+ }
+
+ @Module
+ class TestModule {
+ @Provides
+ fun providePlatformParameterSingleton(
+ platformParameterSingletonImpl: PlatformParameterSingletonImpl
+ ): PlatformParameterSingleton = platformParameterSingletonImpl
+ }
+
+ // TODO(#89): Move this to a common test application component.
+ @Singleton
+ @Component(
+ modules = [TestModule::class]
+ )
+ interface TestApplicationComponent {
+ @Component.Builder
+ interface Builder {
+ @BindsInstance
+ fun setApplication(application: Application): Builder
+ fun build(): PlatformParameterSingletonTest.TestApplicationComponent
+ }
+
+ fun inject(platformParameterSingletonTest: PlatformParameterSingletonTest)
+ }
+
+ class TestApplication : Application() {
+ private val component: PlatformParameterSingletonTest.TestApplicationComponent by lazy {
+ DaggerPlatformParameterSingletonTest_TestApplicationComponent.builder()
+ .setApplication(this)
+ .build()
+ }
+
+ fun inject(platformParameterSingletonTest: PlatformParameterSingletonTest) {
+ component.inject(platformParameterSingletonTest)
+ }
+ }
+}

utility/BUILD.bazel

@@ -48,6 +48,7 @@ kt_android_library(
  "//app:crashlytics",
  "//app:crashlytics_deps",
  "//model:event_logger_java_proto_lite",
+ "//model:platform_parameter_java_proto_lite",
  "//third_party:androidx_appcompat_appcompat",
  "//third_party:androidx_room_room-runtime",
  "//third_party:androidx_work_work-runtime",

utility/src/main/java/org/oppia/android/util/platformparameter/PlatformParameterSingleton.kt

@@ -0,0 +1,46 @@
+package org.oppia.android.util.platformparameter
+
+import org.oppia.android.app.model.PlatformParameter
+
+/** Singleton which helps in storing and providing Platform Parameters at runtime. */
+interface PlatformParameterSingleton {
+
+ /**
+ * Gets the current platformParameterMap.
+ *
+ * @return [Map<String, PlatformParameter>]
+ */
+ fun getPlatformParameterMap(): Map<String, PlatformParameter>
+
+ /**
+ * Initializes a platformParameterMap in case it is empty.
+ *
+ * @param platformParameterMap [Map<String, PlatformParameter>]
+ * @return [Unit]
+ */
+ fun setPlatformParameterMap(platformParameterMap: Map<String, PlatformParameter>)
+
+ /**
+ * Retrieves a String type Platform Parameter, if it exists in the platformParameterMap.
+ *
+ * @param platformParameterName [String], Name of the String type Platform Parameter.
+ * @return [PlatformParameterValue]? which contains the value for String type Platform Parameter
+ */
+ fun getStringPlatformParameter(platformParameterName: String): PlatformParameterValue<String>?
+
+ /**
+ * Retrieves a Integer type Platform Parameter, if it exists in the platformParameterMap.
+ *
+ * @param platformParameterName [String], Name of the Integer type Platform Parameter.
+ * @return [PlatformParameterValue]? which contains the value for Integer type Platform Parameter
+ */
+ fun getIntegerPlatformParameter(platformParameterName: String): PlatformParameterValue<Int>?
+
+ /**
+ * Retrieves a Boolean type Platform Parameter, if it exists in the platformParameterMap.
+ *
+ * @param platformParameterName [String], Name of the Boolean type Platform Parameter.
+ * @return [PlatformParameterValue]? which contains the value for Boolean type Platform Parameter
+ */
+ fun getBooleanPlatformParameter(platformParameterName: String): PlatformParameterValue<Boolean>?
+}

utility/src/main/java/org/oppia/android/util/platformparameter/PlatformParameterValue.kt

@@ -0,0 +1,12 @@
+package org.oppia.android.util.platformparameter
+
+import org.oppia.android.app.model.PlatformParameter
+
+/**
+ * Generic interface that is used to provide platform parameter values corresponding to the
+ * [PlatformParameter] proto values. Objects that implement this interface will override the [value]
+ * property to store the actual platform parameter value.
+ */
+interface PlatformParameterValue<T> {
+ val value: T
+}