NetWork Call Using Coroutines

Vimalraj Vijay · Vimalraj Vijay · commit f95d356c16f5 · 2021-01-23T17:34:03.000+05:30
diff --git a/app/build.gradle b/app/build.gradle
@@ -48,23 +48,14 @@ dependencies {
     //Android Activity ViewModel  -- Generates ViewModels()
     implementation "androidx.activity:activity-ktx:1.1.0"
 
-    //Recycler View
-    implementation "androidx.recyclerview:recyclerview:1.1.0"
-    //Glide - Load Images
-    implementation 'com.github.bumptech.glide:glide:4.9.0'
-
     //Android LifeCycle
     implementation 'android.arch.lifecycle:extensions:1.1.1'
     implementation "androidx.lifecycle:lifecycle-viewmodel-ktx:2.2.0"
     implementation "androidx.lifecycle:lifecycle-common-java8:2.2.0"
 
     //Retrofit
     implementation 'com.squareup.retrofit2:retrofit:2.7.2'
-    implementation "com.squareup.retrofit2:adapter-rxjava2:2.7.2"
-
-    //Rx Java
-    implementation 'io.reactivex.rxjava2:rxjava:2.2.18'
-    implementation 'io.reactivex.rxjava2:rxandroid:2.1.1'
+    implementation "com.jakewharton.retrofit:retrofit2-kotlin-coroutines-adapter:0.9.2"
 
     //OkHttp Client and Logger
     implementation "com.squareup.okhttp3:okhttp:3.14.7"
@@ -74,6 +65,11 @@ dependencies {
     implementation 'com.google.code.gson:gson:2.8.5'
     implementation 'com.squareup.retrofit2:converter-gson:2.7.2'
 
+    // Coroutines
+    def kotlinCoroutineVersion = "1.3.0"
+    implementation "org.jetbrains.kotlinx:kotlinx-coroutines-android:$kotlinCoroutineVersion"
+    implementation "org.jetbrains.kotlinx:kotlinx-coroutines-core:$kotlinCoroutineVersion"
+
     //Dagger Hilt
     implementation "com.google.dagger:hilt-android:$hilt_version"
     kapt "com.google.dagger:hilt-android-compiler:$hilt_version"
diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
@@ -11,7 +11,7 @@
         android:roundIcon="@mipmap/ic_launcher_round"
         android:supportsRtl="true"
         android:theme="@style/Theme.Dagger2">
-        <activity android:name=".MainActivity">
+        <activity android:name=".main.ui.MainActivity">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
 
diff --git a/app/src/main/java/com/vimalvijay/dagger2/di/ApplicationController.kt b/app/src/main/java/com/vimalvijay/dagger2/di/ApplicationController.kt
@@ -4,10 +4,6 @@ import android.app.Application
 import dagger.hilt.android.HiltAndroidApp
 
 @HiltAndroidApp
-class ApplicationController :Application(){
-
-    override fun onCreate() {
-        super.onCreate()
-    }
+class ApplicationController : Application() {
 
 }
diff --git a/app/src/main/java/com/vimalvijay/dagger2/di/modules/AppModule.kt b/app/src/main/java/com/vimalvijay/dagger2/di/modules/AppModule.kt
@@ -1,5 +1,6 @@
 package com.vimalvijay.dagger2.di.modules
 
+import com.jakewharton.retrofit2.adapter.kotlin.coroutines.CoroutineCallAdapterFactory
 import com.vimalvijay.dagger2.BuildConfig
 import com.vimalvijay.dagger2.network.ApiConstants
 import com.vimalvijay.dagger2.network.ApiService
@@ -10,21 +11,25 @@ import dagger.hilt.android.components.ApplicationComponent
 import okhttp3.OkHttpClient
 import okhttp3.logging.HttpLoggingInterceptor
 import retrofit2.Retrofit
-import retrofit2.adapter.rxjava2.RxJava2CallAdapterFactory
 import retrofit2.converter.gson.GsonConverterFactory
 import javax.inject.Singleton
 
 
 @Module
 @InstallIn(ApplicationComponent::class)
 class AppModule {
-
+    /**
+     * Application's Base URL
+     */
     @Provides
     fun providesAppBaseURL() = ApiConstants.BASE_URL
 
+    /**
+     * Logger For API
+     */
     @Provides
     @Singleton
-    fun provideOkHttpClient() = if (BuildConfig.DEBUG) {
+    fun provideOkHttpClient(): OkHttpClient = if (BuildConfig.DEBUG) {
         val loggingInterceptor = HttpLoggingInterceptor()
         loggingInterceptor.level = HttpLoggingInterceptor.Level.BODY
         OkHttpClient.Builder()
@@ -34,17 +39,23 @@ class AppModule {
         .Builder()
         .build()
 
+    /**
+     * Init Retrofit Client for Network
+     */
     @Provides
     @Singleton
     fun provideRetrofit(okHttpClient: OkHttpClient, BASE_URL: String): Retrofit =
         Retrofit.Builder()
             .addConverterFactory(GsonConverterFactory.create())
-            .addCallAdapterFactory(RxJava2CallAdapterFactory.create())
+            .addCallAdapterFactory(CoroutineCallAdapterFactory())
             .baseUrl(BASE_URL)
             .client(okHttpClient)
             .build()
 
+    /**
+     * Api Provider
+     */
     @Provides
     @Singleton
-    fun provideApiService(retrofit: Retrofit) = retrofit.create(ApiService::class.java)
+    fun provideApiService(retrofit: Retrofit): ApiService = retrofit.create(ApiService::class.java)
 }
diff --git a/app/src/main/java/com/vimalvijay/dagger2/main/repository/MainRepository.kt b/app/src/main/java/com/vimalvijay/dagger2/main/repository/MainRepository.kt
@@ -1,33 +1,22 @@
 package com.vimalvijay.dagger2.main.repository
 
-import androidx.lifecycle.MutableLiveData
 import com.vimalvijay.dagger2.main.model.Hero
 import com.vimalvijay.dagger2.network.ApiService
-import retrofit2.Call
-import retrofit2.Callback
-import retrofit2.Response
+import com.vimalvijay.dagger2.network.BaseRepository
 import javax.inject.Inject
 
 
-class MainRepository @Inject constructor(var apiService: ApiService) {
+class MainRepository @Inject constructor(var apiService: ApiService) : BaseRepository() {
 
-    val heroList: MutableLiveData<Hero> = MutableLiveData()
+    /**
+     * Get Hero List from Api
+     */
+    suspend fun getHerosList(): MutableList<Hero.HeroItem>? {
 
-
-    fun getHeroListCall(): MutableLiveData<Hero> {
-        apiService.getHeroes().enqueue(object : Callback<Hero?> {
-            override fun onFailure(call: Call<Hero?>, t: Throwable) {
-                println("Error throw ${t.localizedMessage}")
-                heroList.postValue(null)
-            }
-
-            override fun onResponse(call: Call<Hero?>, response: Response<Hero?>) {
-                val callheroList: Hero = response.body() as Hero
-                heroList.value = response.body()
-            }
-
-        })
-
-        return heroList
+        val heroResponse = safeApiRequest(
+            call = { apiService.getHeroes().await() },
+            errorMessage = "Error On" + Thread.currentThread().stackTrace[1].methodName
+        )
+        return heroResponse?.toMutableList()
     }
 }
diff --git a/app/src/main/java/com/vimalvijay/dagger2/main/ui/MainActivity.kt b/app/src/main/java/com/vimalvijay/dagger2/main/ui/MainActivity.kt
@@ -1,4 +1,4 @@
-package com.vimalvijay.dagger2
+package com.vimalvijay.dagger2.main.ui
 
 import android.os.Bundle
 import android.view.LayoutInflater
@@ -8,6 +8,7 @@ import android.widget.TextView
 import androidx.activity.viewModels
 import androidx.appcompat.app.AppCompatActivity
 import androidx.lifecycle.Observer
+import com.vimalvijay.dagger2.R
 import com.vimalvijay.dagger2.main.model.Hero
 import com.vimalvijay.dagger2.main.viewmodel.MainViewModel
 import dagger.hilt.android.AndroidEntryPoint
@@ -23,19 +24,26 @@ class MainActivity : AppCompatActivity() {
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         setContentView(R.layout.activity_main)
-        mainViewModel.getHerosRepository().observe(this, object : Observer<Hero> {
-            override fun onChanged(t: Hero?) {
-                t?.let { generateView(it) }
-            }
-        })
+
+        /**
+         * Fetch
+         */
+        mainViewModel.fetchHerosList()
+        /**
+         * Observe Using Live data
+         */
+        mainViewModel.heroListLiveData.observe(this, Observer<MutableList<Hero.HeroItem>> { t -> generateView(t) })
     }
 
-    private fun generateView(hero: Hero) {
+    /**
+     * Set Views
+     */
+    private fun generateView(hero: MutableList<Hero.HeroItem>?) {
         val parentLayout = findViewById<LinearLayout>(R.id.llt_heros_list)
         val layoutInflater: LayoutInflater = layoutInflater
 
         parentLayout.removeAllViews()
-        for (i in hero.indices) {
+        for (i in hero?.indices!!) {
             view = layoutInflater.inflate(R.layout.heros_name_list, parentLayout, false)
             val tvHeroNames = view.findViewById<TextView>(R.id.tv_hero_names)
             tvHeroNames.text = hero[i].name
diff --git a/app/src/main/java/com/vimalvijay/dagger2/main/viewmodel/MainViewModel.kt b/app/src/main/java/com/vimalvijay/dagger2/main/viewmodel/MainViewModel.kt
@@ -5,18 +5,31 @@ import androidx.lifecycle.MutableLiveData
 import androidx.lifecycle.ViewModel
 import com.vimalvijay.dagger2.main.model.Hero
 import com.vimalvijay.dagger2.main.repository.MainRepository
+import kotlinx.coroutines.*
+import kotlin.coroutines.CoroutineContext
 
 class MainViewModel @ViewModelInject constructor(private var mainRepository: MainRepository) :
     ViewModel() {
 
-    var heroList: MutableLiveData<Hero> = MutableLiveData()
+    private val parentJob = Job()
 
-    fun getHerosRepository(): MutableLiveData<Hero> {
-        heroList = loadHerosList()
-        return heroList
+    private val coroutineContext: CoroutineContext
+        get() = parentJob + Dispatchers.Default
+
+    private val scope = CoroutineScope(coroutineContext)
+
+    val heroListLiveData = MutableLiveData<MutableList<Hero.HeroItem>>()
+
+    /**
+     * Launch API using Coroutines
+     */
+    fun fetchHerosList() {
+        scope.launch {
+            heroListLiveData.postValue(mainRepository.getHerosList())
+        }
     }
 
-    private fun loadHerosList(): MutableLiveData<Hero> {
-        return mainRepository.getHeroListCall()
+    fun cancelAllRequest() {
+        coroutineContext.cancel()
     }
-}
+}
diff --git a/app/src/main/java/com/vimalvijay/dagger2/network/ApiConstants.kt b/app/src/main/java/com/vimalvijay/dagger2/network/ApiConstants.kt
@@ -2,8 +2,4 @@ package com.vimalvijay.dagger2.network
 
 object ApiConstants {
     const val BASE_URL = "https://simplifiedcoding.net/demos/"
-
-    const val RESPONSE_SUCCESS = "Success"
-    const val RESPONSE_FAILURE = "Failure"
-    const val RESPONSE_LOADING = "Loading"
 }
diff --git a/app/src/main/java/com/vimalvijay/dagger2/network/ApiService.kt b/app/src/main/java/com/vimalvijay/dagger2/network/ApiService.kt
@@ -1,19 +1,13 @@
 package com.vimalvijay.dagger2.network
 
 import com.vimalvijay.dagger2.main.model.Hero
-import io.reactivex.Single
-import retrofit2.Call
+import kotlinx.coroutines.Deferred
+import retrofit2.Response
 import retrofit2.http.GET
 
 interface ApiService {
 
     @GET("marvel")
-    fun getHeroes(): Call<Hero>
-
-    /*@GET("repos/{owner}/{name}")
-    fun getRepo(
-        @Path("owner") owner: String?,
-        @Path("name") name: String?
-    ): Single<Repo?>?*/
+    fun getHeroes(): Deferred<Response<Hero>>
 
 }
diff --git a/app/src/main/java/com/vimalvijay/dagger2/network/BaseRepository.kt b/app/src/main/java/com/vimalvijay/dagger2/network/BaseRepository.kt
@@ -0,0 +1,41 @@
+package com.vimalvijay.dagger2.network
+
+import android.util.Log
+import retrofit2.Response
+import java.io.IOException
+
+open class BaseRepository {
+
+    /**
+     * Api Calling
+     */
+    suspend fun <T : Any> safeApiRequest(
+        call: suspend () -> Response<T>,
+        errorMessage: String
+    ): T? {
+        val result: NetworkResultHandler<T> = safeApiResult(call, errorMessage)
+        var data: T? = null
+
+        when (result) {
+            is NetworkResultHandler.OnSuccessResponse ->
+                data = result.response
+            is NetworkResultHandler.OnFailureResponse ->
+                Log.d("1.DataRepository", "$errorMessage & Exception - ${result.exception}")
+        }
+
+        return data
+    }
+
+    /**
+     * NetWork Result Handler
+     */
+    private suspend fun <T : Any> safeApiResult(
+        call: suspend () -> Response<T>,
+        errorMessage: String
+    ): NetworkResultHandler<T> {
+        val response = call.invoke()
+        if (response.isSuccessful) return NetworkResultHandler.OnSuccessResponse(response.body()!!)
+
+        return NetworkResultHandler.OnFailureResponse(IOException("Error Occurred during getting safe Api result, Custom ERROR - $errorMessage"))
+    }
+}
diff --git a/app/src/main/java/com/vimalvijay/dagger2/network/NetworkResultHandler.kt b/app/src/main/java/com/vimalvijay/dagger2/network/NetworkResultHandler.kt
@@ -0,0 +1,6 @@
+package com.vimalvijay.dagger2.network
+
+sealed class NetworkResultHandler<out T : Any> {
+    data class OnSuccessResponse<out T : Any>(val response: T) : NetworkResultHandler<T>()
+    data class OnFailureResponse(val exception: Exception) : NetworkResultHandler<Nothing>()
+}
diff --git a/app/src/main/res/layout/activity_main.xml b/app/src/main/res/layout/activity_main.xml
@@ -4,7 +4,7 @@
     xmlns:tools="http://schemas.android.com/tools"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
-    tools:context=".MainActivity">
+    tools:context=".main.ui.MainActivity">
 
     <LinearLayout
         android:id="@+id/llt_heros_list"

Original file line number	Diff line number	Diff line change
`@@ -2,8 +2,4 @@ package com.vimalvijay.dagger2.network`
`2`	`2`
`3`	`3`	`object ApiConstants {`
`4`	`4`	`const val BASE_URL = "https://simplifiedcoding.net/demos/"`
`5`		`-`
`6`		`- const val RESPONSE_SUCCESS = "Success"`
`7`		`- const val RESPONSE_FAILURE = "Failure"`
`8`		`- const val RESPONSE_LOADING = "Loading"`
`9`	`5`	`}`