04_Coroutines_Homework

README.md

@@ -11,11 +11,11 @@
 ### Добавить к запросу фактов запрос рандомных картинок с https://api.thecatapi.com/v1/images/search
 
 1. На каждый рефреш экрана должен запрашиваться факт + картинка: добавляем сетевой запрос и реализуем логику аналогичную первой задаче. Для загрузки изображений уже подключена библиотека [Picasso](https://github.com/square/picasso)
-2. В метод `view.populate` передаем 1 аргумент, поэтому необходимо реализовать модель презентейшен слоя в которой будут содержаться необходимые данные для рендеринга(текст и ссылка на картинку)
+2. В метод `view.populate` передаем 1 аргумент, поэтому необходимо реализовать модель презентейшен слоя в которой будут содержаться необходимые данные для рендеринга (текст и ссылка на картинку)
 3. Отменятся запросы должны одновременно
 
 ### Реализовать решение ViewModel
 
 1. Реализовать наследника `ViewModel` и продублировать в нем логику из `CatsPresenter`, с необходимыми изменениями. Используйте `viewModelScope` в качестве скоупа.
 2. Добавить логирование ошибок через CoroutineExceptionHanlder. Используйте класс CrashMonitor в качестве фейкового CrashMonitor инструмента
-3. Создать sealed класс `Result`. Унаследовать от него классы `Success<T>`, `Error`. Использовать эти классы как стейт необходимый для рендеринга/отображени ошибки
+3. Создать sealed класс `Result`. Унаследовать от него классы `Success<T>`, `Error`. Использовать эти классы как стейт необходимый для рендеринга/отображения ошибки

app/build.gradle

@@ -5,7 +5,7 @@ plugins {
 
 android {
     namespace = "otus.homework.coroutines"
-    compileSdkVersion 34
+    compileSdkVersion 36
     defaultConfig {
         applicationId "otus.homework.coroutines"
         minSdkVersion 23
@@ -23,22 +23,26 @@ android {
         }
     }
     compileOptions {
-        sourceCompatibility JavaVersion.VERSION_1_8
-        targetCompatibility JavaVersion.VERSION_1_8
+        sourceCompatibility JavaVersion.VERSION_21
+        targetCompatibility JavaVersion.VERSION_21
     }
-    kotlinOptions {
-        jvmTarget = '1.8'
+    kotlin {
+        jvmToolchain(21)
     }
 }
 
 dependencies {
+    //noinspection GradleDependency
     implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
-    implementation 'androidx.core:core-ktx:1.12.0'
-    implementation 'com.squareup.retrofit2:retrofit:2.9.0'
-    implementation 'com.squareup.retrofit2:converter-gson:2.9.0'
-    implementation 'com.google.code.gson:gson:2.10'
-    implementation 'androidx.appcompat:appcompat:1.6.1'
-    implementation 'com.google.android.material:material:1.11.0'
-    implementation 'androidx.constraintlayout:constraintlayout:2.1.4'
+    implementation 'androidx.core:core-ktx:1.17.0'
+    implementation 'com.squareup.retrofit2:retrofit:3.0.0'
+    implementation 'com.squareup.retrofit2:converter-gson:3.0.0'
+    implementation 'com.google.code.gson:gson:2.13.2'
+    implementation 'androidx.appcompat:appcompat:1.7.1'
+    implementation 'com.google.android.material:material:1.13.0'
+    implementation 'androidx.constraintlayout:constraintlayout:2.2.1'
     implementation 'com.squareup.picasso:picasso:2.71828'
+
+    implementation 'androidx.lifecycle:lifecycle-viewmodel-ktx:2.9.4'
+    implementation 'androidx.lifecycle:lifecycle-livedata-ktx:2.9.4'
 }

app/src/main/java/otus/homework/coroutines/CatImage.kt

@@ -0,0 +1,14 @@
+package otus.homework.coroutines
+
+import com.google.gson.annotations.SerializedName
+
+data class CatImage(
+    @SerializedName("url")
+    val url: String,
+    @SerializedName("width")
+    val width: Int,
+    @SerializedName("height")
+    val height: Int,
+    @SerializedName("id")
+    val id: String
+)

app/src/main/java/otus/homework/coroutines/CatPresentation.kt

@@ -0,0 +1,6 @@
+package otus.homework.coroutines
+
+data class CatPresentation(
+    val fact: String,
+    val imageUrl: String
+)

app/src/main/java/otus/homework/coroutines/CatsPresenter.kt

@@ -1,28 +1,49 @@
 package otus.homework.coroutines
 
-import retrofit2.Call
-import retrofit2.Callback
-import retrofit2.Response
+import java.net.SocketTimeoutException
+import kotlin.coroutines.cancellation.CancellationException
+import kotlinx.coroutines.CoroutineName
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.async
+import kotlinx.coroutines.launch
 
 class CatsPresenter(
-    private val catsService: CatsService
+    private val catsService: CatsService,
+    private val catsImageService: CatsImageService
 ) {
 
     private var _catsView: ICatsView? = null
+    private val presenterJob = Job()
+    private val presenterScope = CoroutineScope(
+        Dispatchers.Main + presenterJob + CoroutineName("CatsCoroutine")
+    )
 
     fun onInitComplete() {
-        catsService.getCatFact().enqueue(object : Callback<Fact> {
-
-            override fun onResponse(call: Call<Fact>, response: Response<Fact>) {
-                if (response.isSuccessful && response.body() != null) {
-                    _catsView?.populate(response.body()!!)
-                }
-            }
-
-            override fun onFailure(call: Call<Fact>, t: Throwable) {
+        presenterScope.launch {
+            try {
+                val factDeferred = async { catsService.getCatFact() }
+                val imageDeferred = async { catsImageService.getRandomCatImage() }
+
+                val fact = factDeferred.await()
+                val images = imageDeferred.await()
+
+                val imageUrl = images.firstOrNull()?.url
+                val catPresentation = CatPresentation(
+                    fact = fact.fact,
+                    imageUrl = imageUrl ?: ""
+                )
+                _catsView?.populate(catPresentation)
+            } catch (e: CancellationException) {
+                throw e
+            } catch (e: SocketTimeoutException) {
+                _catsView?.showError(e)
+            } catch (e: Exception) {
                 CrashMonitor.trackWarning()
+                _catsView?.showError(e)
             }
-        })
+        }
     }
 
     fun attachView(catsView: ICatsView) {
@@ -31,5 +52,6 @@ class CatsPresenter(
 
     fun detachView() {
         _catsView = null
+        presenterJob.cancel()
     }
 }

app/src/main/java/otus/homework/coroutines/CatsService.kt

@@ -1,10 +1,15 @@
 package otus.homework.coroutines
 
-import retrofit2.Call
 import retrofit2.http.GET
 
 interface CatsService {
 
     @GET("fact")
-    fun getCatFact() : Call<Fact>
+    suspend fun getCatFact(): Fact
+}
+
+interface CatsImageService {
+
+    @GET("images/search")
+    suspend fun getRandomCatImage(): List<CatImage>
 }

app/src/main/java/otus/homework/coroutines/CatsView.kt

@@ -3,30 +3,50 @@ package otus.homework.coroutines
 import android.content.Context
 import android.util.AttributeSet
 import android.widget.Button
+import android.widget.ImageView
 import android.widget.TextView
+import android.widget.Toast
 import androidx.constraintlayout.widget.ConstraintLayout
+import com.squareup.picasso.Picasso
+import java.net.SocketTimeoutException
 
 class CatsView @JvmOverloads constructor(
     context: Context,
     attrs: AttributeSet? = null,
     defStyleAttr: Int = 0
 ) : ConstraintLayout(context, attrs, defStyleAttr), ICatsView {
 
-    var presenter :CatsPresenter? = null
+    var loadAction: (() -> Unit)? = null
 
     override fun onFinishInflate() {
         super.onFinishInflate()
         findViewById<Button>(R.id.button).setOnClickListener {
-            presenter?.onInitComplete()
+            loadAction?.invoke()
         }
     }
 
-    override fun populate(fact: Fact) {
-        findViewById<TextView>(R.id.fact_textView).text = fact.fact
+    override fun populate(catPresentation: CatPresentation) {
+        findViewById<TextView>(R.id.fact_textView).text = catPresentation.fact
+
+        if (catPresentation.imageUrl.isNotEmpty()) {
+            Picasso.get()
+                .load(catPresentation.imageUrl)
+                .into(findViewById<ImageView>(R.id.cat_imageView))
+        }
+    }
+
+    override fun showError(message: Exception) {
+        val text = when (message) {
+            is SocketTimeoutException -> context.getString(R.string.error_timeout)
+            else -> message.message ?: context.getString(R.string.error_unknown)
+        }
+        Toast.makeText(context, text, Toast.LENGTH_SHORT).show()
     }
+
 }
 
 interface ICatsView {
 
-    fun populate(fact: Fact)
+    fun populate(catPresentation: CatPresentation)
+    fun showError(message: Exception)
 }

app/src/main/java/otus/homework/coroutines/CatsViewModel.kt

@@ -0,0 +1,50 @@
+package otus.homework.coroutines
+
+import androidx.lifecycle.LiveData
+import androidx.lifecycle.MutableLiveData
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.viewModelScope
+import java.net.SocketTimeoutException
+import kotlin.coroutines.cancellation.CancellationException
+import kotlinx.coroutines.CoroutineExceptionHandler
+import kotlinx.coroutines.CoroutineName
+import kotlinx.coroutines.async
+import kotlinx.coroutines.launch
+
+class CatsViewModel(
+    private val catsService: CatsService,
+    private val catsImageService: CatsImageService,
+    private val timeoutErrorMessage: String
+) : ViewModel() {
+
+    private val _catsLiveData = MutableLiveData<Result<CatPresentation>>()
+    val catsLiveData: LiveData<Result<CatPresentation>> = _catsLiveData
+
+    private val exceptionHandler = CoroutineExceptionHandler { _, exception ->
+        CrashMonitor.trackWarning()
+        val error = when (exception) {
+            is SocketTimeoutException -> Exception(timeoutErrorMessage)
+            is CancellationException -> exception
+            else -> exception as? Exception ?: Exception(exception.message)
+        }
+        _catsLiveData.postValue(Result.Error(error))
+    }
+
+    fun loadCatData() {
+        viewModelScope.launch(exceptionHandler + CoroutineName("CatsCoroutine")) {
+            val factDeferred = async { catsService.getCatFact() }
+            val imageDeferred = async { catsImageService.getRandomCatImage() }
+
+            val fact = factDeferred.await()
+            val images = imageDeferred.await()
+
+            val imageUrl = images.firstOrNull()?.url
+            val catPresentation = CatPresentation(
+                fact = fact.fact,
+                imageUrl = imageUrl ?: ""
+            )
+
+            _catsLiveData.value = Result.Success(catPresentation)
+        }
+    }
+}

app/src/main/java/otus/homework/coroutines/DiContainer.kt

@@ -5,12 +5,20 @@ import retrofit2.converter.gson.GsonConverterFactory
 
 class DiContainer {
 
-    private val retrofit by lazy {
+    private val catsFactRetrofit by lazy {
         Retrofit.Builder()
             .baseUrl("https://catfact.ninja/")
             .addConverterFactory(GsonConverterFactory.create())
             .build()
     }
 
-    val service by lazy { retrofit.create(CatsService::class.java) }
+    private val catsImageRetrofit by lazy {
+        Retrofit.Builder()
+            .baseUrl("https://api.thecatapi.com/v1/")
+            .addConverterFactory(GsonConverterFactory.create())
+            .build()
+    }
+
+    val catsService by lazy { catsFactRetrofit.create(CatsService::class.java) }
+    val catsImageService by lazy { catsImageRetrofit.create(CatsImageService::class.java) }
 }

app/src/main/java/otus/homework/coroutines/MainActivity.kt

@@ -1,11 +1,13 @@
 package otus.homework.coroutines
 
-import androidx.appcompat.app.AppCompatActivity
 import android.os.Bundle
+import androidx.appcompat.app.AppCompatActivity
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.ViewModelProvider
 
 class MainActivity : AppCompatActivity() {
 
-    lateinit var catsPresenter: CatsPresenter
+    private lateinit var viewModel: CatsViewModel
 
     private val diContainer = DiContainer()
 
@@ -15,16 +17,28 @@ class MainActivity : AppCompatActivity() {
         val view = layoutInflater.inflate(R.layout.activity_main, null) as CatsView
         setContentView(view)
 
-        catsPresenter = CatsPresenter(diContainer.service)
-        view.presenter = catsPresenter
-        catsPresenter.attachView(view)
-        catsPresenter.onInitComplete()
-    }
-
-    override fun onStop() {
-        if (isFinishing) {
-            catsPresenter.detachView()
+        viewModel = ViewModelProvider(this, object : ViewModelProvider.Factory {
+            override fun <T : ViewModel> create(modelClass: Class<T>): T {
+                if (modelClass.isAssignableFrom(CatsViewModel::class.java)) {
+                    @Suppress("UNCHECKED_CAST")
+                    return CatsViewModel(
+                        diContainer.catsService,
+                        diContainer.catsImageService,
+                        getString(R.string.error_timeout)
+                    ) as T
+                }
+                throw IllegalArgumentException("Unknown ViewModel class")
+            }
+        })[CatsViewModel::class.java]
+
+        viewModel.catsLiveData.observe(this) { result ->
+            when (result) {
+                is Result.Success -> view.populate(result.data)
+                is Result.Error -> view.showError(result.exception)
+            }
         }
-        super.onStop()
+
+        view.loadAction = { viewModel.loadCatData() }
+        viewModel.loadCatData()
     }
 }

app/src/main/java/otus/homework/coroutines/Result.kt

@@ -0,0 +1,6 @@
+package otus.homework.coroutines
+
+sealed class Result<out T> {
+    data class Success<T>(val data: T) : Result<T>()
+    data class Error(val exception: Exception) : Result<Nothing>()
+}