implement viewmodel, domain layer and view layer for userlist

app/build.gradle

@@ -15,6 +15,9 @@ android {
         versionCode 1
         versionName "1.0"
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
+
+        buildConfigField "String", "DB_NAME", '"friendlists.db"'
+        buildConfigField "String", "BASE_ENDPOINT", '"https://jsonplaceholder.typicode.com/"'
     }
 
     buildTypes {

app/src/main/AndroidManifest.xml

@@ -1,6 +1,8 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
     package="com.hako.friendlists">
 
+    <uses-permission android:name="android.permission.INTERNET"/>
+
     <application
         android:name=".MainApplication"
         android:allowBackup="true"

app/src/main/java/com/hako/friendlists/MainApplication.kt

@@ -1,7 +1,8 @@
 package com.hako.friendlists
 
 import android.app.Application
-import com.hako.base.di.baseModule
+import com.hako.friendlist.di.userlistModules
+import com.hako.friendlists.di.appModules
 import org.koin.android.ext.koin.androidContext
 import org.koin.core.context.startKoin
 import timber.log.Timber
@@ -24,7 +25,8 @@ class MainApplication : Application() {
 
             modules(
                 listOf(
-                    baseModule
+                    appModules,
+                    userlistModules
                 )
             )
         }

app/src/main/java/com/hako/friendlists/di/AppModules.kt

@@ -0,0 +1,18 @@
+package com.hako.friendlists.di
+
+import androidx.room.Room
+import com.hako.base.domain.database.DatabaseClient
+import com.hako.base.domain.network.RemoteClient
+import com.hako.friendlists.BuildConfig
+import org.koin.dsl.module
+
+val appModules = module {
+    // Room database
+    single { Room.databaseBuilder(get(), DatabaseClient::class.java, BuildConfig.DB_NAME).build() }
+    factory { get<DatabaseClient>().userDao() }
+    factory { get<DatabaseClient>().albumDao() }
+    factory { get<DatabaseClient>().photoDao() }
+
+    // Retrofit
+    single { RemoteClient(BuildConfig.BASE_ENDPOINT) }
+}

base/build.gradle

@@ -12,8 +12,6 @@ android {
         minSdkVersion build_versions.min_sdk
         targetSdkVersion build_versions.target_sdk
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
-
-        buildConfigField "String", "DB_NAME", '"friendlists.db"'
     }
 
     compileOptions {

base/src/main/java/com/hako/base/di/BaseModules.kt

@@ -1,16 +0,0 @@
-package com.hako.base.di
-
-import androidx.room.Room
-import com.hako.base.BuildConfig
-import com.hako.base.room.BaseDatabase
-import org.koin.dsl.module
-
-val baseModule = module {
-
-    // Room database
-    single { Room.databaseBuilder(get(), BaseDatabase::class.java, BuildConfig.DB_NAME).build() }
-    factory { get<BaseDatabase>().userDao() }
-    factory { get<BaseDatabase>().albumDao() }
-    factory { get<BaseDatabase>().photoDao() }
-
-}

base/src/main/java/com/hako/base/domain/Either.kt

@@ -0,0 +1,33 @@
+package com.hako.base.domain
+
+sealed class Either<out L, out R> {
+
+    data class Left<out L>(val a: L) : Either<L, Nothing>()
+    data class Right<out R>(val b: R) : Either<Nothing, R>()
+
+    val isRight get() = this is Right<R>
+    val isLeft get() = this is Left<L>
+
+    fun <L> left(a: L) = Left(a)
+    fun <R> right(b: R) = Right(b)
+
+    fun either(fnL: (L) -> Any, fnR: (R) -> Any): Any =
+            when (this) {
+                is Left -> fnL(a)
+                is Right -> fnR(b)
+            }
+}
+
+fun <A, B, C> ((A) -> B).c(f: (B) -> C): (A) -> C = {
+    f(this(it))
+}
+
+fun <T, L, R> Either<L, R>.flatMap(fn: (R) -> Either<L, T>): Either<L, T> =
+        when (this) {
+            is Either.Left -> Either.Left(
+                a
+            )
+            is Either.Right -> fn(b)
+        }
+
+fun <T, L, R> Either<L, R>.map(fn: (R) -> (T)): Either<L, T> = this.flatMap(fn.c(::right))

base/src/main/java/com/hako/base/domain/UseCase.kt

@@ -0,0 +1,5 @@
+package com.hako.base.domain
+
+interface UseCase <T> {
+    fun execute(onSuccess: (List<T>) -> Unit, onError: (Throwable) -> Unit, onLoading: () -> Unit)
+}

base/src/main/java/com/hako/base/domain/database/DatabaseClient.kt

@@ -0,0 +1,17 @@
+package com.hako.base.domain.database
+
+import androidx.room.Database
+import androidx.room.RoomDatabase
+import com.hako.base.domain.database.dao.AlbumDao
+import com.hako.base.domain.database.dao.PhotoDao
+import com.hako.base.domain.database.dao.UserDao
+import com.hako.base.domain.database.entities.AlbumEntity
+import com.hako.base.domain.database.entities.PhotoEntity
+import com.hako.base.domain.database.entities.UserEntity
+
+@Database(entities = [UserEntity::class, AlbumEntity::class, PhotoEntity::class], version = 1, exportSchema = false)
+abstract class DatabaseClient : RoomDatabase() {
+    abstract fun userDao(): UserDao
+    abstract fun albumDao(): AlbumDao
+    abstract fun photoDao(): PhotoDao
+}

base/src/main/java/com/hako/base/domain/database/dao/AlbumDao.kt

@@ -1,10 +1,10 @@
-package com.hako.base.room.dao
+package com.hako.base.domain.database.dao
 
 import androidx.room.Dao
 import androidx.room.Insert
 import androidx.room.OnConflictStrategy
 import androidx.room.Query
-import com.hako.base.room.entities.AlbumEntity
+import com.hako.base.domain.database.entities.AlbumEntity
 
 @Dao
 interface AlbumDao {

base/src/main/java/com/hako/base/domain/database/dao/PhotoDao.kt

@@ -1,10 +1,10 @@
-package com.hako.base.room.dao
+package com.hako.base.domain.database.dao
 
 import androidx.room.Dao
 import androidx.room.Insert
 import androidx.room.OnConflictStrategy
 import androidx.room.Query
-import com.hako.base.room.entities.PhotoEntity
+import com.hako.base.domain.database.entities.PhotoEntity
 
 @Dao
 interface PhotoDao {

base/src/main/java/com/hako/base/domain/database/dao/UserDao.kt

@@ -1,10 +1,10 @@
-package com.hako.base.room.dao
+package com.hako.base.domain.database.dao
 
 import androidx.room.Dao
 import androidx.room.Insert
 import androidx.room.OnConflictStrategy
 import androidx.room.Query
-import com.hako.base.room.entities.UserEntity
+import com.hako.base.domain.database.entities.UserEntity
 
 @Dao
 interface UserDao {
@@ -18,6 +18,9 @@ interface UserDao {
     @get:Query("SELECT * FROM ${UserEntity.TABLE_NAME}")
     val all: List<UserEntity>
 
+    @Query("SELECT * FROM ${UserEntity.TABLE_NAME}")
+    fun getAllUsers(): List<UserEntity>
+
     @Query("SELECT COUNT(*) FROM ${UserEntity.TABLE_NAME}")
     fun count(): Int
 

base/src/main/java/com/hako/base/domain/database/entities/Album.kt

@@ -1,4 +1,4 @@
-package com.hako.base.room.entities
+package com.hako.base.domain.database.entities
 
 import androidx.room.Entity
 import androidx.room.Index

base/src/main/java/com/hako/base/domain/database/entities/Photos.kt

@@ -1,4 +1,4 @@
-package com.hako.base.room.entities
+package com.hako.base.domain.database.entities
 
 import androidx.room.Entity
 import androidx.room.Index

base/src/main/java/com/hako/base/domain/database/entities/User.kt

@@ -1,4 +1,4 @@
-package com.hako.base.room.entities
+package com.hako.base.domain.database.entities
 
 import androidx.room.Entity
 import androidx.room.Index

base/src/main/java/com/hako/base/domain/network/RemoteClient.kt

@@ -0,0 +1,35 @@
+package com.hako.base.domain.network
+
+import com.hako.base.BuildConfig
+import okhttp3.OkHttpClient
+import okhttp3.logging.HttpLoggingInterceptor
+import retrofit2.Retrofit
+import retrofit2.adapter.rxjava2.RxJava2CallAdapterFactory
+import retrofit2.converter.gson.GsonConverterFactory
+import timber.log.Timber
+
+class RemoteClient(endpoint: String) {
+    private val logger = HttpLoggingInterceptor(object : HttpLoggingInterceptor.Logger {
+        override fun log(message: String) {
+            Timber.d(message)
+        }
+    }).setLevel(getLoggerLevel())
+
+    private val client = OkHttpClient.Builder()
+        .addInterceptor(logger)
+        .build()
+
+    private val retrofit: Retrofit = Retrofit.Builder()
+        .baseUrl(endpoint)
+        .addConverterFactory(GsonConverterFactory.create())
+        .addCallAdapterFactory(RxJava2CallAdapterFactory.create())
+        .client(client)
+        .build()
+
+    fun <T> getClient(api: Class<T>): T = retrofit.create(api)
+
+    private fun getLoggerLevel() = when (BuildConfig.DEBUG) {
+        true -> HttpLoggingInterceptor.Level.BASIC
+        false -> HttpLoggingInterceptor.Level.NONE
+    }
+}

base/src/main/java/com/hako/base/domain/network/RequestStatus.kt

@@ -0,0 +1,7 @@
+package com.hako.base.domain.network
+
+sealed class RequestStatus {
+    object Ready : RequestStatus()
+    object Loading : RequestStatus()
+    object Errored : RequestStatus()
+}

base/src/main/java/com/hako/base/extensions/LiveDataExtensions.kt

@@ -0,0 +1,13 @@
+package com.hako.base.extensions
+
+import androidx.lifecycle.LifecycleOwner
+import androidx.lifecycle.LiveData
+import androidx.lifecycle.Observer
+
+fun <T> LiveData<T>.observeNonNull(owner: LifecycleOwner, func: (T) -> Unit) {
+    observe(owner, Observer {
+        it?.let {
+            func(it)
+        }
+    })
+}

base/src/main/java/com/hako/base/room/BaseDatabase.kt

@@ -1,17 +0,0 @@
-package com.hako.base.room
-
-import androidx.room.Database
-import androidx.room.RoomDatabase
-import com.hako.base.room.dao.AlbumDao
-import com.hako.base.room.dao.PhotoDao
-import com.hako.base.room.dao.UserDao
-import com.hako.base.room.entities.AlbumEntity
-import com.hako.base.room.entities.PhotoEntity
-import com.hako.base.room.entities.UserEntity
-
-@Database(entities = [UserEntity::class, AlbumEntity::class, PhotoEntity::class], version = 1, exportSchema = false)
-abstract class BaseDatabase : RoomDatabase() {
-    abstract fun userDao(): UserDao
-    abstract fun albumDao(): AlbumDao
-    abstract fun photoDao(): PhotoDao
-}

userlist/src/main/java/com/hako/friendlist/di/UserlistModules.kt

@@ -0,0 +1,17 @@
+package com.hako.friendlist.di
+
+import com.hako.base.domain.network.RemoteClient
+import com.hako.friendlist.domain.datasource.UserlistDatasource
+import com.hako.friendlist.domain.datasource.UserlistRemoteApi
+import com.hako.friendlist.domain.usecase.GetUsers
+import com.hako.friendlist.viewmodel.UserlistViewmodel
+import org.koin.androidx.viewmodel.dsl.viewModel
+import org.koin.dsl.module
+
+val userlistModules = module {
+    factory { get<RemoteClient>().getClient(UserlistRemoteApi::class.java) }
+    factory { UserlistDatasource() }
+    factory { GetUsers(get()) }
+
+    viewModel { UserlistViewmodel() }
+}

userlist/src/main/java/com/hako/friendlist/domain/datasource/UserlistDatasource.kt

@@ -0,0 +1,13 @@
+package com.hako.friendlist.domain.datasource
+
+import com.hako.friendlist.model.User
+import io.reactivex.Single
+import org.koin.core.KoinComponent
+import org.koin.core.get
+
+class UserlistDatasource : KoinComponent, UserlistRemoteApi {
+
+    private val api: UserlistRemoteApi = get()
+
+    override fun getUsers(): Single<List<User>> = api.getUsers()
+}

userlist/src/main/java/com/hako/friendlist/domain/datasource/UserlistRemoteApi.kt

@@ -0,0 +1,11 @@
+package com.hako.friendlist.domain.datasource
+
+import com.hako.friendlist.model.User
+import io.reactivex.Single
+import retrofit2.http.GET
+
+interface UserlistRemoteApi {
+
+    @GET("/users")
+    fun getUsers(): Single<List<User>>
+}

userlist/src/main/java/com/hako/friendlist/domain/usecase/GetUsers.kt

@@ -0,0 +1,43 @@
+package com.hako.friendlist.domain.usecase
+
+import com.hako.base.domain.UseCase
+import com.hako.base.domain.database.dao.UserDao
+import com.hako.friendlist.domain.datasource.UserlistDatasource
+import com.hako.friendlist.model.UserViewable
+import com.hako.friendlist.model.toUserEntity
+import com.hako.friendlist.model.toUserViewable
+import io.reactivex.Single
+import io.reactivex.schedulers.Schedulers
+import org.koin.core.KoinComponent
+import org.koin.core.get
+
+class GetUsers(private val dao: UserDao) : KoinComponent,
+    UseCase<UserViewable> {
+
+    private val api: UserlistDatasource = get()
+
+    override fun execute(
+        onSuccess: (List<UserViewable>) -> Unit,
+        onError: (Throwable) -> Unit,
+        onLoading: () -> Unit
+    ) {
+        Single.fromCallable { dao.getAllUsers() }
+            .subscribeOn(Schedulers.io())
+            .doOnError { onError(it) }
+            .doOnSuccess { dbUsers ->
+                if (dbUsers.isEmpty() || dbUsers.count() == 0) {
+                    api.getUsers()
+                        .doOnSuccess {
+                            dao.saveAll(it.map { user -> user.toUserEntity() })
+                            onSuccess(dao.getAllUsers().map { user -> user.toUserViewable() })
+                        }
+                        .doOnSubscribe { onLoading() }
+                        .subscribeOn(Schedulers.io())
+                        .subscribe({}, { onError(it) })
+                } else {
+                    onSuccess(dbUsers.map { it.toUserViewable() })
+                }
+            }
+            .subscribe()
+    }
+}

userlist/src/main/java/com/hako/friendlist/feature/UserlistFragment.kt

@@ -6,14 +6,20 @@ import android.view.View
 import android.view.ViewGroup
 import androidx.fragment.app.Fragment
 import androidx.recyclerview.widget.LinearLayoutManager
+import com.hako.base.domain.network.RequestStatus
+import com.hako.base.extensions.observeNonNull
 import com.hako.base.extensions.toast
 import com.hako.friendlist.model.UserViewable
+import com.hako.friendlist.viewmodel.UserlistViewmodel
 import com.hako.friendlist.widget.UserlistAdapter
 import com.hako.friendlist_userlist.R
 import kotlinx.android.synthetic.main.fragment_userlist.*
+import org.koin.androidx.viewmodel.ext.android.viewModel
+import timber.log.Timber
 
 class UserlistFragment : Fragment() {
 
+    private val viewModel: UserlistViewmodel by viewModel()
     private val chatAdapter by lazy { UserlistAdapter() }
 
     override fun onCreateView(
@@ -23,37 +29,37 @@ class UserlistFragment : Fragment() {
     override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
         super.onViewCreated(view, savedInstanceState)
         setRecycler()
+        setObservers()
+        viewModel.fetchUsers()
+    }
+
+    private fun setObservers() {
+        viewModel.data.observeNonNull(this) {
+            it.either(::handleFetchError, ::handleFetchSuccess)
+        }
+
+        viewModel.requestStatus.observeNonNull(this) {
+            when (it) {
+                RequestStatus.Ready -> { context?.toast("Ready") }
+                RequestStatus.Loading -> { context?.toast("Loading") }
+                RequestStatus.Errored -> { context?.toast("Errored") }
+            }
+        }
+    }
+
+    private fun handleFetchError(throwable: Throwable) {
+        context?.toast("Could't get data")
+        Timber.e(throwable)
+    }
+
+    private fun handleFetchSuccess(users: List<UserViewable>) {
+        chatAdapter.addAll(users)
     }
 
     private fun setRecycler() {
         fragment_userlist_recycler_container.apply {
             layoutManager = LinearLayoutManager(context)
             adapter = chatAdapter.apply {
-                addAll(
-                    listOf(
-                        UserViewable(1, "Carlos Martinez", "carlitos"),
-                        UserViewable(2, "Carlos Martinez", "carlitos"),
-                        UserViewable(3, "Carlos Martinez", "carlitos"),
-                        UserViewable(4, "Carlos Martinez", "carlitos"),
-                        UserViewable(5, "Carlos Martinez", "carlitos"),
-                        UserViewable(6, "Carlos Martinez", "carlitos"),
-                        UserViewable(7, "Carlos Martinez", "carlitos"),
-                        UserViewable(8, "Carlos Martinez", "carlitos"),
-                        UserViewable(9, "Carlos Martinez", "carlitos"),
-                        UserViewable(10, "Carlos Martinez", "carlitos"),
-                        UserViewable(11, "Carlos Martinez", "carlitos"),
-                        UserViewable(12, "Carlos Martinez", "carlitos"),
-                        UserViewable(13, "Carlos Martinez", "carlitos"),
-                        UserViewable(14, "Carlos Martinez", "carlitos"),
-                        UserViewable(15, "Carlos Martinez", "carlitos"),
-                        UserViewable(16, "Carlos Martinez", "carlitos"),
-                        UserViewable(17, "Carlos Martinez", "carlitos"),
-                        UserViewable(18, "Carlos Martinez", "carlitos"),
-                        UserViewable(19, "Carlos Martinez", "carlitos"),
-                        UserViewable(20, "Carlos Martinez", "carlitos")
-                    )
-                )
-
                 onItemClick = {
                     context.toast(it.realName)
                 }

userlist/src/main/java/com/hako/friendlist/model/UserModels.kt

@@ -2,7 +2,7 @@ package com.hako.friendlist.model
 
 import android.os.Parcelable
 import com.google.gson.annotations.SerializedName
-import com.hako.base.room.entities.UserEntity
+import com.hako.base.domain.database.entities.UserEntity
 import kotlinx.android.parcel.Parcelize
 
 @Parcelize
@@ -20,9 +20,9 @@ data class UserViewable(
     val realName: String,
     val userName: String,
     var isFavorite: Boolean = false
-) {
-    fun User.toUserViewable() = UserViewable(this.id, this.realName, this.userName)
+)
+
+fun User.toUserEntity() = UserEntity(this.id, this.realName, this.userName, this.email, this.phone, this.website)
 
 fun UserEntity.toUserViewable() = UserViewable(this.id, this.realName, this.userName)
-}
 

userlist/src/main/java/com/hako/friendlist/viewmodel/UserlistViewmodel.kt

@@ -0,0 +1,36 @@
+package com.hako.friendlist.viewmodel
+
+import androidx.lifecycle.MutableLiveData
+import androidx.lifecycle.ViewModel
+import com.hako.base.domain.network.RequestStatus
+import com.hako.base.domain.network.RequestStatus.Ready
+import com.hako.base.domain.network.RequestStatus.Loading
+import com.hako.base.domain.network.RequestStatus.Errored
+import com.hako.base.domain.Either
+import com.hako.friendlist.domain.usecase.GetUsers
+import com.hako.friendlist.model.UserViewable
+import org.koin.core.KoinComponent
+import org.koin.core.get
+
+class UserlistViewmodel : ViewModel(), KoinComponent {
+
+    val data = MutableLiveData<Either<Throwable, List<UserViewable>>>()
+    val requestStatus = MutableLiveData<RequestStatus>()
+
+    private val getUsers: GetUsers = get()
+
+    fun fetchUsers() {
+        getUsers.execute(
+            onSuccess = {
+                requestStatus.postValue(Ready)
+                data.postValue(Either.Right(it))
+            },
+            onLoading = {
+                requestStatus.postValue(Loading)
+            },
+            onError = {
+                requestStatus.postValue(Errored)
+                data.postValue(Either.Left(it))
+            })
+    }
+}