Major code refactoring

Main goals are:
1. Ability to use mocks in unit tests instead of
having to setup mock web server as if it was an
integration test.
2. Cache Retrofit services in memory
3. Make it easier to read
4. Use OptIn where possible instead of propagating
Experimental* annotations everywhere

app/src/main/java/gq/kirmanak/mealient/data/auth/AuthRepo.kt

@@ -7,7 +7,11 @@ interface AuthRepo {
 
     suspend fun getBaseUrl(): String?
 
-    suspend fun getToken(): String?
+    suspend fun requireBaseUrl(): String
+
+    suspend fun getAuthHeader(): String?
+
+    suspend fun requireAuthHeader(): String
 
     fun authenticationStatuses(): Flow<Boolean>
 

app/src/main/java/gq/kirmanak/mealient/data/auth/AuthStorage.kt

@@ -3,13 +3,13 @@ package gq.kirmanak.mealient.data.auth
 import kotlinx.coroutines.flow.Flow
 
 interface AuthStorage {
-    fun storeAuthData(token: String, baseUrl: String)
+    fun storeAuthData(authHeader: String, baseUrl: String)
 
     suspend fun getBaseUrl(): String?
 
-    suspend fun getToken(): String?
+    suspend fun getAuthHeader(): String?
 
-    fun tokenObservable(): Flow<String?>
+    fun authHeaderObservable(): Flow<String?>
 
     fun clearAuthData()
 }

app/src/main/java/gq/kirmanak/mealient/data/auth/impl/AuthDataSourceImpl.kt

@@ -3,20 +3,18 @@ package gq.kirmanak.mealient.data.auth.impl
 import gq.kirmanak.mealient.data.auth.AuthDataSource
 import gq.kirmanak.mealient.data.auth.impl.AuthenticationError.*
 import gq.kirmanak.mealient.data.impl.ErrorDetail
-import gq.kirmanak.mealient.data.impl.RetrofitBuilder
 import gq.kirmanak.mealient.data.impl.util.decodeErrorBodyOrNull
+import gq.kirmanak.mealient.data.network.ServiceFactory
 import kotlinx.coroutines.CancellationException
-import kotlinx.serialization.ExperimentalSerializationApi
 import kotlinx.serialization.SerializationException
 import kotlinx.serialization.json.Json
 import retrofit2.HttpException
-import retrofit2.create
+import retrofit2.Response
 import timber.log.Timber
 import javax.inject.Inject
 
-@ExperimentalSerializationApi
 class AuthDataSourceImpl @Inject constructor(
-    private val retrofitBuilder: RetrofitBuilder,
+    private val authServiceFactory: ServiceFactory<AuthService>,
     private val json: Json,
 ) : AuthDataSource {
 
@@ -26,31 +24,37 @@ class AuthDataSourceImpl @Inject constructor(
         baseUrl: String
     ): String {
         Timber.v("authenticate() called with: username = $username, password = $password, baseUrl = $baseUrl")
-        val authService = retrofitBuilder.buildRetrofit(baseUrl).create<AuthService>()
-
-        val accessToken = runCatching {
-            val response = authService.getToken(username, password)
-            Timber.d("authenticate() response is $response")
-            if (response.isSuccessful) {
-                checkNotNull(response.body()).accessToken
-            } else {
-                val cause = HttpException(response)
-                val errorDetail: ErrorDetail? = response.decodeErrorBodyOrNull(json)
-                throw when (errorDetail?.detail) {
-                    "Unauthorized" -> Unauthorized(cause)
-                    else -> NotMealie(cause)
-                }
-            }
-        }.onFailure {
-            Timber.e(it, "authenticate: getToken failed")
-            throw when (it) {
-                is CancellationException, is AuthenticationError -> it
-                is SerializationException, is IllegalStateException -> NotMealie(it)
-                else -> NoServerConnection(it)
-            }
-        }.getOrThrow()
-
+        val authService = authServiceFactory.provideService(baseUrl)
+        val response = sendRequest(authService, username, password)
+        val accessToken = parseToken(response)
         Timber.v("authenticate() returned: $accessToken")
         return accessToken
     }
+
+    private suspend fun sendRequest(
+        authService: AuthService,
+        username: String,
+        password: String
+    ): Response<GetTokenResponse> = try {
+        authService.getToken(username, password)
+    } catch (e: Throwable) {
+        throw when (e) {
+            is CancellationException -> e
+            is SerializationException -> NotMealie(e)
+            else -> NoServerConnection(e)
+        }
+    }
+
+    private fun parseToken(
+        response: Response<GetTokenResponse>
+    ): String = if (response.isSuccessful) {
+        response.body()?.accessToken ?: throw NotMealie(NullPointerException("Body is null"))
+    } else {
+        val cause = HttpException(response)
+        val errorDetail: ErrorDetail? = response.decodeErrorBodyOrNull(json)
+        throw when (errorDetail?.detail) {
+            "Unauthorized" -> Unauthorized(cause)
+            else -> NotMealie(cause)
+        }
+    }
 }

app/src/main/java/gq/kirmanak/mealient/data/auth/impl/AuthOkHttpInterceptor.kt

@@ -1,29 +0,0 @@
-package gq.kirmanak.mealient.data.auth.impl
-
-import gq.kirmanak.mealient.data.auth.AuthStorage
-import kotlinx.coroutines.runBlocking
-import okhttp3.Interceptor
-import okhttp3.Response
-import timber.log.Timber
-import javax.inject.Inject
-
-const val AUTHORIZATION_HEADER = "Authorization"
-
-class AuthOkHttpInterceptor @Inject constructor(
-    private val authStorage: AuthStorage
-) : Interceptor {
-    override fun intercept(chain: Interceptor.Chain): Response {
-        Timber.v("intercept() called with: chain = $chain")
-        val token = runBlocking { authStorage.getToken() }
-        Timber.d("intercept: token = $token")
-        val request = if (token.isNullOrBlank()) {
-            chain.request()
-        } else {
-            chain.request()
-                .newBuilder()
-                .addHeader(AUTHORIZATION_HEADER, "Bearer $token")
-                .build()
-        }
-        return chain.proceed(request)
-    }
-}

app/src/main/java/gq/kirmanak/mealient/data/auth/impl/AuthRepoImpl.kt

@@ -14,8 +14,9 @@ import javax.inject.Inject
 
 class AuthRepoImpl @Inject constructor(
     private val dataSource: AuthDataSource,
-    private val storage: AuthStorage
+    private val storage: AuthStorage,
 ) : AuthRepo {
+
     override suspend fun authenticate(
         username: String,
         password: String,
@@ -24,20 +25,23 @@ class AuthRepoImpl @Inject constructor(
         Timber.v("authenticate() called with: username = $username, password = $password, baseUrl = $baseUrl")
         val url = parseBaseUrl(baseUrl)
         val accessToken = dataSource.authenticate(username, password, url)
-        Timber.d("authenticate result is $accessToken")
-        storage.storeAuthData(accessToken, url)
+        Timber.d("authenticate result is \"$accessToken\"")
+        storage.storeAuthData(AUTH_HEADER_FORMAT.format(accessToken), url)
     }
 
     override suspend fun getBaseUrl(): String? = storage.getBaseUrl()
 
-    override suspend fun getToken(): String? {
-        Timber.v("getToken() called")
-        return storage.getToken()
-    }
+    override suspend fun requireBaseUrl(): String =
+        checkNotNull(getBaseUrl()) { "Base URL is null when it was required" }
+
+    override suspend fun getAuthHeader(): String? = storage.getAuthHeader()
+
+    override suspend fun requireAuthHeader(): String =
+        checkNotNull(getAuthHeader()) { "Auth header is null when it was required" }
 
     override fun authenticationStatuses(): Flow<Boolean> {
         Timber.v("authenticationStatuses() called")
-        return storage.tokenObservable().map { it != null }
+        return storage.authHeaderObservable().map { it != null }
     }
 
     override fun logout() {
@@ -57,4 +61,7 @@ class AuthRepoImpl @Inject constructor(
         throw MalformedUrl(e)
     }
 
+    companion object {
+        private const val AUTH_HEADER_FORMAT = "Bearer %s"
+    }
 }

app/src/main/java/gq/kirmanak/mealient/data/auth/impl/AuthService.kt

@@ -11,9 +11,5 @@ interface AuthService {
     suspend fun getToken(
         @Field("username") username: String,
         @Field("password") password: String,
-        @Field("grant_type") grantType: String? = null,
-        @Field("scope") scope: String? = null,
-        @Field("client_id") clientId: String? = null,
-        @Field("client_secret") clientSecret: String? = null
     ): Response<GetTokenResponse>
 }

app/src/main/java/gq/kirmanak/mealient/data/auth/impl/AuthStorageImpl.kt

@@ -1,29 +1,28 @@
 package gq.kirmanak.mealient.data.auth.impl
 
 import android.content.SharedPreferences
+import androidx.core.content.edit
 import gq.kirmanak.mealient.data.auth.AuthStorage
 import gq.kirmanak.mealient.data.impl.util.changesFlow
 import gq.kirmanak.mealient.data.impl.util.getStringOrNull
-import kotlinx.coroutines.ExperimentalCoroutinesApi
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.map
 import timber.log.Timber
 import javax.inject.Inject
 
-private const val TOKEN_KEY = "AUTH_TOKEN"
+private const val AUTH_HEADER_KEY = "AUTH_TOKEN"
 private const val BASE_URL_KEY = "BASE_URL"
 
-@ExperimentalCoroutinesApi
 class AuthStorageImpl @Inject constructor(
     private val sharedPreferences: SharedPreferences
 ) : AuthStorage {
 
-    override fun storeAuthData(token: String, baseUrl: String) {
-        Timber.v("storeAuthData() called with: token = $token, baseUrl = $baseUrl")
-        sharedPreferences.edit()
-            .putString(TOKEN_KEY, token)
-            .putString(BASE_URL_KEY, baseUrl)
-            .apply()
+    override fun storeAuthData(authHeader: String, baseUrl: String) {
+        Timber.v("storeAuthData() called with: authHeader = $authHeader, baseUrl = $baseUrl")
+        sharedPreferences.edit {
+            putString(AUTH_HEADER_KEY, authHeader)
+            putString(BASE_URL_KEY, baseUrl)
+        }
     }
 
     override suspend fun getBaseUrl(): String? {
@@ -32,23 +31,23 @@ class AuthStorageImpl @Inject constructor(
         return baseUrl
     }
 
-    override suspend fun getToken(): String? {
-        Timber.v("getToken() called")
-        val token = sharedPreferences.getStringOrNull(TOKEN_KEY)
-        Timber.d("getToken: token is $token")
+    override suspend fun getAuthHeader(): String? {
+        Timber.v("getAuthHeader() called")
+        val token = sharedPreferences.getStringOrNull(AUTH_HEADER_KEY)
+        Timber.d("getAuthHeader: header is \"$token\"")
         return token
     }
 
-    override fun tokenObservable(): Flow<String?> {
-        Timber.v("tokenObservable() called")
-        return sharedPreferences.changesFlow().map { it.first.getStringOrNull(TOKEN_KEY) }
+    override fun authHeaderObservable(): Flow<String?> {
+        Timber.v("authHeaderObservable() called")
+        return sharedPreferences.changesFlow().map { it.first.getStringOrNull(AUTH_HEADER_KEY) }
     }
 
     override fun clearAuthData() {
         Timber.v("clearAuthData() called")
-        sharedPreferences.edit()
-            .remove(TOKEN_KEY)
-            .remove(BASE_URL_KEY)
-            .apply()
+        sharedPreferences.edit {
+            remove(AUTH_HEADER_KEY)
+            remove(BASE_URL_KEY)
+        }
     }
-}
+}

app/src/main/java/gq/kirmanak/mealient/data/auth/impl/GetTokenResponse.kt

@@ -4,7 +4,4 @@ import kotlinx.serialization.SerialName
 import kotlinx.serialization.Serializable
 
 @Serializable
-data class GetTokenResponse(
-    @SerialName("access_token") val accessToken: String,
-    @SerialName("token_type") val tokenType: String
-)
+data class GetTokenResponse(@SerialName("access_token") val accessToken: String)

app/src/main/java/gq/kirmanak/mealient/data/impl/RetrofitBuilder.kt

@@ -9,11 +9,12 @@ import retrofit2.Retrofit
 import timber.log.Timber
 import javax.inject.Inject
 
-@ExperimentalSerializationApi
 class RetrofitBuilder @Inject constructor(
     private val okHttpClient: OkHttpClient,
     private val json: Json
 ) {
+
+    @OptIn(ExperimentalSerializationApi::class)
     fun buildRetrofit(baseUrl: String): Retrofit {
         Timber.v("buildRetrofit() called with: baseUrl = $baseUrl")
         val contentType = "application/json".toMediaType()

app/src/main/java/gq/kirmanak/mealient/data/impl/util/NetworkExtensions.kt

@@ -7,11 +7,10 @@ import retrofit2.Response
 import timber.log.Timber
 import java.io.InputStream
 
-@ExperimentalSerializationApi
 inline fun <T, reified R> Response<T>.decodeErrorBodyOrNull(json: Json): R? =
     errorBody()?.byteStream()?.let { json.decodeFromStreamOrNull<R>(it) }
 
-@ExperimentalSerializationApi
+@OptIn(ExperimentalSerializationApi::class)
 inline fun <reified T> Json.decodeFromStreamOrNull(stream: InputStream): T? =
     runCatching { decodeFromStream<T>(stream) }
         .onFailure { Timber.e(it, "decodeFromStreamOrNull: can't decode") }

app/src/main/java/gq/kirmanak/mealient/data/impl/util/SharedPrefExtensions.kt

@@ -17,7 +17,7 @@ suspend fun SharedPreferences.getStringOrNull(key: String) =
 suspend fun SharedPreferences.getBooleanOrFalse(key: String) =
     withContext(Dispatchers.IO) { getBoolean(key, false) }
 
-@ExperimentalCoroutinesApi
+@OptIn(ExperimentalCoroutinesApi::class)
 fun SharedPreferences.changesFlow(): Flow<Pair<SharedPreferences, String?>> = callbackFlow {
     val listener = SharedPreferences.OnSharedPreferenceChangeListener { prefs, key ->
         Timber.v("watchChanges: listener called with key $key")

app/src/main/java/gq/kirmanak/mealient/data/network/RetrofitServiceFactory.kt

@@ -0,0 +1,29 @@
+package gq.kirmanak.mealient.data.network
+
+import gq.kirmanak.mealient.data.impl.RetrofitBuilder
+import timber.log.Timber
+
+inline fun <reified T> RetrofitBuilder.createServiceFactory() =
+    RetrofitServiceFactory(T::class.java, this)
+
+class RetrofitServiceFactory<T>(
+    private val serviceClass: Class<T>,
+    private val retrofitBuilder: RetrofitBuilder,
+) : ServiceFactory<T> {
+
+    private val cache: MutableMap<String, T> = mutableMapOf()
+
+    @Synchronized
+    override fun provideService(baseUrl: String): T {
+        Timber.v("provideService() called with: baseUrl = $baseUrl, class = ${serviceClass.simpleName}")
+        val cached = cache[baseUrl]
+        return if (cached == null) {
+            Timber.d("provideService: cache is empty, creating new")
+            val new = retrofitBuilder.buildRetrofit(baseUrl).create(serviceClass)
+            cache[baseUrl] = new
+            new
+        } else {
+            cached
+        }
+    }
+}

app/src/main/java/gq/kirmanak/mealient/data/network/ServiceFactory.kt

@@ -0,0 +1,6 @@
+package gq.kirmanak.mealient.data.network
+
+interface ServiceFactory<T> {
+
+    fun provideService(baseUrl: String): T
+}

app/src/main/java/gq/kirmanak/mealient/data/recipes/impl/RecipeRepoImpl.kt

@@ -12,7 +12,7 @@ import kotlinx.coroutines.CancellationException
 import timber.log.Timber
 import javax.inject.Inject
 
-@ExperimentalPagingApi
+@OptIn(ExperimentalPagingApi::class)
 class RecipeRepoImpl @Inject constructor(
     private val mediator: RecipesRemoteMediator,
     private val storage: RecipeStorage,

app/src/main/java/gq/kirmanak/mealient/data/recipes/impl/RecipesRemoteMediator.kt

@@ -11,7 +11,7 @@ import kotlinx.coroutines.CancellationException
 import timber.log.Timber
 import javax.inject.Inject
 
-@ExperimentalPagingApi
+@OptIn(ExperimentalPagingApi::class)
 class RecipesRemoteMediator @Inject constructor(
     private val storage: RecipeStorage,
     private val network: RecipeDataSource,

app/src/main/java/gq/kirmanak/mealient/data/recipes/network/RecipeDataSourceImpl.kt

@@ -1,50 +1,35 @@
 package gq.kirmanak.mealient.data.recipes.network
 
 import gq.kirmanak.mealient.data.auth.AuthRepo
-import gq.kirmanak.mealient.data.impl.RetrofitBuilder
+import gq.kirmanak.mealient.data.network.ServiceFactory
 import gq.kirmanak.mealient.data.recipes.network.response.GetRecipeResponse
 import gq.kirmanak.mealient.data.recipes.network.response.GetRecipeSummaryResponse
-import kotlinx.serialization.ExperimentalSerializationApi
 import timber.log.Timber
 import javax.inject.Inject
 
-@ExperimentalSerializationApi
 class RecipeDataSourceImpl @Inject constructor(
     private val authRepo: AuthRepo,
-    private val retrofitBuilder: RetrofitBuilder
+    private val recipeServiceFactory: ServiceFactory<RecipeService>,
 ) : RecipeDataSource {
-    private var _recipeService: RecipeService? = null
 
     override suspend fun requestRecipes(start: Int, limit: Int): List<GetRecipeSummaryResponse> {
         Timber.v("requestRecipes() called with: start = $start, limit = $limit")
-        val service: RecipeService = getRecipeService()
-        val recipeSummary = service.getRecipeSummary(start, limit)
+        val recipeSummary = getRecipeService().getRecipeSummary(start, limit, getToken())
         Timber.v("requestRecipes() returned: $recipeSummary")
         return recipeSummary
     }
 
     override suspend fun requestRecipeInfo(slug: String): GetRecipeResponse {
         Timber.v("requestRecipeInfo() called with: slug = $slug")
-        val service: RecipeService = getRecipeService()
-        val recipeInfo = service.getRecipe(slug)
+        val recipeInfo = getRecipeService().getRecipe(slug, getToken())
         Timber.v("requestRecipeInfo() returned: $recipeInfo")
         return recipeInfo
     }
 
     private suspend fun getRecipeService(): RecipeService {
         Timber.v("getRecipeService() called")
-        val cachedService: RecipeService? = _recipeService
-        val service: RecipeService = if (cachedService == null) {
-            val baseUrl = checkNotNull(authRepo.getBaseUrl()) { "Base url is null" }
-            val token = checkNotNull(authRepo.getToken()) { "Token is null" }
-            Timber.d("requestRecipes: baseUrl = $baseUrl, token = $token")
-            val retrofit = retrofitBuilder.buildRetrofit(baseUrl)
-            val createdService = retrofit.create(RecipeService::class.java)
-            _recipeService = createdService
-            createdService
-        } else {
-            cachedService
-        }
-        return service
+        return recipeServiceFactory.provideService(authRepo.requireBaseUrl())
     }
-}
+
+    private suspend fun getToken(): String = authRepo.requireAuthHeader()
+}

app/src/main/java/gq/kirmanak/mealient/data/recipes/network/RecipeService.kt

@@ -3,6 +3,7 @@ package gq.kirmanak.mealient.data.recipes.network
 import gq.kirmanak.mealient.data.recipes.network.response.GetRecipeResponse
 import gq.kirmanak.mealient.data.recipes.network.response.GetRecipeSummaryResponse
 import retrofit2.http.GET
+import retrofit2.http.Header
 import retrofit2.http.Path
 import retrofit2.http.Query
 
@@ -10,11 +11,13 @@ interface RecipeService {
     @GET("/api/recipes/summary")
     suspend fun getRecipeSummary(
         @Query("start") start: Int,
-        @Query("limit") limit: Int
+        @Query("limit") limit: Int,
+        @Header("Authorization") authHeader: String?,
     ): List<GetRecipeSummaryResponse>
 
     @GET("/api/recipes/{recipe_slug}")
     suspend fun getRecipe(
-        @Path("recipe_slug") recipeSlug: String
+        @Path("recipe_slug") recipeSlug: String,
+        @Header("Authorization") authHeader: String?,
     ): GetRecipeResponse
 }