refactor(api): adopt EitherNet

android/src/main/kotlin/dev/msfjarvis/claw/android/injection/ApiModule.kt

@@ -1,6 +1,8 @@
 package dev.msfjarvis.claw.android.injection
 
 import com.jakewharton.retrofit2.converter.kotlinx.serialization.asConverterFactory
+import com.slack.eithernet.ApiResultCallAdapterFactory
+import com.slack.eithernet.ApiResultConverterFactory
 import dagger.Module
 import dagger.Provides
 import dagger.hilt.InstallIn
@@ -26,7 +28,9 @@ object ApiModule {
     return Retrofit.Builder()
       .client(client)
       .baseUrl(LobstersApi.BASE_URL)
+      .addConverterFactory(ApiResultConverterFactory)
       .addConverterFactory(json.asConverterFactory(contentType))
+      .addCallAdapterFactory(ApiResultCallAdapterFactory)
       .build()
   }
 

android/src/main/kotlin/dev/msfjarvis/claw/android/paging/LobstersPagingSource.kt

@@ -2,11 +2,14 @@ package dev.msfjarvis.claw.android.paging
 
 import androidx.paging.PagingSource
 import androidx.paging.PagingState
+import com.slack.eithernet.ApiResult.Failure
+import com.slack.eithernet.ApiResult.Success
 import dagger.assisted.Assisted
 import dagger.assisted.AssistedFactory
 import dagger.assisted.AssistedInject
 import dev.msfjarvis.claw.android.injection.IODispatcher
 import dev.msfjarvis.claw.model.LobstersPost
+import java.io.IOException
 import kotlinx.coroutines.CoroutineDispatcher
 import kotlinx.coroutines.withContext
 
@@ -17,19 +20,19 @@ constructor(
   @IODispatcher private val ioDispatcher: CoroutineDispatcher,
 ) : PagingSource<Int, LobstersPost>() {
 
-  @Suppress("TooGenericExceptionCaught") // Intentional
   override suspend fun load(params: LoadParams<Int>): LoadResult<Int, LobstersPost> {
-    return try {
-      val page = params.key ?: 1
-      val posts = withContext(ioDispatcher) { remoteFetcher.getItemsAtPage(page) }
-
-      LoadResult.Page(
-        data = posts,
-        prevKey = if (page == 1) null else page - 1,
-        nextKey = page.plus(1)
-      )
-    } catch (e: Exception) {
-      LoadResult.Error(e)
+    val page = params.key ?: 1
+    return when (val result = withContext(ioDispatcher) { remoteFetcher.getItemsAtPage(page) }) {
+      is Success ->
+        LoadResult.Page(
+          data = result.value,
+          prevKey = if (page == 1) null else page - 1,
+          nextKey = page.plus(1)
+        )
+      is Failure.NetworkFailure -> LoadResult.Error(result.error)
+      is Failure.UnknownFailure -> LoadResult.Error(result.error)
+      is Failure.HttpFailure,
+      is Failure.ApiFailure -> LoadResult.Error(IOException("API returned an invalid response"))
     }
   }
 

android/src/main/kotlin/dev/msfjarvis/claw/android/paging/RemoteFetcher.kt

@@ -1,6 +1,8 @@
 package dev.msfjarvis.claw.android.paging
 
+import com.slack.eithernet.ApiResult
+
 /** SAM interface to abstract over a remote API that fetches paginated content. */
 fun interface RemoteFetcher<T> {
-  suspend fun getItemsAtPage(page: Int): List<T>
+  suspend fun getItemsAtPage(page: Int): ApiResult<List<T>, Unit>
 }

android/src/main/kotlin/dev/msfjarvis/claw/android/viewmodel/ClawViewModel.kt

@@ -4,12 +4,15 @@ import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
 import androidx.paging.Pager
 import androidx.paging.PagingConfig
+import com.slack.eithernet.ApiResult.Failure
+import com.slack.eithernet.ApiResult.Success
 import dagger.hilt.android.lifecycle.HiltViewModel
 import dev.msfjarvis.claw.android.injection.IODispatcher
 import dev.msfjarvis.claw.android.paging.LobstersPagingSource
 import dev.msfjarvis.claw.android.ui.toLocalDateTime
 import dev.msfjarvis.claw.api.LobstersApi
 import dev.msfjarvis.claw.database.local.SavedPost
+import java.io.IOException
 import java.time.Month
 import javax.inject.Inject
 import kotlinx.coroutines.CoroutineDispatcher
@@ -73,12 +76,28 @@ constructor(
 
   suspend fun getPostComments(postId: String) =
     withContext(ioDispatcher) {
-      val details = api.getPostDetails(postId)
+      val details =
+        when (val result = api.getPostDetails(postId)) {
+          is Success -> result.value
+          is Failure.NetworkFailure -> throw result.error
+          is Failure.UnknownFailure -> throw result.error
+          is Failure.HttpFailure,
+          is Failure.ApiFailure -> throw IOException("API returned an invalid response")
+        }
       val extendedDetails = postDetailsRepository.getExtendedDetails(details)
       extendedDetails
     }
 
-  suspend fun getUserProfile(username: String) = withContext(ioDispatcher) { api.getUser(username) }
+  suspend fun getUserProfile(username: String) =
+    withContext(ioDispatcher) {
+      when (val result = api.getUser(username)) {
+        is Success -> result.value
+        is Failure.NetworkFailure -> throw result.error
+        is Failure.UnknownFailure -> throw result.error
+        is Failure.HttpFailure,
+        is Failure.ApiFailure -> throw IOException("API returned an invalid response")
+      }
+    }
 
   fun refreshHottestPosts() {
     hottestPostsPagingSource?.invalidate()

android/src/main/kotlin/dev/msfjarvis/claw/android/work/SavedPostUpdaterWorker.kt

@@ -4,13 +4,13 @@ import android.content.Context
 import androidx.hilt.work.HiltWorker
 import androidx.work.CoroutineWorker
 import androidx.work.WorkerParameters
+import com.slack.eithernet.ApiResult
 import dagger.assisted.Assisted
 import dagger.assisted.AssistedInject
 import dev.msfjarvis.claw.android.viewmodel.SavedPostsRepository
 import dev.msfjarvis.claw.api.LobstersApi
 import dev.msfjarvis.claw.common.posts.toDbModel
 import kotlinx.coroutines.CoroutineScope
-import kotlinx.coroutines.ExperimentalCoroutinesApi
 import kotlinx.coroutines.Job
 import kotlinx.coroutines.async
 import kotlinx.coroutines.awaitAll
@@ -23,7 +23,6 @@ import kotlinx.coroutines.flow.first
  * and for new-enough posts that are still getting comments to have an accurate one.
  */
 @Suppress("DEPRECATION") // We're being nasty
-@OptIn(ExperimentalCoroutinesApi::class)
 @HiltWorker
 class SavedPostUpdaterWorker
 @AssistedInject
@@ -39,8 +38,8 @@ constructor(
       .map { post ->
         CoroutineScope(coroutineContext + Job()).async {
           val details = runCatching { lobstersApi.getPostDetails(post.shortId) }.getOrNull()
-          if (details != null) {
-            savedPostsRepository.savePost(details.toDbModel())
+          if (details is ApiResult.Success) {
+            savedPostsRepository.savePost(details.value.toDbModel())
           }
         }
       }

api/build.gradle.kts

@@ -8,6 +8,7 @@ plugins {
 dependencies {
   api(projects.model)
   api(libs.retrofit.lib)
+  api(libs.eithernet)
   implementation(libs.kotlinx.serialization.core)
   testImplementation(libs.kotlinx.coroutines.core)
   testImplementation(kotlin("test-junit"))

api/src/main/kotlin/dev/msfjarvis/claw/api/LobstersApi.kt

@@ -1,5 +1,6 @@
 package dev.msfjarvis.claw.api
 
+import com.slack.eithernet.ApiResult
 import dev.msfjarvis.claw.model.LobstersPost
 import dev.msfjarvis.claw.model.LobstersPostDetails
 import dev.msfjarvis.claw.model.User
@@ -10,14 +11,17 @@ import retrofit2.http.Query
 /** Simple interface defining an API for lobste.rs */
 interface LobstersApi {
 
-  @GET("hottest.json") suspend fun getHottestPosts(@Query("page") page: Int): List<LobstersPost>
+  @GET("hottest.json")
+  suspend fun getHottestPosts(@Query("page") page: Int): ApiResult<List<LobstersPost>, Unit>
 
-  @GET("newest.json") suspend fun getNewestPosts(@Query("page") page: Int): List<LobstersPost>
+  @GET("newest.json")
+  suspend fun getNewestPosts(@Query("page") page: Int): ApiResult<List<LobstersPost>, Unit>
 
   @GET("s/{postId}.json")
-  suspend fun getPostDetails(@Path("postId") postId: String): LobstersPostDetails
+  suspend fun getPostDetails(@Path("postId") postId: String): ApiResult<LobstersPostDetails, Unit>
 
-  @GET("u/{username}.json") suspend fun getUser(@Path("username") username: String): User
+  @GET("u/{username}.json")
+  suspend fun getUser(@Path("username") username: String): ApiResult<User, Unit>
 
   companion object {
     const val BASE_URL = "https://lobste.rs"

gradle/libs.versions.toml

@@ -67,6 +67,7 @@ crux = "com.chimbori.crux:crux:3.9.1"
 dagger-hilt-android = { module = "com.google.dagger:hilt-android", version.ref = "dagger" }
 dagger-hilt-compiler = { module = "com.google.dagger:hilt-compiler", version.ref = "dagger" }
 dagger-hilt-core = { module = "com.google.dagger:hilt-core", version.ref = "dagger" }
+eithernet = "com.slack.eithernet:eithernet:1.2.1"
 javapoet = "com.squareup:javapoet:1.13.0"
 jsoup = "org.jsoup:jsoup:1.15.3"
 kotlinx-coroutines-core = { module = "org.jetbrains.kotlinx:kotlinx-coroutines-core", version.ref = "coroutines" }