refactor(android): switch to DispatcherProvider

android/build.gradle.kts

@@ -41,6 +41,7 @@ dependencies {
   kapt(libs.dagger.hilt.compiler)
   implementation(projects.api)
   implementation(projects.common)
+  implementation(projects.coroutineUtils)
   implementation(projects.database)
   implementation(projects.metadataExtractor)
   implementation(projects.model)

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

@@ -0,0 +1,41 @@
+package dev.msfjarvis.claw.android.injection
+
+import dagger.Binds
+import dagger.Module
+import dagger.Provides
+import dagger.hilt.InstallIn
+import dagger.hilt.components.SingletonComponent
+import dev.msfjarvis.claw.util.coroutines.DefaultDispatcherProvider
+import dev.msfjarvis.claw.util.coroutines.DispatcherProvider
+import javax.inject.Qualifier
+import kotlinx.coroutines.CoroutineDispatcher
+
+@Module
+@InstallIn(SingletonComponent::class)
+abstract class CoroutineDispatcherModule {
+
+  @Binds abstract fun DefaultDispatcherProvider.bind(): DispatcherProvider
+
+  companion object {
+    @[Provides IODispatcher]
+    fun provideIODispatcher(dispatcherProvider: DispatcherProvider): CoroutineDispatcher {
+      return dispatcherProvider.io()
+    }
+
+    @[Provides DatabaseDispatcher]
+    fun provideDatabaseDispatcher(dispatcherProvider: DispatcherProvider): CoroutineDispatcher {
+      return dispatcherProvider.database()
+    }
+
+    @[Provides MainDispatcher]
+    fun provideMainDispatcher(dispatcherProvider: DispatcherProvider): CoroutineDispatcher {
+      return dispatcherProvider.main()
+    }
+  }
+}
+
+@Qualifier @Retention(AnnotationRetention.RUNTIME) annotation class DatabaseDispatcher
+
+@Qualifier @Retention(AnnotationRetention.RUNTIME) annotation class MainDispatcher
+
+@Qualifier @Retention(AnnotationRetention.RUNTIME) annotation class IODispatcher

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

@@ -3,17 +3,18 @@ package dev.msfjarvis.claw.android.paging
 import androidx.paging.PagingSource
 import androidx.paging.PagingState
 import dev.msfjarvis.claw.model.LobstersPost
-import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.CoroutineDispatcher
 import kotlinx.coroutines.withContext
 
 class LobstersPagingSource(
   private val getMorePosts: suspend (Int) -> List<LobstersPost>,
+  private val ioDispatcher: CoroutineDispatcher,
 ) : PagingSource<Int, LobstersPost>() {
 
   override suspend fun load(params: LoadParams<Int>): LoadResult<Int, LobstersPost> {
     return try {
       val page = params.key ?: 1
-      val posts = withContext(Dispatchers.IO) { getMorePosts(page) }
+      val posts = withContext(ioDispatcher) { getMorePosts(page) }
 
       LoadResult.Page(
         data = posts,

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

@@ -5,12 +5,13 @@ import androidx.lifecycle.viewModelScope
 import androidx.paging.Pager
 import androidx.paging.PagingConfig
 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 javax.inject.Inject
-import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.CoroutineDispatcher
 import kotlinx.coroutines.flow.first
 import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.launch
@@ -24,16 +25,19 @@ constructor(
   private val api: LobstersApi,
   private val savedPostsRepository: SavedPostsRepository,
   private val postDetailsRepository: PostDetailsRepository,
+  @IODispatcher private val ioDispatcher: CoroutineDispatcher,
 ) : ViewModel() {
   private var hottestPostsPagingSource: LobstersPagingSource? = null
   private var newestPostsPagingSource: LobstersPagingSource? = null
   private val hottestPostsPager =
     Pager(PagingConfig(20)) {
-      LobstersPagingSource(api::getHottestPosts).also { hottestPostsPagingSource = it }
+      LobstersPagingSource(api::getHottestPosts, ioDispatcher).also {
+        hottestPostsPagingSource = it
+      }
     }
   private val newestPostsPager =
     Pager(PagingConfig(20)) {
-      LobstersPagingSource(api::getNewestPosts).also { newestPostsPagingSource = it }
+      LobstersPagingSource(api::getNewestPosts, ioDispatcher).also { newestPostsPagingSource = it }
     }
 
   val hottestPosts
@@ -58,7 +62,7 @@ constructor(
   }
 
   fun toggleSave(post: SavedPost) {
-    viewModelScope.launch(Dispatchers.IO) {
+    viewModelScope.launch(ioDispatcher) {
       val saved = isPostSaved(post)
       if (saved) {
         savedPostsRepository.removePost(post)
@@ -69,14 +73,13 @@ constructor(
   }
 
   suspend fun getPostComments(postId: String) =
-    withContext(Dispatchers.IO) {
+    withContext(ioDispatcher) {
       val details = api.getPostDetails(postId)
       val extendedDetails = postDetailsRepository.getExtendedDetails(details)
       extendedDetails
     }
 
-  suspend fun getUserProfile(username: String) =
+  suspend fun getUserProfile(username: String) = withContext(ioDispatcher) { api.getUser(username) }
-    withContext(Dispatchers.IO) { api.getUser(username) }
 
   fun refreshHottestPosts() {
     hottestPostsPagingSource?.invalidate()

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

@@ -2,29 +2,31 @@ package dev.msfjarvis.claw.android.viewmodel
 
 import app.cash.sqldelight.coroutines.asFlow
 import app.cash.sqldelight.coroutines.mapToList
+import dev.msfjarvis.claw.android.injection.DatabaseDispatcher
 import dev.msfjarvis.claw.database.LobstersDatabase
 import dev.msfjarvis.claw.database.local.SavedPost
 import io.github.aakira.napier.Napier
 import javax.inject.Inject
-import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.CoroutineDispatcher
 import kotlinx.coroutines.withContext
 
 class SavedPostsRepository
 @Inject
 constructor(
   database: LobstersDatabase,
+  @DatabaseDispatcher private val dbDispatcher: CoroutineDispatcher,
 ) {
   private val savedPostQueries = database.savedPostQueries
-  val savedPosts = savedPostQueries.selectAllPosts().asFlow().mapToList()
+  val savedPosts = savedPostQueries.selectAllPosts().asFlow().mapToList(dbDispatcher)
 
   suspend fun savePost(post: SavedPost) {
     Napier.d(tag = TAG) { "Saving post: ${post.shortId}" }
-    withContext(Dispatchers.IO) { savedPostQueries.insertOrReplacePost(post) }
+    withContext(dbDispatcher) { savedPostQueries.insertOrReplacePost(post) }
   }
 
   suspend fun removePost(post: SavedPost) {
     Napier.d(tag = TAG) { "Removing post: ${post.shortId}" }
-    withContext(Dispatchers.IO) { savedPostQueries.deletePost(post.shortId) }
+    withContext(dbDispatcher) { savedPostQueries.deletePost(post.shortId) }
   }
 
   private companion object {