chore: moved to flow.catch from try/catch in course outline and container viewmodels

Author: Ahsan Arif

course/src/main/java/org/openedx/course/presentation/container/CourseContainerViewModel.kt

@@ -170,25 +170,23 @@ class CourseContainerViewModel(
         _showProgress.value = true
 
         viewModelScope.launch {
-            try {
-                val courseStructureFlow = interactor.getCourseStructureFlow(courseId)
-                    .catch { e ->
-                        handleFetchError(e)
-                        emit(null)
-                    }
-                val courseDetailsFlow = interactor.getEnrollmentDetailsFlow(courseId)
-                    .catch { emit(null) }
-                courseStructureFlow.combine(courseDetailsFlow) { courseStructure, courseEnrollmentDetails ->
-                    courseStructure to courseEnrollmentDetails
-                }.collect { (courseStructure, courseEnrollmentDetails) ->
-                    when {
-                        courseEnrollmentDetails != null -> handleCourseEnrollment(courseEnrollmentDetails)
-                        courseStructure != null -> handleCourseStructureOnly(courseStructure)
-                        else -> _courseAccessStatus.value = CourseAccessError.UNKNOWN
-                    }
+            val courseStructureFlow = interactor.getCourseStructureFlow(courseId)
+                .catch { e ->
+                    handleFetchError(e)
+                    emit(null)
                 }
-            } catch (e: Exception) {
+            val courseDetailsFlow = interactor.getEnrollmentDetailsFlow(courseId)
+                .catch { emit(null) }
+            courseStructureFlow.combine(courseDetailsFlow) { courseStructure, courseEnrollmentDetails ->
+                courseStructure to courseEnrollmentDetails
+            }.catch { e ->
                 handleFetchError(e)
+            }.collect { (courseStructure, courseEnrollmentDetails) ->
+                when {
+                    courseEnrollmentDetails != null -> handleCourseEnrollment(courseEnrollmentDetails)
+                    courseStructure != null -> handleCourseStructureOnly(courseStructure)
+                    else -> _courseAccessStatus.value = CourseAccessError.UNKNOWN
+                }
             }
         }
     }

course/src/main/java/org/openedx/course/presentation/outline/CourseOutlineViewModel.kt

@@ -8,6 +8,7 @@ import kotlinx.coroutines.flow.SharedFlow
 import kotlinx.coroutines.flow.StateFlow
 import kotlinx.coroutines.flow.asSharedFlow
 import kotlinx.coroutines.flow.asStateFlow
+import kotlinx.coroutines.flow.catch
 import kotlinx.coroutines.flow.combine
 import kotlinx.coroutines.launch
 import org.openedx.core.BlockType
@@ -183,28 +184,27 @@ class CourseOutlineViewModel(
 
     private fun getCourseDataInternal() {
         viewModelScope.launch {
-            try {
-                val courseStructureFlow = interactor.getCourseStructureFlow(courseId, false)
-                val courseStatusFlow = interactor.getCourseStatusFlow(courseId)
-                val courseDatesFlow = interactor.getCourseDatesFlow(courseId)
-                combine(
-                    courseStructureFlow,
-                    courseStatusFlow,
-                    courseDatesFlow
-                ) { courseStructure, courseStatus, courseDatesResult ->
-                    Triple(courseStructure, courseStatus, courseDatesResult)
-                }.collect { (courseStructure, courseStatus, courseDates) ->
-                    if (courseStructure == null) return@collect
-                    val blocks = courseStructure.blockData
-                    val datesBannerInfo = courseDates.courseBanner
-
-                    checkIfCalendarOutOfDate(courseDates.datesSection.values.flatten())
-                    updateOutdatedOfflineXBlocks(courseStructure)
-
-                    initializeCourseData(blocks, courseStructure, courseStatus, datesBannerInfo)
-                }
-            } catch (e: Exception) {
+            val courseStructureFlow = interactor.getCourseStructureFlow(courseId, false)
+                .catch { emit(null) }
+            val courseStatusFlow = interactor.getCourseStatusFlow(courseId)
+            val courseDatesFlow = interactor.getCourseDatesFlow(courseId)
+            combine(
+                courseStructureFlow,
+                courseStatusFlow,
+                courseDatesFlow
+            ) { courseStructure, courseStatus, courseDatesResult ->
+                Triple(courseStructure, courseStatus, courseDatesResult)
+            }.catch { e ->
                 handleCourseDataError(e)
+            }.collect { (courseStructure, courseStatus, courseDates) ->
+                if (courseStructure == null) return@collect
+                val blocks = courseStructure.blockData
+                val datesBannerInfo = courseDates.courseBanner
+
+                checkIfCalendarOutOfDate(courseDates.datesSection.values.flatten())
+                updateOutdatedOfflineXBlocks(courseStructure)
+
+                initializeCourseData(blocks, courseStructure, courseStatus, datesBannerInfo)
             }
         }
     }

course/src/test/java/org/openedx/course/presentation/container/CourseContainerViewModelTest.kt

@@ -11,6 +11,7 @@ import io.mockk.verify
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.ExperimentalCoroutinesApi
 import kotlinx.coroutines.flow.emptyFlow
+import kotlinx.coroutines.flow.flow
 import kotlinx.coroutines.flow.flowOf
 import kotlinx.coroutines.test.StandardTestDispatcher
 import kotlinx.coroutines.test.advanceUntilIdle
@@ -236,10 +237,10 @@ class CourseContainerViewModelTest {
         every { networkConnection.isOnline() } returns true
         coEvery {
             interactor.getCourseStructureFlow(any(), any())
-        } returns flowOf(courseStructure)
+        } returns flowOf(null)
         coEvery {
             interactor.getEnrollmentDetailsFlow(any())
-        } throws Exception()
+        } returns flow { throw Exception() }
         every {
             analytics.logScreenEvent(
                 CourseAnalyticsEvent.DASHBOARD.eventName,

course/src/test/java/org/openedx/course/presentation/outline/CourseOutlineViewModelTest.kt

@@ -267,7 +267,7 @@ class CourseOutlineViewModelTest {
                     any()
                 )
             } returns Unit
-            coEvery { interactor.getCourseStatusFlow(any()) } throws UnknownHostException()
+            coEvery { interactor.getCourseStatusFlow(any()) } returns flow { throw UnknownHostException() }
 
             val viewModel = CourseOutlineViewModel(
                 "",
@@ -306,7 +306,7 @@ class CourseOutlineViewModelTest {
         coEvery { interactor.getCourseStructureFlow(any(), any()) } returns flowOf(courseStructure)
         every { networkConnection.isOnline() } returns true
         every { downloadDao.getAllDataFlow() } returns flow { emit(emptyList()) }
-        coEvery { interactor.getCourseStatusFlow(any()) } throws Exception()
+        coEvery { interactor.getCourseStatusFlow(any()) } returns flow { throw Exception() }
         val viewModel = CourseOutlineViewModel(
             "",
             "",