[BugFix] Fix issue of e-mail reminder being sent event after correspo…

…nding reminder occurrence is acknowledged.

link - personio/backend-coding-challenge#2

src/main/kotlin/com/personio/reminders/api/http/v1/requests/CreateReminderRequest.kt

@@ -2,8 +2,10 @@ package com.personio.reminders.api.http.v1.requests
 
 import com.fasterxml.jackson.annotation.JsonProperty
 import java.util.UUID
+import org.jetbrains.annotations.NotNull
 
 data class CreateReminderRequest(
+    @NotNull
     val text: String,
     @JsonProperty("employee_id")
     val employeeId: UUID,

src/main/kotlin/com/personio/reminders/usecases/occurrences/email/SendOccurrencesByEmailUseCase.kt

@@ -29,6 +29,7 @@ class SendOccurrencesByEmailUseCase(
     @Scheduled(cron = "0 */5 * * * *")
     fun sendReminders() = occurrences.findAt(Instant.now(clock))
         .filter { !it.isNotificationSent }
+        .filter { !it.isAcknowledged }
         .forEach { occurrence ->
             val message = Message(occurrence.reminder.text, occurrence.reminder.employeeId)
             mailer.send(message)

src/main/kotlin/com/personio/reminders/usecases/occurrences/find/FindOccurrencesUseCase.kt

@@ -20,3 +20,5 @@ class FindOccurrencesUseCase(
 ) {
     fun findAll(employeeId: UUID) = occurrencesRepository.findAt(Instant.now(clock), employeeId)
 }
+
+// Notification pattern

src/test/kotlin/com/personio/reminders/infra/postgres/occurrences/InMemoryOccurrencesRepository.kt

@@ -31,10 +31,7 @@ class InMemoryOccurrencesRepository(
     }
 
     override fun findAt(instant: Instant): Collection<Occurrence> {
-        return occurrences.filter {
-            !it.isAcknowledged &&
-                Instant.parse(it.date).isBefore(instant)
-        }
+        return occurrences.filter { Instant.parse(it.date).isBefore(instant) }
     }
 
     override fun findAt(instant: Instant, employeeId: UUID): Collection<Occurrence> {

src/test/kotlin/com/personio/reminders/infra/postgres/occurrences/OccurrencesRepositoryContractTest.kt

@@ -65,6 +65,29 @@ interface OccurrencesRepositoryContractTest {
         assertEquals(reminderForEmployee1.id, foundOccurrences.single().reminder.id)
     }
 
+    @Test
+    fun `find at should return all occurrences`() {
+        val reminderForEmployee1 = MotherObject.reminders().new()
+        val reminderForEmployee2 = MotherObject.reminders().new()
+        val occurrenceForEmployee1 = MotherObject.occurrences().newFrom(reminderForEmployee1)
+        val occurrenceForEmployee2 = MotherObject.occurrences().newFrom(reminderForEmployee2)
+        val repo = subjectWithData(
+            listOf(
+                reminderForEmployee1,
+                reminderForEmployee2
+            ),
+            listOf(
+                occurrenceForEmployee1,
+                occurrenceForEmployee2
+            ),
+            MotherObject.clock
+        )
+
+        val foundOccurrences = repo.findAt(Instant.now(MotherObject.clock))
+
+        assertEquals(0, foundOccurrences.size)
+    }
+
     @Test
     fun `should detect reminders to recur`() {
         val date = Instant.now(MotherObject.clock)

src/test/kotlin/com/personio/reminders/usecases/occurrences/email/SendOccurrencesByEmailUseCaseTest.kt

@@ -93,6 +93,27 @@ class SendOccurrencesByEmailUseCaseTest {
         verify(mailer, times(1)).send(any())
     }
 
+    @Test
+    fun `it should not send mail for already acknowledge occurrences`() {
+        val reminderTwo = MotherObject.reminders().new(text = "Remind me of creating tests")
+        val occurrenceTwo = MotherObject.occurrences().newFrom(reminderTwo, isAcknowledged = true)
+        val occurrences = InMemoryOccurrencesRepository(
+            mutableListOf(reminderTwo),
+            mutableListOf(occurrenceTwo),
+            MotherObject.clock
+        )
+        val mailer: MailerService = mock()
+        val subject = SendOccurrencesByEmailUseCase(
+            occurrences,
+            Clock.offset(MotherObject.clock, Duration.ofSeconds(1L)),
+            mailer
+        )
+
+        subject.sendReminders()
+
+        verify(mailer, times(0)).send(any())
+    }
+
     @Test
     fun `it should mark occurrence as already notified`() {
         val reminderOne = MotherObject.reminders().new()