fix: remove CohortNotModifiedException (#24)

* fix: remove CohortNotModifiedException

* fix: lint issues

Author: vaibhav-jain-exp

core/build.gradle.kts

@@ -54,7 +54,7 @@ dependencies {
 // Publishing
 
 group = "com.amplitude"
-version = "0.10.0"
+version = "0.10.1"
 
 mavenPublishing {
     coordinates(

core/src/main/kotlin/cohort/CohortApi.kt

@@ -158,7 +158,7 @@ internal class CohortApiV1(
             }
         log.debug("streamCohort({}): status={}", cohortId, response.status)
         when (response.status) {
-            HttpStatusCode.NoContent -> throw CohortNotModifiedException(cohortId)
+            HttpStatusCode.NoContent -> return
             HttpStatusCode.PayloadTooLarge -> throw CohortTooLargeException(cohortId, maxCohortSize)
             else -> {
                 val input = response.bodyAsChannel().toInputStream()
@@ -205,7 +205,7 @@ internal class CohortApiV1(
                                     val lm = parsedLastModified
                                     if (id != null && lm != null) {
                                         if (lm <= existingLastModified) {
-                                            throw CohortNotModifiedException(id)
+                                            return
                                         }
                                     }
                                     ensureWriter()

core/src/test/kotlin/cohort/CohortApiTest.kt

@@ -271,4 +271,33 @@ class CohortApiTest {
             assertEquals(members.toSet(), stored?.members)
             assertEquals(members.size, stored?.size)
         }
+
+    @Test
+    fun `streaming cohort 204 no content is a no-op and does not throw`(): Unit =
+        runBlocking {
+            val cohortId = "stream-no-content"
+            val mockEngine =
+                MockEngine { _ ->
+                    respond(
+                        content = ByteReadChannel(""),
+                        status = HttpStatusCode.NoContent,
+                    )
+                }
+            val api = CohortApiV1(serverUrl, apiKey, secretKey, mockEngine)
+            val storage = com.amplitude.cohort.InMemoryCohortStorage()
+
+            // Seed existing cohort to ensure it remains unchanged
+            val existingDesc = com.amplitude.cohort.CohortDescription(cohortId, "User", 1, 100)
+            val writer = storage.createWriter(existingDesc)
+            writer.addMembers(listOf("1"))
+            writer.complete(1)
+
+            // Should not throw and should not change existing data
+            api.streamCohort(cohortId, 100, Int.MAX_VALUE, storage)
+
+            val stored = storage.getCohort(cohortId)
+            assertEquals(1, stored?.size)
+            assertEquals(100, stored?.lastModified)
+            assertEquals(setOf("1"), stored?.members)
+        }
 }